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Aeroshell 5 out of production?

jcarne

Well Known Member
Patron
Soooo... anyone know if this stuff is out of production? Spruce has an indefinitely back order and I can't find it in stock just about anywhere. Would really like to lube my Hartzell with it and not #6.
 
Soooo... anyone know if this stuff is out of production? Spruce has an indefinitely back order and I can't find it in stock just about anywhere. Would really like to lube my Hartzell with it and not #6.

I dropped an email to Hartzell asking for advice last week, but probably won't hear from them for a few days. There must be some grease that is compatible.
 
I wont use Aeroshell 5 in my mower let alone an airplane. I have dried up old stock tubes tubes that I've thrown in the trash. Greasing Hartzells ever year causes more problems than it prevents. Pushing fresh grease in increases the likelihood of separated oil getting past the teflons and big orings. Radial movement is less than 1/8" at the bearing balls so its impossible for fresh grease to make its way to the interface between the bearing balls and the races.
 
I wont use Aeroshell 5 in my mower let alone an airplane. I have dried up old stock tubes tubes that I've thrown in the trash. Greasing Hartzells ever year causes more problems than it prevents. Pushing fresh grease in increases the likelihood of separated oil getting past the teflons and big orings. Radial movement is less than 1/8" at the bearing balls so its impossible for fresh grease to make its way to the interface between the bearing balls and the races.

Bob, do you have a recommendation? Thanks.
 
Bob, do you have a recommendation? Thanks.

Yes, dont grease. Its pointless. There's no way to force old grease out without complete disassembly. There is so little movement that none of it really matters. I would be willing to bet a Hartzell would work just fine with zero grease.
 
There's no way to force old grease out without complete disassembly.

Sort of -- when the mineral oil separates from the paraffin, it has a nasty tendency of seeping past the blade root seals and into the slip stream; ending up on the windscreen, airframe...(sigh) the chunky paraffin is left behind.

Disgusting "pimple popper" pictures attached for reference.

edit: this is Aeroshell 6 after only 6 months of disuse. (airplane was down for paint...)
 

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I wont use Aeroshell 5 in my mower let alone an airplane. I have dried up old stock tubes tubes that I've thrown in the trash. Greasing Hartzells ever year causes more problems than it prevents. Pushing fresh grease in increases the likelihood of separated oil getting past the teflons and big orings. Radial movement is less than 1/8" at the bearing balls so its impossible for fresh grease to make its way to the interface between the bearing balls and the races.

Sir,
With all due respect, this is very bad advice. Mowers? I have a few of questions:
How did you come to this conclusion that lubrication of a Harztell is not a good Idea?
Do you realize that is against the published recommendations of Hartzell the manufacturer of the propeller?
Have you read the owners manual?
Regards,
Joe
 
Soooo... anyone know if this stuff is out of production? Spruce has an indefinitely back order and I can't find it in stock just about anywhere. Would really like to lube my Hartzell with it and not #6.

It is out of production right now. The plant literally blew up. They almost had a Force Majeure.
https://www.manufacturing.net/safet...prompts-evacuations-in-northern-illinois-town

>>MODERATOR EDIT: 3rd party non-VAF-advertiser link removed per VAF posting rules.<<

I took that pic on my way to RFD that day to go work on my plane. It burned for days and there was a TFR over the fire as well. Nasty, big fire:
 

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Sort of -- when the mineral oil separates from the paraffin, it has a nasty tendency of seeping past the blade root seals and into the slip stream; ending up on the windscreen, airframe...(sigh) the chunky paraffin is left behind.

Disgusting "pimple popper" pictures attached for reference.

edit: this is Aeroshell 6 after only 6 months of disuse. (airplane was down for paint...)

You pump grease into one side and the grease should come out the other side of the hub, or until you have inserted 1 oz of grease. Count the pumps into a shot glass if you are unsure what 1 oz looks like. The most important thing I can tell you is that you need to poke the hole where the grease is to emerge with a piece of safety wire or a paper clip or something similar. The wax in the grease will make a temporary plug, so poke before you grease. You add 1 oz or until it emerges out the other side. That is all it gets until next year or 400 Hours, which ever is 1st.
My comments start of post #19 of this thread.
https://vansairforce.net/community/showthread.php?t=201837&page=2
Direction is given in Hartzell owners manual 115N
https://hartzellprop.com/MANUALS/115N-0000-A.pdf

Here is a Hartzell Video:
Lubrication starts about 19:00:
https://www.youtube.com/watch?v=LHSWwJzWgRU

Please call Hartzell or contact myself with any questions pertaining to greasing your prop.
 
