both back pumkin differential fluid??

[carbonraptor]

hi there. i know im a noob in this site so far but i have a very basic question that im hoping someone will help me with. what kind of differential oil does the back pumkpins take? just generit stuff? thanks in advance guys.

Ryan

 

[M813A1]

You got a nice looking truck. You need to download he TM.'s and read !! You can download the TM's here from the Resource tab above . An 85W90 oil should be what it takes in all the axles and transfer . Hope that helps

 

[jonesal]

Doghead gonna say it sooner or later. Even noobs have to look at the TM's, especially the Lube Order (LO). They are free for download if you back off a forum or two. That information is readily available there and will answer your questions.

Allen
TM Connoisseur
'55 M38A1
'70 M35A2 for sale
'84 M923

 

[Danl]

Danl M915A1

The tm will help, but thay take time to figur out and is real boring, but look them over, dog head loves them. but never feal shy of asking for info if i catch it and can help out I will I've been working with 5 tons for thirty years or so and I still lean something every day . But I must worn you I CAN NOT SPELL Nice truck good luck with it and have fun

 

[Ma Duce]

Ryan -- the answer is they use gear lube the 80/90w will work.

 

[Dukeman]

I am looking at the Lubrication order right now because I am recovering a 931 this week. I am not shy about educating myself and taking time to read even boring stuff. I guess I do need help with the abbreviations, for engine oil on OE/HDO engine it just says 30. I am guessing this is 30 weight oil? I really don't want to guess. Is that how it is read. Then the transmission on the OE/HDO calls for 10, is that 10 weight oil? It really is a little confusing, they don't really tell you what you are looking at.

Steering system also says 10. Really? I mean its a great job of telling when to maintain, what intervals, lube points etc. But can someone actually direct me to something that tells me what types of fluids to use? Engine oil, transmission, transfer case, power steering, brakes.

Also what type of batterys I am going to need to bring with me, assuming the batteries need to be replaced. Is there a recovery thread somewhere?

Thanks!

 

[juanprado]

The engine oil is 30w detergent. Most folks use 15w40 fleet oil. They are perfectly ok to use and mix. Just make sure to use a name brand fleet oil for diesel. I believe the total capacity is 7 gallon so a gallon won't make any difference and you will be changing the oil when you return home anyway.

The transmission oil has 2 different choices. The military does use 10w oil in the transmission and power stg. Napa does carry it if you need to find it.

I would recommend checking your dipstick first. 10w oil looks like motor oil or hydraulic oil with a yellowish sheen. The automatic allison tranny does also use Dexron in the civilian world. My m923 came with dexron already in it when I recovered it. Dexron is a redish fluid and easy to id. To be safe bring both. They are compatible to mix but I would just use whatever is in there and not mix. Many threads on flushing it all out to dexron or the Allison proprietary fluid. Personally I don't think 10w is the best as it does not have the additive package that tranny oil does.

Power Steering fluid is also very close to 10w and has anti foam additives. I would just use commercial everyday power stg fluid.

The batteries are military square 6tl batteries. Only the military uses this size. They are available at NAPA or Interstate. Cost more but fit the cables and hold down perfectly. There are many thread on substituting 8d or 4d or group 31 or 24 using one big one or 2 or 4 regular size. Check height and you might need to make blocks to space the batteries or modify the hold downs. Personally I kept the 4 military batts and have never had an issue. I start it every week or 2 and let it run. They have immense reserve capacity when you have 2 in parallel and series. I don't live in a cold area but appreciate the reserve capacity especially since I did have a fuel priming issue once and had to crank the beast repeatedly over and over. The military uses 4 for a reason.

Welcome to the club. BE safe and have a good recovery!

 

[Dukeman]

Okay, so I did read the TM correctly. Thanks Juanprado! So is the brake fluid DOT 5? I just got a call from GL and I am set up to recover on Thursday at noon. They said the truck will definitely need batteries, but other then that he said it is a nice tractor.

 

[RIDDLE1]

Great info!

I checked the trans on my 923 today( I just got it home yesterday) and noticed I have the 10w in mine. I also noticed that it was over filled. It is probably 3 inches over the hot mark. Do you think that will harm anything or should I drain some our?

 

[juanprado]

Duke,

You have straight air brakes not air over hydraulic.

Riddle1,

Yes, that does not sound ok. I would test drive a short ride and get everything to operating temp and recheck dipstick. Are you checking it with the tranny running in Neutral?

 

[RIDDLE1]

Yep. I checked it after a short run from where it was unloaded to my house. I noticed the temp gauge for the trans was pegged so I checked the fluid to see how hot it was to see if it was just the gauge. The fluid was not to hot to touch so it is a faulty gauge/sending unit I guess.
I guess I will drive it again and recheck it. If it is still to high I will drain some.

 

[Dukeman]

oh, yeah, juan, I knew that, ha ha, sorry.

 

[juanprado]

Riddle,

There is a drain pet cock under the hood by the trans cooler. Just follow the spin on t- oil filter. It looks like a regular drain valve.

Juan