Changed transmission fluid (class C E450)

[jabrabu]

I just changed the transmission fluid on my 2018 Chateau (Ford E450 chassis). It has the 6-speed, and the maintenance schedule says to change it at 150K miles, but the towing schedule is every 30K miles. Mine has 60K miles on it and we sometimes tow a CR-V behind it, and I decided that it was time to change it.


On the dipstick the fluid still looked pretty good, but when draining it I could see that it was actually fairly dirty.


I dropped the pan and replaced the trans filter, and cleaned the magnet at the bottom of the pan. The magnet had a decent layer of black sludge on it, but nothing unusual.


The capacity listed is 17 quarts, but even though I dropped the pan and replaced the filter, it only took 10 quarts to fill it. I guess there is still a fair amount of fluid that remains in the torque converter and trans cooler.


So, at 60K miles the fluid definitely needed replacement, and cleaning the pan and magnet and installing a new filter was a good idea too. In the future I plan to do a drain and fill at 90K miles and another full fluid and filter change at 120K miles.

[The_Breeze]

Thanks for sharing your insight.

[Judge]

That is why the shops usually do a "flush and fill" for transmissions. There is a lot of fluid that does not drain out of the pan. You probably still had about 6 or 7 quarts of "dirty" fluid in it.

I know some people that don't have the tools to do a full flush will drain it, refill and then drain again to try and get as much of the old fluid out. Then they change the filter after the second draining.

[jabrabu]

Originally Posted by Judge

That is why the shops usually do a "flush and fill" for transmissions. There is a lot of fluid that does not drain out of the pan. You probably still had about 6 or 7 quarts of "dirty" fluid in it.

I know some people that don't have the tools to do a full flush will drain it, refill and then drain again to try and get as much of the old fluid out. Then they change the filter after the second draining.

Thanks. I've heard mixed advice on doing a flush -- some folks say they can do damage. I've also heard of some folks disconnecting a line at the trans cooler and then running it to pump fluid out. I figure if I do a drain and fill every 30K miles the fluid will remain fairly clean.

[Judge]

I have a 2018 GMC Canyon with the 2.8L Duramax Diesel and Allison Transmission. The manual calls for the transmission fluid to be changed about 80,000 miles. I was having some torque converter shudder shifting from 2nd to 3rd gear and after reasearching it I learned that GM was recommending a full flush with a special tool from GM and a better grade of tranmission fluid. I took it to the dealer a few months ago at 50,000 and the flush and fill fixed the shudder shifting from 2nd to 3rd gear as I had read.

I was going to do it myself until I read about the flush correcting the issue and then also finding out the transmission had to be refilled with a pump from underneath the truck because it doesn't have a dipstick.

If you change fluid ever 30,000 miles and use a high quality synthetic fluid, you will be just fine.

[jabrabu]

Now I'm thinking it's time to change the rear differential/axle oil. It doesn't have a drain plug, so I guess you have to remove the rear diff cover to drain it. I could do this myself, but I'm not sure if I want to. I'm planning to get my rear tires replaced soon, and I'll see if the tire shop can change the rear axle oil. If not, I'll do it myself.

[mcr1010]

Originally Posted by jabrabu

Now I'm thinking it's time to change the rear differential/axle oil. It doesn't have a drain plug, so I guess you have to remove the rear diff cover to drain it. I could do this myself, but I'm not sure if I want to. I'm planning to get my rear tires replaced soon, and I'll see if the tire shop can change the rear axle oil. If not, I'll do it myself.

I changed the diff. fluid on our first MH a few years ago. It did not have a drain either, so I used a hand pump like the one from Harbor Freight to suck the fluid out and refill with fresh. Worked just fine without having to remove the cover.

[jabrabu]

Originally Posted by mcr1010

I changed the diff. fluid on our first MH a few years ago. It did not have a drain either, so I used a hand pump like the one from Harbor Freight to suck the fluid out and refill with fresh. Worked just fine without having to remove the cover.

Thanks for the tip!

[Pete'sMH]

I’ve thought about this service on my class A. I expect to be at 25-30,000 miles at five years and if I see myself continuing to RV for a while I’ll probably just go to my Ford .truck place and get new tires along with transmission, differential, brake, wheel bearing and maybe other service. It’ll be a spendy service visit but that’s likely what I’ll do!