Care to elaborate Dan?

The mineral oil seeps out of it rather quickly. So, load a new tube in the gun, grease the prop, place it on the shelf. Come back in a few months to find an oil puddle, and solids the gun won't pump. Didn't take many annuals to get tired of that nonsense.

I've had better results with #6...and grease my tractors with it ;)
 
The mineral oil seeps out of it rather quickly. So, load a new tube in the gun, grease the prop, place it on the shelf. Come back in a few months to find an oil puddle, and solids the gun won't pump. Didn't take many annuals to get tired of that nonsense.
it ;)

+1. The shelf life is ridiculously small. I always wonder what the condition is of the grease in the prop.
 
Sir,
With all due respect, this is very bad advice. Mowers? I have a few of questions:
How did you come to this conclusion that lubrication of a Harztell is not a good Idea?
Do you realize that is against the published recommendations of Hartzell the manufacturer of the propeller?
Have you read the owners manual?
Regards,
Joe

Correct. I would not use Aeroshell #5 on my mower let alone a certified aircraft. It is an old clay grease formulation that does not perform well.

I have a copy of the service manual that is only available to authorized shops and have torn down many of these props and put them back together for experimentals or disassembled them for transport. I also have a source for parts that are only available to authorized prop shops. I also can read. The last propeller I disassembled was November 2021.

I do many owner-assist annuals and condition inspections. I have on several occasions observed Hartzells start spitting grease after servicing them. The path of grease between the zerks WILL NOT flush all grease out. Packing the cavity where the grease resides simply can force separated oil past the teflons and blade oring.
 
It is out of production right now. The plant literally blew up. They almost had a Force Majeure.
https://www.manufacturing.net/safet...prompts-evacuations-in-northern-illinois-town

******SNIP*****

I took that pic on my way to RFD that day to go work on my plane. It burned for days and there was a TFR over the fire as well. Nasty, big fire:

Thanks for the reply Joe, that explains it!

The mineral oil seeps out of it rather quickly. So, load a new tube in the gun, grease the prop, place it on the shelf. Come back in a few months to find an oil puddle, and solids the gun won't pump. Didn't take many annuals to get tired of that nonsense.

I've had better results with #6...and grease my tractors with it ;)

Interesting, are you sure that's not backwards? I had heard others say it was the other way around as far as oil separation. In any sense, a few people have mentioned that #6 had a formula change (possibly what prompted Hartzell to change?) so I'm a little nervous about using the 6. Two guys specifically reached out to me via PM a few months back to ask if my prop was pissing oil all over the wind screen like theirs was. One even went so far as to get Hartzell to warranty it and reseal with the new stuff. My prop was however manufactured by Hartzell before the formula change.

https://vansairforce.net/community/showthread.php?t=178968
 
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The mineral oil seeps out of it rather quickly. So, load a new tube in the gun, grease the prop, place it on the shelf. Come back in a few months to find an oil puddle, and solids the gun won't pump. Didn't take many annuals to get tired of that nonsense.

I've had better results with #6...and grease my tractors with it ;)

All grease will separate under the force of a normal lever and Pistol type grease gun. Its the spring. Try and Pull the handle on the grease gun back so the spring is not continually pushing on the grease. When you need grease release the spring, purge of air, grease the prop per Hartzell 115N and pull the spring back until you need it again. Its about all you can do, unless you remove the tube of grease.
 
All grease will separate under the force of a normal lever and Pistol type grease gun. Its the spring.

I've had numerous unused tubes of Aeroshell dry out and leak oil on the shelf.

A car can go 200K miles typically on a set of wheel bearings never requiring maintenance with a tiny amount of grease. Why does something that only moves 1/8" with 1/2" bearing balls require regreasing every annual?
 
Why does something that only moves 1/8" with 1/2" bearing balls require regreasing every annual?

Centrifical force. A propeller is in essence a centrafuge. For the same reason a propeller gets sludge in it from the fuel, that ends up in the oil. That same oil is used to change pitch, in the propeller, that gets centruged out in the form of sludge in the prop.
Pic for ya'
 

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Correct. I would not use Aeroshell #5 on my mower let alone a certified aircraft. It is an old clay grease formulation that does not perform well.

