Fluid Change in Rear Diffs and Trans
 

This weekend I was planning on changing out the gear lube in a truck I just bought. How many quarts go in the rear diffs??? How much fluid is needed for a Eaton 13 speed??? The application calls 75/90 synthetic for the diffs and 50w synthetic for the trans. I all reality is any brand better than the other?

Thanks in advance for the help - Todd

It might be just as easy to have a shop do the changes. You will not save much by doing it yourself and it is less hassle. I do my own services on my truck, but even I have a shop usually do tranny and diff lube changes. Just not worth the time involved. There is really no major difference in brand of lube oil. Since you are online anyway, go to Eaton's website and download their lube manual. They show recommended brands and specific lubes under that brand that they recommend. If I recall, even Chevron Delo brand in a conventional oil meets the requirements of synthetic for the warranty of Eaton stuff. I would have to go back to the manual and confirm that.

i'd just go to speedco..$350 i think it is with all 3 changed.. all synthetic and i some lucas also.

I will check out speedco and see what they are at. I called a couple local shops and they were looking at 250 a diff and the same for the trans. Also no one around here is open in the weekends. During the week we are rolling pretty much non stop. We run the truck as a team. This weekend we both have commitments so the truck will be home and available for service. I called a Petro which isn't too far away and they too were at the same prices as the local shops.

OK Speedco according to the website can drain and refill the boxes for under 400 bucks. I can't buy that much synthetic fluid for that.

Synthetic lubes, regardless of brand, are pretty darn good in and of themselves. Not sure how Lucas would help. It is just a base oil. And, you ought to see what happened to Lucas in the testing done at - Bob is the Oil Guy

Not pretty.

count on a pail for each, if you are going to do it yourself.

Depending where you are, get those pails nice and warm inside before you try to pour...

You need a length of hose that will go in the fill plug and a funnel that fits tight to the hose.

And a lot of patience, it takes awhile.

Almost 5 gallons for the trans, 4 gallons for the front rear and 3 1/2 gallons for the back rear, you will need a pump to get the oil into the rears, funnel and hose won't do it no matter how warm it is.

That being said, Speedco is where I take mine now, I can't do it any cheaper than they can

just changed mine last week. trans held 2-1/2 -3 gal. funnel worked great. metal funnel with screen. rears take approx 3 gal. each. used 5 gal bucket with hand pump. j-t -7 90/140 for rears. 50 wt for trans

It is true that you should go for service at stores, it will not take much from you, sometimes the issue is vulnerable and we should not take it for granted, better to take help from service station.