Community Forums

tmaxx · 05-12-2021, 03:25 PM

I have a 2003 29' Class C Ford E-450 with 50k miles on it. I tow a car behind.
As I understand I need to change the rear differential fluid. I am having difficulty finding which diff fluid to use. The tag on the diff cover is:
4.56 V2C24 BA
606803-3

From below owners manual it looks like 80W-90 is the right diff fluid, correct? Some have mentioned using 90w/140 diff fluid but I can't find this anywhere.

I'm not sure capacity yet. Looks like it's either 3.1L or 3.5L.

Sweetbriar · 05-12-2021, 07:36 PM

You have a Dana 70/267 with a 4.56 gears. You should use 80W-90 lube that meets Ford's specification. Don't worry about if you need 3.1 or 3.5 liters. Just get a gallon jug and refill so the oil level is up to the fill port on the back cover. Once it over flows the fill port it has enough. And also get an oil transfer hand pump which will make life a lot easier refilling the pumpkin.

amosnandy · 05-12-2021, 07:45 PM

Quote:

Originally Posted by tmaxx

I have a 2003 29' Class C Ford E-450 with 50k miles on it. I tow a car behind.
As I understand I need to change the rear differential fluid. I am having difficulty finding which diff fluid to use. The tag on the diff cover is:
4.56 V2C24 BA
606803-3

From below owners manual it looks like 80W-90 is the right diff fluid, correct? Some have mentioned using 90w/140 diff fluid but I can't find this anywhere.

I'm not sure capacity yet. Looks like it's either 3.1L or 3.5L.

I had to have mine changed out in Mexico due to a flood. Ford specifies a full synthetic which was $35 a quart and my f53 required 12, but they also say the diff is a lifetime lubricated item. No need to change. Guess I am not a believer in that and I changed it twice with semi synthetic 80/140 The hardest part on your will be getting the old oil out. My F53 had a drain plug but I think your class C 450 does not, You have to take the bottom bolt out of the cover and go take a nap and have a few beers while it drains. If possible save the oil into a clear container and let it settle. Water and other contaminants witll show up.

Coarsegold · 05-12-2021, 08:30 PM

I would not change it at 50k maybe at 80k but if you must don't use 90-140 unless you operate in extreme high temps 100% of the time. Follow the mfg recommendations.

mytimeyet · 05-13-2021, 12:19 PM

As a PSA - Remove the Fill Plug first. It can be one of the worst feelings in the world to be laying there wondering how you will be getting oil back into the differential after you have just drained it and the fill will not budge.

Coarsegold · 05-13-2021, 04:52 PM

What a great point to make............

HarryStone · 05-13-2021, 05:58 PM

Quote:

Originally Posted by mytimeyet

As a PSA - Remove the Fill Plug first. It can be one of the worst feelings in the world to be laying there wondering how you will be getting oil back into the differential after you have just drained it and the fill will not budge.

That would lead to determination...

GypsyR · 05-13-2021, 08:54 PM

A matter of perspective. To me such a fill plug would be"Aha! A challenge!" One of my actual favorite sayings about such things is "Resistance is futile!"

But anyway. For many years it has been my habit that when I change any rear gear oil I upgrade and update it to full synthetic 75W-140 oil. Whatever name brand is handy and a step above Supertech basically suits me. Some rears take different fluids and even additives too, but none of that info applies to us in this thread (unless someone has put a limited slip rear in theirs. )

An old and now retired mechanic once told me "I never once saw anything fail because someone changed the oil in it too often."