I have a copy of the service manual that is only available to authorized shops and have torn down many of these props and put them back together for experimentals or disassembled them for transport. I also have a source for parts that are only available to authorized prop shops. I also can read. The last propeller I disassembled was November 2021.

I do many owner-assist annuals and condition inspections. I have on several occasions observed Hartzells start spitting grease after servicing them. The path of grease between the zerks WILL NOT flush all grease out. Packing the cavity where the grease resides simply can force separated oil past the teflons and blade oring.

Do you have your pirated tech data in an electronic format? Try "Ctrl" "F" and tell me any where it tells you to "flush" out grease of a blade retention bearing in a Hartzell compact propeller. There is a specific procedure set forth by Hartzell. I think you are wrong for even posting such rubbish to "flush" grease. Here is what happens when to try to "flush". You fill the hub up with grease. Then the prop leaks and you blame the design and the tech data? I tried to search "Purge" on your behalf and I posted what Hartzell says about that as well.
Have a nice evening.
 

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Do you have your pirated tech data in an electronic format? Try "Ctrl" "F" and tell me any where it tells you to "flush" out grease of a blade retention bearing in a Hartzell compact propeller. There is a specific procedure set forth by Hartzell. I think you are wrong for even posting such rubbish to "flush" grease. Here is what happens when to try to "flush". You fill the hub up with grease. Then the prop leaks and you blame the design and the tech data? I tried to search "Purge" on your behalf and I posted what Hartzell says about that as well.
Have a nice evening.

I have a paper manual in an original 3-ring Hartzell binder that I purchased from Hartzell. Its a little strange for someone to accuse someone of using "pirated" tech data, not knowing anything about what data I have or my background.

Perhaps you should reread my statements which I said which agrees 100% with the manual about not being able to purge old grease thru the zerks. I really dont think you understood anything I said.
 
+1. The shelf life is ridiculously small. I always wonder what the condition is of the grease in the prop.

I wonder if this is a contributing reason why Hartzell discontinued use of Aeroshell and switched to gynco? I had a heck of a time finding gynco when the switch first came out ($50/tube), but it seems available now.
 
I have a paper manual in an original 3-ring Hartzell binder that I purchased from Hartzell. Its a little strange for someone to accuse someone of using "pirated" tech data, not knowing anything about what data I have or my background.

Perhaps you should reread my statements which I said which agrees 100% with the manual about not being able to purge old grease thru the zerks. I really dont think you understood anything I said.

I really do not care, other than you are giving out miss information about greasing, or telling people they should not grease Hartzell propellers. Pitch the three binder and look on the web. Hartzell puts it out there for a reason.

This is the 3rd time I've cut and pasted this whole thing in the last week.
I see people get this one wrong and fill the hub with grease, often, way to often.
Proper way to lubricate a Hartzell "Compact" propeller.
See Hartzell Owners manual 115N, click on the link below and go to page 6-7. All the instruction for prop lubrication, of a Hartzell "Compact" propeller, you need is there on the web for your enjoyment. Please take a look before you start the lubrication of your prop. You can always contact Hartzell. Or feel free to call, email, PM me if you need help in understanding something.
Hartzell 115N link:
https://hartzellprop.com/MANUALS/115N-0000-A.pdf

