what lubricant goes in a manual transmission? I

Ive got a 53 footer full clear to the doors of what must be every type of oil known to man... You should see the BOL, it's seriously nearly 1/2 inch thick!... Quarts, gallons, 5 gallon buckets, 30 gallon drums... Motor oil, ATF, gear oil, grease... I swear if Valvoline makes it I've probably got it back there.

 

If it’s a Eaton manual transmission, you are to use Eaton fluid only. It’s expensive.
You can get same weight for a few bucks cheaper at Napa if you are a cheap skate though. Only the recommended for my livelihood though so do as you please

 

There are a lot of posts on here already and still do not know what transmission you have.
Some places have really good prices on services, do a good job, and will take care of that for a couple dollar charge.
Now is there one of those anywhere you are going when you need a service.

 

Use Eaton. Every dealer carries it

 

Wow, that’s the first I’ve heard of such a thing, interesting.

 

So what’s an Eaton manual w/ auto shift considered? A manual or an automatic. I can’t fault the OP, I have no idea. Lol I’d have to stick my finger in there and maybe smell it and taste it.As far as Eaton only brand. I used an off brand called Super S 5 gal. Synthetic Heavy duty 85/ 140w in rears along w/ equivalent 1 gal Synthetic Lucas. Same brand 50w in trans w/ 3 qts. Lucas 50w. After at least 700 k it still looks good. Rears got over 2 mil now, trans 1.1 mil. Made at a small Independant refinery in Louisiana. About half the price of name brand. Bought at the company store. I used Lucas just in case. Lol. It’s expensive. The Super S gear oil is a good product. They also make Cam2 oil products. It’s sold nationwide. The Guys got a small goldmine with that business.

 

Synthetic 50w for an eaton auto.
Newer oil is now called a synthetic 75-90 TRANS oil not to be confused with the more common 75-90 diff oil

 

I haven't priced it and doubt that most dealers stock or sell much of "Eatons" fluid. We stock and sell Mobil products which most all major fluid manufacturers have an approved fluid for applications.

Eaton recently released a new trans fluid spec which is 40wt. PS386 and is backward compatible on all manual and automated trans. We are phasing out remaining stock of 50wt and yes it's more money.

I once had a tech service an Allison 4500 and filled the trans with manual 50wt trans lube because the lube looked brown/yellow.............they do in garbage truck..........yea he got fired.

Step 1 Verify what your working on and Step 2 look up the correct fluid

https://www.google.com/url?sa=t&sou...FjAAegQIBBAB&usg=AOvVaw3RU_yOUknaChVK7JCg-Whs