Ford E350 Rear differential fluid change

I haven't done it on an E350 but I did on my Dodge 3500 truck. It can't be much different. Loosen the bolts, leave the top couple bolts in a little bit, and let it drain. Wipe it clean, assemble, and refill until it comes out the fill hole. I believe I reused the gasket and it hasn't leaked in several thousand miles. Hope this helps you some.

Yup did mine the old fluid was aweful I added gearzol www.sfrcorp.com to mine runs like it should

I tried to locate the right gasket and failed went with the grey permatex rtv no leaks at all. Its way better then the rubbery silicon stuff Imo

The big thing with this job is to lift the frame as high as u can I used my rear stabilizer Jacks and of course some jack stands for added safety

If it's gold your good even slightly amber dark was what mine was from extreme heat that's why I added the gearzol for ep protection

I waited a couple hours for the rtv to cure and am very happy that it got done I would do it every 30k cause it's way cheaper then a new rearend is highly neglected on most all vehicles

fourthclassC wrote:
Howdy, Has anyone changed rear diff fluid on e350 class C? If so, how did it go? Thank you

Went great till I saw the price of new oil.

What exactly do you want to know?

Suck it out with a slurp gun or vacuum tank! I used the "Topsider" that pulls the oil out of the V8 in our boat. No messing with a gasket or RTV sealant to reassemble. Best lube game in town is Walmart's Supertech 75-140 Full Synthetic, about $12 a quart. They sell a "Blend" version for about half that, but you can consider an axle with Full Syn in it as Permanently Lubed unless you get water in it. Use a short piece of fuel hose over the spout on the oil bottles. Cut the spouts so the hole is big. Warm the lube in the sun or pot of hot water and squeeze'em in.

Oh, the Fill Plug (1/2" hollow square for 1/2" ratchet) has a magnet on it, at least with a Ford. Ours was clean. No need to worry about draining out what's at the bottom. Just use suction. Check level before pulling the lube out. Measure what you removed to be sure you took the full capacity out. Then refill. Goes to just below the bottom of the hole, again for Ford.

Also, pull the oil out after a road trip, it'll be thinner and pump more easily. I was shocked how well the Topsider (also known as Oil Boy) got it out.

I would never use an extraction machine on anything I own! and would run as far as i could from any shop that uses them if i needed emergency service on the road.

Especially on a rearend. Mine happened to be in severe service range probably cause its always overlooked. The sludge will never be wiped out and any metal filings which rarely ever make it to the fill plug magnet would stay in there indefinitely! Just recirculating over and over until catastrophic failure.

Its also a good time to inspect the ring an pinion for uneven wear and or pitted bearings that can cause major issues over time. Rv's are more susceptible to pitting cause of the sitting time.

extraction machines, Flush machines and tourque sticks DO NOT BELONG in any shop and should be banned. I can't even fathom how much damage these things have caused people over the years.
Great for the shady lube places and shops that use them they make money on the service and even more when it trashes the drivetrain they are servicing.

Sorry they sound good and promise to make quick time of the task at hand, but nothing replaces quality work and proper inspection.

The above blanket condemnation of oil extraction is not accurate. Extraction is used in dealer service of Mercedes Benz vehicles and others. Many vehicles have 150+ K mile engines on nothing but oil extraction and replacement.

If the differential has a ton of miles, I can see pulling off the back cover and taking a look and wiping it out. Even in that case extraction is a lot better than nothing.

Extraction is used professionally in many cases with the blessing of the manufacturer. In some instances it may be the only possible method to change the fluid with part in installed position. It is a valid tool in the toolbox.

I changed the differential fluid on my 2005 E350 because the cover developed a leak. Found out Ford doesn't use a gasket and I couldn't find one. After careful research I found that there is a silicone based material that is compatible with differential fluid. Think it might have been Permatex? Not sure. You have to remove all the old silicone and make sure the mating surfaces are clean and, after bolting it back together, let it sit overnight before you fill with fluid. It's been 15,000 miles and a year and a half and no leaks.

I wanted to get the fluid changed and had been procrastinating. A friend from the Class C forum encouraged me to 1. use a suction device, and 2. refill with 75W-140 Full Synthetic. Since the magnetic plug was clean, the axle was full, and was quiet, I just jumped in and did it. It wasn't just that I didn't want to take the Track Bar off to even get access to the cover bolts... I didn't have a good reason to do it. Between the fuel tank, the exhaust, the shock, the sway bar, storage compartment and mud flap, it was challenging enough to get the quart bottles in place to refill. Glad I didn't have more to do than I went through on this job.

As long as I was pulling the cover off I put on a finned aluminum with drain and dipstick.

What mileage? I think differential oils on lighter pickups are consider lifetime.
I did change the oil on couple of my duallies.
Not a biggie. Synthetic oil is expensive, but you need 2.x quarts so no need for 2nd mortgage.
Fords don't have gaskets, so buy hi-tech Permatex and apply it one day with finger-tight bolts and torque following day.