Here is a really old Hartzell video about props. Lubrication starts at about the 19:00 mark:
https://www.youtube.com/watch?v=LHSWwJzWgRU
I'm gonna go off the deep end a little here and explain.
A propeller is a giant centrifuge that tends to separate grease back into the stuff it is made from. Mainly a waxy type thickener (Usually clay or Lithium) and oil. I like the old Aeroshell #5 that we used for decades in props. It worked well. I do not like #6 that has been the factory prop fill for a while. Over the years I have seen many props with Aeroshell #6 in them that have the grease separate during operation. The blade seals are designed to hold grease, not oil. Then typically the oil from the grease tends to leave the prop (through the blade seals) and leave the waxy thickener behind. So the thickener is not a good lubricant by itself and with little or no oil in the mix tends to make for corroded blade retention bearings ($$$). This is just my personal observation over the years. Hartzell now uses a factory fill with Nyco GN3058 grease, which in theory will be even better than the #6 and hopefully even #5. I'm sure Hartzell has tested this new Nyco grease. I like that they are willing to go to a potentially better grease. Jury is still out on the Nyco as I've not seen a prop come apart yet with the Nyco grease. I do like that the Nyco is an anti corrosion grease we have used on other static propeller applications as an anti corrosive grease at our shop with great success. The USN has even gone to great lengths to come up with a spec. for corrosion inhibiting grease (MIL-PRF- 81322 ) which GN3058 now meets.
When pumping in the grease, poke out the wax thickener that has most likely plugged the opposite zerk. That is the hole that you have removed either the zerk or plug as the case may be. Use a piece of safety wire or something similar.
Insert/apply grease to each Zerk until grease comes out the other side, or until you have pumped approximately 1oz of grease (Approx 6 pumps/strokes on most lever grease guns). If you are unsure of how much 1 oz of grease is, or looks like, pump some out into a shot glass and count the strokes needed for 1oz for your particular grease gun.
Aeroshell #5 and #6 can be intermixed, per Hartzell. You are supposed to placard the aircraft restricting operation below -40°F if there is any Aeroshell #5 in the prop. I have to be honest, I've never seen that placard on any aircraft and there are thousands of Harztell props that have been lubricated with Aeroshell #5 over the decades.

The idea of pumping till the grease runs clear can lead to problems on the new hubs with the grease fittings Zerks located along the parting line of the hub. That hole is threaded 1/4 x 28 and there is a stepped feature inside of the hub that the diameter is much smaller than the threaded area you can see from the outside. On the new hubs, they did that for added strength in the area of the blade retention bearing. Because of the small diameter of that hole you may mistakenly pump the hub full of grease un-intentionally in the quest for clean grease to come out of the other side of the hub.
The older hubs had the zerk/fitting right on the bearing in the thinnest part (not good for strength btw) of the hub had that 1/4 x 28 thread all the way through, inside and out. If you don't know or are un-shure of which hub you are dealing with, please follow the instructions given in Hartzell owners manual 115N. You generally can't go wrong with FAA approved tech data.
As someone who has greased several hundreds (possibly even more) of propellers, I think the biggest problem is that people do not realize the hole on the other side, where the grease is supposed to emerge from, is plugged with that waxy build-up of the greases' thickener in that little bore. People just keep a pumping and a pumping, and a pumping, till the center of the hub is filled with grease. Then the prop can become sluggish and at that point it needs to come apart. While filling the prop with the correct grease, once grease starts coming out the other side of the hub, the retention bearing is full of grease. Stop, blade retention bearing is full of grease, you are done. Not that the hub is full of grease, rather, that blade retention bearing is full of grease. If you have to keep pumping more than 1oz you are potentially filling the inside of the hub with grease.

The object/goal is to grease the blade shank retention bearings (1/2" diameter balls and races). The key is not fill the center of the hub with grease, by over-servicing.

Glad I didn't have to type that out again. Feel free to share with whoever will listen.


Let me know if you'd like to hear my background in propellers.
Have a nice day!
 
I wonder if this is a contributing reason why Hartzell discontinued use of Aeroshell and switched to gynco? I had a heck of a time finding gynco when the switch first came out ($50/tube), but it seems available now.
They were force to change the formulation of many products due to European REACH regulations in 2018. That is why they are not selling many Aeroshell products in Europe.
https://echa.europa.eu/regulations/reach/understanding-reach
Even regulating grease!!!
https://www.wca-environment.com/app...-01_SETAC_Poster_ERGTC-wca_Matrix_effects.pdf

It effects everything, Grease, paint, epoxy, adhesives...
Guess where the replacement Grease/products are made???
Why Europe, of course!
Its really effecting me at work now. There are single source suppliers with certain requirements listed manuals that really has had us scrambling for products that meet specs, then throw in raw material shortages = Perfect storm of shortages.
Then there is this little issue about grease:
https://www.wifr.com/2021/07/21/chemtool-fire-causes-potential-grease-shortage/
 
Bob, do you have a recommendation? Thanks.

Yes, dont grease. Its pointless. There's no way to force old grease out without complete disassembly. There is so little movement that none of it really matters. I would be willing to bet a Hartzell would work just fine with zero grease.

I'm not so sure that suggesting folks NOT follow the advice of Hartzell is a prudent or responsible one. I'm pretty confident that the folks at Hartzell have a bit more experience in the service history of their products than anyone here on VAF.

