Tranny and Transfer Case Lube

[WarrenD]

I'm changing the fluids in my transmission and transfer case and was wondering what was a good lube to use?
Don't want to go synthetic, too much money. Local store has GL-5 (80-90) and GL-4 (85-90) in gallons.

 

[armytruck63]

Stay away from GL-5 in the tranny. I like the good old fashioned GL-1 straight 90 wt. You can usually find it at auto parts stores that sell a lot of tractor fluids etc. It's pretty cheap for a 5-gallon bucket. There are lots of discussions about this and I'm sure somebody will flame me for my opinion.

 

[Westech]

Why can't you use GL-5 in the trans? That is what we have in our M37. I have never seen a GL-5 not rated MT-1.
As long as it is gear lube your will be just fine.
80/90W works well.

 

[Floridianson]

I two perfer to stay away from any thing that has EP additives or sulfer in the mix. I do run Chevron Delo Trans lube ESI but it aint cheap. MT-1 rateing is for non syncro trans.

 

[Westech]

Its too not two....

 

[Floridianson]

I'm a blonde and it's before 12 oclock
Or maybe I have MPD and there is two of us in here!!!!!!!!!!

 

[Westech]

 

[WarrenD]

I didn't want to start a big hurrah like the deuce lube thread, I am curious to know what M37 owners are using in their trucks.

 

[rosco]

I use the multi-grade stuff, 75/90. because of the winter temps. Its good all year. Some consider the "EP" additives, not so good for the tranny, and they may have a point. It can cause them to kick out of gear with the helical cut gearing, so they use straight mineral oil. I don't want to have two different lubes, so just use the same in everything, differentials too. If your tranny/T-case is in reasonable condition, you will get by. But I would not recoment the straight gear lube today. Use the multigrade stuff. I never have used the synthetic stuff either, due to cost.

 

[GUNNY 155]

Did a lot of reaserch on this subject for my M37. Also read a lot of stuff from the vintage muscle car guys. The simple answer with out all the chemical engineering stuff is this. If it has all steel parts inside GL5 lubricants are fine. So transfer cases, front and rear axles are all good. If you are using the old style seals with leather stay away from the synthetic oils unless you like oil leaking on your floor. For transmissions that have non ferous metal parts (IE Syncro rings) you need lubricants with a GL4 rating otherwise expect early or rapid syncro failure. My 2 cents on this. And also based on a conversation with John Bizal from Midwest Military.

 

[WarrenD]

Thanks Gunny. I already settled on the GL4 stuff, 85-90. Also decided against synthetic. Nice to know I made the right choices!!

 

[majorhitt]

OK Now for my question on tranny fluid how do you get the silly stuff in there? I just about killed myself pumping it in with the pump that you draw it up with and then push it in the tranny. This stuff does not like to move without a few choice word helping it along. It was easier pushing the M37 up my drive way.

 

[GUNNY 155]

I have used the suction pump myself (no fun) but if you have one of the quart size bottles and have the room you can cut the tip off and squeeze it in pretty quick and easy. You can also put that tip on a smaller bottle if space is an issue. I am doing a frame up (or off) restoration so I have all the room in the world at this point. Funny thing about most MV's is for as big as they are a lot of things are not as easy to get at for service or repairs as one might think.

 

[WarrenD]

I used the black plastic pump I got at NAPA in the gallon jug of lube. It's not easy as the gears are right inside the opening. As I recall, I pushed the nozzle in at a downward angle and held it in place by holding the hose farther back against the frame. I also recall having to pump slowly, it took forever. Re: the pump, I quickly found out that a couple of tie wraps (plastic wire ties) or hose clamps were needed on both ends of the hose. First few pumps blew the hose off and shot lube everywhere.