JDToumanian
Active member
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- Phelan, CA
Hi Group,
I've been lurking for quite a while, and recently bought a 1968 Kaiser-Jeep M35A2. I bought one that had not run in a very long time, but I had no trouble getting it up and running (blown fuel pump fuse, clogged fuel filters, and air in the lines) and now it runs great. Blind, ignorant beginner's luck! The clutch is rather worn but everything else seems to be in good condition.
This is my first post. I've read all archived posts regarding GO gear lube and GAA grease, but I still was (am?) unsure of what to use... There's a lot of different opinions, and I want to use the best possible products on my truck.
Lubricant technology has changed a lot in recent years, and I believe that in some ways MIL-spec lubricants are a compromise due to the military's desire to use the same lubricant for many applications on a number of different vehicles (for example, using "GO" for transmissions, differentials, PTOs, transfer cases, steering gears and who knows what else on other vehicles). So I thought I would share my findings and invite opinions from other members.
GO (MIL-L-2105): I wanted to find a gear oil that met or exceeded the standards of MIL-L-2105. This part was easy... any GL-4, GL-5, or MT-1 oil of the appropriate weight meeting SAE J 2360 (formerly MIL-PRF-2105E) will exceed the requirements of MIL-L-2105. These new oils are better. I plan to use Chevron DELO ESI 85w-90 in the three differentials.
http://www.chevron.com/products/prodserv/nafl/trucking/content/prodspecs.shtm
You can click on "Data Sheets" to read the specs for DELO ESI Gear Lubricant.
But DELO ESI is not a good choice for manual synchrnized transmissions... It is too slippery... too good at what it does. A good choice for differentials but not good for synchros that NEED some friction to work properly. Also, as has been pointed out, some GL-5 oils can attack copper alloys... clearly not an oil for use with brass synchros or bronze bushings. What for transmissions then? I know a lot of members are using GL-1 from WalMart. I considered this, but it bothers me that it does not meet the MIL-spec, and the API says that "although occasionally still used, GL-1 is an obsolete" standard and should "only be used where the product specifically requires an oil conforming to GL-1" specifications. Although I think it would be fine, I could not find data showing that it met MIL-L-2105. GL-1 is old-time stuff! For the transmission, I think I've found something better, Redline Synthetic Manual Transmission Fluid MT 90, a 75w-90 GL-4 oil specifically formulated for manual transmissions with synchros.
http://www.redlineoil.com/products_gearlubricants.asp?pvID=74&prodID=57&subcatID=18
http://www.redlineoil.com/pdf/6.pdf
As for GAA grease, MIL-G-10924, that stuff isnt east to find. Spruce Mt. Surplus has 6.5 lb. cans, but the only other supplier was selling 35 lb. buckets. None of your average auto parts store greases, that I'm aware of, meet the spec. As pointed out in prior posts, this stuff is just old-fashioned long-fiber yellow grease. Surely there is something better? I wanted to use Mobil 1 Synthetic (red) grease, or Chevron DELO bearing grease (blue) but a member pointed out that there may be incompatibity with gear oils with these modern greases, and since there is a pretty good chance that axle seals will leak some oil into the wheel bearings (does anyone's Deuce axles NOT leak?!?)... I should use genuine surplus GAA for bearings but can safely use Mobil 1 grease for all the zerk fittings?
Sorry to make this long winded and to bring up oils and greases again, but I felt there is still a lot of confusion on this issue. I welcome all opinions.
Regards,
Jon
I've been lurking for quite a while, and recently bought a 1968 Kaiser-Jeep M35A2. I bought one that had not run in a very long time, but I had no trouble getting it up and running (blown fuel pump fuse, clogged fuel filters, and air in the lines) and now it runs great. Blind, ignorant beginner's luck! The clutch is rather worn but everything else seems to be in good condition.
This is my first post. I've read all archived posts regarding GO gear lube and GAA grease, but I still was (am?) unsure of what to use... There's a lot of different opinions, and I want to use the best possible products on my truck.
Lubricant technology has changed a lot in recent years, and I believe that in some ways MIL-spec lubricants are a compromise due to the military's desire to use the same lubricant for many applications on a number of different vehicles (for example, using "GO" for transmissions, differentials, PTOs, transfer cases, steering gears and who knows what else on other vehicles). So I thought I would share my findings and invite opinions from other members.
GO (MIL-L-2105): I wanted to find a gear oil that met or exceeded the standards of MIL-L-2105. This part was easy... any GL-4, GL-5, or MT-1 oil of the appropriate weight meeting SAE J 2360 (formerly MIL-PRF-2105E) will exceed the requirements of MIL-L-2105. These new oils are better. I plan to use Chevron DELO ESI 85w-90 in the three differentials.
http://www.chevron.com/products/prodserv/nafl/trucking/content/prodspecs.shtm
You can click on "Data Sheets" to read the specs for DELO ESI Gear Lubricant.
But DELO ESI is not a good choice for manual synchrnized transmissions... It is too slippery... too good at what it does. A good choice for differentials but not good for synchros that NEED some friction to work properly. Also, as has been pointed out, some GL-5 oils can attack copper alloys... clearly not an oil for use with brass synchros or bronze bushings. What for transmissions then? I know a lot of members are using GL-1 from WalMart. I considered this, but it bothers me that it does not meet the MIL-spec, and the API says that "although occasionally still used, GL-1 is an obsolete" standard and should "only be used where the product specifically requires an oil conforming to GL-1" specifications. Although I think it would be fine, I could not find data showing that it met MIL-L-2105. GL-1 is old-time stuff! For the transmission, I think I've found something better, Redline Synthetic Manual Transmission Fluid MT 90, a 75w-90 GL-4 oil specifically formulated for manual transmissions with synchros.
http://www.redlineoil.com/products_gearlubricants.asp?pvID=74&prodID=57&subcatID=18
http://www.redlineoil.com/pdf/6.pdf
As for GAA grease, MIL-G-10924, that stuff isnt east to find. Spruce Mt. Surplus has 6.5 lb. cans, but the only other supplier was selling 35 lb. buckets. None of your average auto parts store greases, that I'm aware of, meet the spec. As pointed out in prior posts, this stuff is just old-fashioned long-fiber yellow grease. Surely there is something better? I wanted to use Mobil 1 Synthetic (red) grease, or Chevron DELO bearing grease (blue) but a member pointed out that there may be incompatibity with gear oils with these modern greases, and since there is a pretty good chance that axle seals will leak some oil into the wheel bearings (does anyone's Deuce axles NOT leak?!?)... I should use genuine surplus GAA for bearings but can safely use Mobil 1 grease for all the zerk fittings?
Sorry to make this long winded and to bring up oils and greases again, but I felt there is still a lot of confusion on this issue. I welcome all opinions.
Regards,
Jon
