Should I use oe10 oil, ATF or Hydraulic?

[Dirty Deuce]

Hi Everyone,
I Just bought a 1952 M135 and wanted to change the Transmission Fluid. I have been told about 3 different fluids to use, OE 10 oil, ATF or Hydraulic Fluid. It seems to have oil or Hydraulic fluid in it now. Whats the diffenence between OE10 and Hydraulic fluid? Sorry if this seems to be a stupid question, I just want to do the right thing.

Thanks
DD

 

[Dan6wd]

When I got my first m211, there was engine oil inside of it. I switched over to dexron 3 automatic transmission fluid and never looked back! The oe10 oil is a straight weight oil, with no detergents in it. It is essentially straight crude oil right out of the ground. I recommend the dexron 3 atf, as I forementioned.

 

[NDT]

Welcome to the site. OE 10 is "Oil Engine" 10 weight oil. Hydraulic fluid is 10 weight oil with additives suitable for hydraulic systems. ATF is 10 weight oil with additives suitable for automatic transmissions. I have run Dextron in my M135 since 1983 with no ill effects, that would be my choice. Back in the 1950's, ATF had not yet been invented, so the military called for what was available, 10 weight engine oil.

Good luck with the truck, they are lots of fun and fast too.

 

[Dan6wd]

I forgot to mention, if you have not changed your transmission filter and gasket, do that as well. Your transmission will thank you for it. When I had mine, I also added some heat reducer additive along with the atf. The reverse gear is the weak link in these trucks. What people don't understand is that it was extremem heat caused by driver error that killed the tranny. the troops would load the heck out of the truck and use high range, when he needed to actually use low range, but the troops didnt care. they wanted to be able to go fast with a heavy load. this was told to me by a ww2 iwo jima, and korea veteran, who drove, owns, and rebuilds his own m211 and has rebuilt his own transmission before. Memphis equipment recommends dexron atf 3, thats what comes in their trucks, if you were to buy a truck from them. Get you a clean filter, some dexron atf 3 and a good quality transmission heat reducing agent. Also, if you ever pull anything in reverse, always use low range reverse gear!

 

[papabear]

I've heard that same thing Dan6wd...about the ATF-3 and the reverse gear as well.
Heck unless you're in combat trying to get away from something..what difference does it make how fast ya backup? Use low range for sure for our purposes.
Never thought about the heat reducer..but will when we service "Ole Betsy" the M211 again.

 

[Dan6wd]

I did it again! I forgot something. I must be suffering from CRS When you change the transmission fluid, crawl under the truck and gain lower access to the torque converter. Have someone spin the engine over a few times if necessary, until you see a drain plug at the bottom of the torque converter. Drain the torque converter as well! When you refill, if you did it right the transmission and torque converter refill capacity is 16 quarts. You must check the transmission fluid, with the gear selector in the drive position. so chock your wheels and set the parking brake. It's not fun when when when 13,000 pounds worth of truck takes off, with no driver, and you have to chase her down! One final thing. The transmission has an internal cooler built inside of it. It utilizes coolant from the radiator to circulate into the tranny cooler, which as I said, is inside the tranny. Perform a good coolant flush, to not only flush your radiator, but your tranny cooler as well. Whew!, ok, I'm really done this time!

 

[Dirty Deuce]

Thanks so much for the info! I'll take your advise and try the ATF 3

 

[Dan6wd]

.....and the heat reducer you can get it at any parts store, or, jeg;s, or summit racing, or my toolbox!, or some used already thats in my tranny now -lol

 

[BugEyeBear]

GREAT ADVISE GUYS!!

I recently acquired a nice '52 XM211 in good running condition & I have similar desires to get fresh fluids in everything (as I never trust the judgement of prior owners, especially when it comes to fluids...).

I've heard SO MANY Warnings about these auto transmissions being weak, but I've always suspected that most of it was due to either poor maintenance or abuse. It is good to hear others expressing the same opinion.

& I have to think that the detergents in ATF would help to keep everything clean & gum free. That'll probably be MY choice!


(BTW: This thread should probably be referenced over in the "Early Deuce" forum...)

"Cheers!"
-Bear-

 

[badgmc56]

On the front part of the tranny pan you will see a oval cover. Drain the coolant and remove the cover. The tranny cooler is under the cover. Check to see if there is crud and grime built up under the cooler. If there is and you don't clean it out, no matter what kind of fluid or heat reducer you use it won't matter. Your tranny will be toast from lack of being able to cool down because of the blockage.