In order to avoid 'over greasing' (grease being pushed out past the seals) my suggestion is that both the grease and prop should be warm before adding a few pumps, and do it very slowly, by hand grease gun only and make sure the opposite port if free and clear. I also change the grease every year in my gun so I am always using 'fresh' material.
 
I'm not so sure that suggesting folks NOT follow the advice of Hartzell is a prudent or responsible one. I'm pretty confident that the folks at Hartzell have a bit more experience in the service history of their products than anyone here on VAF.

It is my opinion, based on my own experience, that these things are way over maintained which causes more problems than it solves despite the manufacturers recommendations. There is no regulatory requirement to follow the manufacturers instructions. If you guys don't agree with my assessment thats fine I certainly wont lose any sleep over it. Since the OP can't get the grease anyway I am suggesting that skipping greasing will not cause an airworthiness issue.
 
No idea of how this particular AC was maintained. Cracked blade retention bearing (A-2022, about $450 each btw).
 

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No idea of how this particular AC was maintained. Cracked blade retention bearing (A-2022, about $450 each btw).

Joe, am I seeing the crack where marked?

The blue coloration on the other race is interesting. Is that temperature related?

BTW, thanks for the posts. Keep 'em coming!
.
 

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Joe, am I seeing the crack where marked?

The blue coloration on the other race is interesting. Is that temperature related?

BTW, thanks for the posts. Keep 'em coming!
.

Its cracked at the "break" or split. The area is circled with a black sharpie.
I'll re-magnetize it and get a picture of it in the black light in the NDT area. This is why we perform overhauls on props. This is basic Magnetic Partcle Inspection (MPI). Our level III may already have a picture. We will ask the customer if we can use this part for training as a part with a "known defect".
Blue area is just staining. Common of both the race and balls to get stained like that. The inside of the prop doesn't get hot, if that is what you are asking?. Its very hard steel and that stain will easily clean off with a maroon scotch-brite pad.

Maybe I should start a new thread? I have probably several hundred pics on my phone of various propeller defects. Not all Hartzell. Lots of airliner and military stuff. Many of the pictures in this FAA AC were taken at our shop, or pics we had on file.
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_20-37e.pdf
I remember walking the FAA guys through the shop while they were snapping pics. One of the FAA guys is now in charge of the Greater Chicago ACO.
 
Nyco GN3058 grease

I just got my prop back from an overhaul from a Hartzell repair center and I noticed the new grease label on the hub.

It says to use Nyco GN3058.

Joe knows what he is talking about. And he references the correct page in the book. Hartzell Owners manual 115N.
 
Blue area is just staining. Common of both the race and balls to get stained like that. The inside of the prop doesn't get hot, if that is what you are asking?.

Yep, that's what I was asking. The blue looks a lot like heat coloration, and I was really surprised to see it. Glad to hear different!

Maybe I should start a new thread? I have probably several hundred pics on my phone of various propeller defects.

Oh yes, please, please, please...
 
The grease recommendations keep changing over the years, but I certainly wouldn't stop greasing them. We send out about 2-3 Hartzell C/S props every 2 month, and about half of them come back with condemned race bearings.

Vic
 
The grease recommendations keep changing over the years, but I certainly wouldn't stop greasing them. We send out about 2-3 Hartzell C/S props every 2 month, and about half of them come back with condemned race bearings.

Vic

So. You grease them and they leak, then they have to go out to get resealed. Then half of them come back having bad races (usually brinnelling) so the grease doesn't help that either. None of this makes any sense.
 
Shell #5 and #6 can be used interchangeably; However Hartzell has a SB prohibiting the use of #22 unless it is a newer hub that came from the factory with #22; otherwise, if the hub is totally cleaned of #5 or #5, then #22 can be used. The older are mineral based, the newer is synthetic. 'll go with the manufactures recommendations.

DAR Gary
 
Looking like this may be difficult to do now that Aeroshell is out of production due to the fire.

