Transmission servicing

[Josh99]

I want to change the fluid in my trans. I've heard that you dont want to get it flushed because it will stir up whatever is in the bottom of the pan which makes sense to me. I dont really have time to do it myself so I want to make sure whoever I take it to will do it right. Isn't there a filter cartridge in there somewhere? Dont you need to drain the converter at the same time?

[Fireman40]

I want to do the same. I have never serviced a tanny before. But im pretty sure if you unbolt the pan the filter is right there. Then you can clean the pan up really good with brake cleaner, put it all back together and fill it up. Am I right about this? IF not I would like to know So i can get it service properly

[Josh99]

Yeah and you have to drain the converter too. There's a youtube video on it

[wingnuts514]

there is a filter and a magnet so i don't see how flushing is going to stir anything up. But dropping the pan to change the filter and inspect for metal shavings is the best thing to do. p.s. alittle bit of metal is normal, but if it's more than 1/2 a teaspoon there could be a potential problem.

[zpd307]

drop the pan, the drain plug on the pan makes it so much easier and cleaner.... the filter just pulls down. clean the pan with you favorite cleaner, mine is brake cleaner. push on new filter and reinstall pan. the gasket is reuseable. fill back up with 6/7 quarts. some years do not have the tq convertor plug to drain it. read this to flush the system.... 4R100 Transmission Fluid Change - Ford Truck Enthusiasts Forums

[hansel]

Here is what I've read about tranny service, you drain the pan and replace the filter, you will have drained about 6-7qts of fluid. Next remove the tranny return line and run it into a drain pain, I will unhook mine at the Magnafine filter and run a 3/8" hose into the drain pan, you then start the truck pumping out another 6-7qts., fill up another 6-7qts, pump out another 6-7qts., do this until you have changed 19qts of fluid. This will flush the old fluid out and you will have replaced it with the fresh fluid. Also when doing this during one of the steps run the gear shifter through all the gears to make sure it all gets flushed out.

[Highbeam]

Here's the problem with that method. Our transmissions have a thermostat so they only flow oil to the coolers when it is hot. How hot? I don't know. But if you're not careful you will end up with a non flushed cooling system. Maybe no big deal?

[cj45lc]

Our trans do not have a thermostat they have a pressure by-pass. The way hansel described is the way to go. Did mine a couple months ago & worked out fine. I did run mine for awhile to get the trans warm just because I thought the fluid would flow better & maybe get more of the gunk out of it. BTW the guy that put the procedure up was a Ford trans engineer, believe he knows what he's talking about.

[kitchene]

What kind of fluid do you guys recommend when fillin' it back up?

[mas360]

Straight Devron III/Mercon as recommended in Owner's Manual.
Ford releases a bulletin switching from Devron III/Mercon to Mercon V. But I've heard of people having problem with Mercon V causing failed seals. If your transmission is recently rebuilt it is ok to use Mercon V due to new seal material is compatible with it.

To be safe I stick with Devron III/Mercon. It is cheaper than Mercon V anyway.