Which was the original issue...so a) is there any news on when production will resume, and b) since the manual says NOT to mix greases without disassembly, what do we do in the meantime?
 
ok, this is important!!!!
I spent most of the day doing research on propeller lubricants. HARTZELL and other suppliers cannot get Aeroshell #5 and #6, the only lubricants they authorize in most of their hubs, unless:1. The prop came from the factory with Aeroshell 22; or 2. The prop has been totally cleaned of aeroshell 5 or 6, and then aeroshell 22 can be used. Due to the fire at the plant where these lubricants were manufactured, they are out of stock everywhere!
So, I found that #5 is MIL SPEC G 23139; #6 IS MIL SPEC G 3545 SUPERCEEDED BY MILSPEC G 81322.
Cross reference for these Mil Specs is as follows:
Aeroshell #5 = Royco #45; GN 05; and Total Airgrease #5.
Aeroshell #6 = Nyco GN15; and Total Airgrease 5.
I'm going to roll the dice and go with Royco #45, as I do not need the excessive cold temperature protections that #6 offers, nor has as much separation. I suggested to Hartzell that they publish something for the aviation consumer to reference. PS Do not over lube! 1 to 1.5 ounces is sufficient every year or 400 hours. The newer hubs will not necessarily show any grease at the plug port. Refer to Hartzell SB on the subject.
DAR Gary
 
ok, this is important!!!!
I spent most of the day doing research on propeller lubricants. HARTZELL and other suppliers cannot get Aeroshell #5 and #6, the only lubricants they authorize in most of their hubs, unless:1. The prop came from the factory with Aeroshell 22; or 2. The prop has been totally cleaned of aeroshell 5 or 6, and then aeroshell 22 can be used. Due to the fire at the plant where these lubricants were manufactured, they are out of stock everywhere!
So, I found that #5 is MIL SPEC G 23139; #6 IS MIL SPEC G 3545 SUPERCEEDED BY MILSPEC G 81322.
Cross reference for these Mil Specs is as follows:
Aeroshell #5 = Royco #45; GN 05; and Total Airgrease #5.
Aeroshell #6 = Nyco GN15; and Total Airgrease 5.
I'm going to roll the dice and go with Royco #45, as I do not need the excessive cold temperature protections that #6 offers, nor has as much separation. I suggested to Hartzell that they publish something for the aviation consumer to reference. PS Do not over lube! 1 to 1.5 ounces is sufficient every year or 400 hours. The newer hubs will not necessarily show any grease at the plug port. Refer to Hartzell SB on the subject.
DAR Gary
Edir: fixed error. Also, factory props for the last few years come with some synthetic Nyco grease which is not to be mixed with AeroShell 5 or 6.
 
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I think you have this backwards. #5 offers very cold wx protection. If you use #6 you must placard the prop, ‘not for use below -20(?? I forget the actual number, and if it’s C or F). Also, factory props for the last few years come with some synthetic Nyco grease which is not to be mixed with AeroShell 5 or 6.

Nope, cal pilot had it right. In 115N it wants a placard if #5 is used.
 
ok, this is important!!!!
I spent most of the day doing research on propeller lubricants. HARTZELL and other suppliers cannot get Aeroshell #5 and #6, the only lubricants they authorize in most of their hubs, unless:1. The prop came from the factory with Aeroshell 22; or 2. The prop has been totally cleaned of aeroshell 5 or 6, and then aeroshell 22 can be used. Due to the fire at the plant where these lubricants were manufactured, they are out of stock everywhere!
So, I found that #5 is MIL SPEC G 23139; #6 IS MIL SPEC G 3545 SUPERCEEDED BY MILSPEC G 81322.
Cross reference for these Mil Specs is as follows:
Aeroshell #5 = Royco #45; GN 05; and Total Airgrease #5.
Aeroshell #6 = Nyco GN15; and Total Airgrease 5.
I'm going to roll the dice and go with Royco #45, as I do not need the excessive cold temperature protections that #6 offers, nor has as much separation. I suggested to Hartzell that they publish something for the aviation consumer to reference. PS Do not over lube! 1 to 1.5 ounces is sufficient every year or 400 hours. The newer hubs will not necessarily show any grease at the plug port. Refer to Hartzell SB on the subject.
DAR Gary

So did they outright tell you that these greases could be used?
 
The service letter...

See this --
https://hartzellprop.com/SERVICE-DOCUMENTS/SL/HC-SL-61-366.pdf

Pay attention to the exception/warning note on page 4 of the service letter -- to wit, you can mix Aeroshell 6 and Aeroshell 5, however - you need to be mindful of cold weather operation as the useful cold temperature limit for Aeroshell 5 is higher (warmer) than Aeroshell 6.

As an aside Adding to the confusion, -40° is the convergence point for both temperature scales...

From the TDS for each:

Aeroshell 5: -23°C to 177°C
Aeroshell 6: -40°C to 121°C

Further --

There's no mention of Aeroshell 22 in the service letter from Hartzell. It's only mentioned as a replacement for Aeroshell 5 on the Shell Website.

A comparison of the TDS/MSDS for each should be in order to determine the mix-ability of Aeroshell 5, 6 and 22
 
ok, this is important!!!!
I spent most of the day doing research on propeller lubricants. HARTZELL and other suppliers cannot get Aeroshell #5 and #6, the only lubricants they authorize in most of their hubs, unless:1. The prop came from the factory with Aeroshell 22; or 2. The prop has been totally cleaned of aeroshell 5 or 6, and then aeroshell 22 can be used. Due to the fire at the plant where these lubricants were manufactured, they are out of stock everywhere!
So, I found that #5 is MIL SPEC G 23139; #6 IS MIL SPEC G 3545 SUPERCEEDED BY MILSPEC G 81322.
Cross reference for these Mil Specs is as follows:
Aeroshell #5 = Royco #45; GN 05; and Total Airgrease #5.
Aeroshell #6 = Nyco GN15; and Total Airgrease 5.
I'm going to roll the dice and go with Royco #45, as I do not need the excessive cold temperature protections that #6 offers, nor has as much separation. I suggested to Hartzell that they publish something for the aviation consumer to reference. PS Do not over lube! 1 to 1.5 ounces is sufficient every year or 400 hours. The newer hubs will not necessarily show any grease at the plug port. Refer to Hartzell SB on the subject.
DAR Gary

This is the only post that provides a potential solution unless and until AS5 and AS6 are available again.
 
#6 IS MIL SPEC G 3545 SUPERCEEDED BY MILSPEC G 81322.

Cross reference for these Mil Specs is as follows:
...
Aeroshell #6 = Nyco GN15; and Total Airgrease 5.

I found sites that indicate AS6 is MIL-PRF-24139.

Detailed Product Description

AeroShell Grease 6 is a general purpose airframe grease for use in antifriction bearings, gearboxes and plain bearings within the temperature range of –40C to +121C.

Specifications, Approvals & Recommendations

U.S. : Approved MIL-PRF-24139A, Meets MIL-G-7711A (Obsolete)
British: Approved DEF STAN 91-12
French: Equivalent DCSEA 382/A
NATO Code : G-382
Joint Service Designation : XG-271

I don't know yet which others are equivalent...

ETA this site:

https://emtc.aero/wp-content/uploads/2021/01/Mappe2.GREASE-XREF-1.pdf

which concurs with NYCO GN15 and Total Airgrease 15 (not #5...perhaps there was a typo?) being equivalent.
 
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There is some Aeroshell 5 available on evilbay. You will need to feed it into your grease gun. The only amount this person has available is a 6.6 lb can, no tubes. I had posted a link earlier but it was taken down. Last I looked they had "More than 10 available". I've never bought anything from the guy and I'm just posting as a potential source.
https://www.ebay.com/itm/154542037589?hash=item23fb6c5a55:g:I2wAAOSwRpNg-yIJ

Per Hartzell manual 115N you can intermix the #5 and #6 as it uses the same thickener. That being said you are supposed to placard the aircraft that flight below -40°F is prohibited if you pump #5 in the prop.
If your prop currently Nyco GN3058 in it, keep using that grease, as it is NOT compatible with any Aeroshell products. If you do not have the GN3058 in it, the prop will need to be completely dis-assembled for the new GN3058 to be used for prop lubrication.
I would not lubricate any propeller with #22. It is specified (by Hartzell) specifically in the high flying Piaggio 180 and Grobe aircraft. We tried #22 decades ago and it tended to separate quickly in a propeller, except those plaes flying up in the Flight Levels.
Perhaps Hartzell will follow up with something else to mix with #5 and #6??? I doubt it... Probably not gonna happen, as they have already gone to the new Nyco Grease, even before the big Fire at the grease plant in Rockton, IL.
Buy what you can, when you can, Otherwise, Plan on a reseal guys, Unless some miracle happens there will be no Aeroshell #5 or #6 available in the near future.
I'm even planning on not using #5 in the wheel bearing of the Cherokee next year. I have some #5 in the hangar, but will offer it to friends that are running #5 in their props.
One other tip. Pull the plunger to remove spring pressure on the actual grease in your grease gun. That constant spring force tends to force the oils out of the thickeners in the grease from one year to the next.
 
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