jeremy449

My 2004 F150 Supercrew 4X4 has 90,000 miles on it and as far as I can tell, it has never had a trans filter change or the rear end fluid changed. I have heard both stories in that 1) a fluid change is good for it at no matter what the mileage is and 2) that if I change it now, it will start slipping. It's not slipping now and seems to be running fine.

Any experience in this either way?

Mod (Ret.)

Get the rear changed; have the cover removed, cleaned, and fresh gear oil. If itsa limited slip (code on the drivers door jamb), have the special additive added too.

As to the transmission, I'm a huge fan of transmission flushes, but with your high mileage and no records of previous fushes, I'd recommend having just a pan drop and filter change. You'll only get about 5 quarts of fresh trans oil, but it is better than nothing, and you'll get the filter changed.

donbun68

I changed the fluid and filter in mine at 94k and didn't have abit if trouble afterwards. Just remember if you do change fluid and filter, pan gasket is reusable.

dereku

Did mine at 94 too with no issues. I added a deeper aluminum trans pan and mobile 1 full synthetic and it runs great and shifts great.

And it was the first time it was done. The factory plug was floating around in there still.

BISCUT

Mine is 04. Did my trans filter around 62k and all good. I did pan drop n filter and added PML pan. Makes for easy fluid change. I'd do pan drop and filter change and be smiles.

SuzukiRider

At our shop we will do a flush up to 100k. After that, with no records we dont touch them. Diff change is also a good idea, considering the clutches in the differential.

jeremy449

What is a PML pan?

Deanjet

http://www.yourcovers.com/

What automatic transmission does an 06 F150 have? The web site list the following choices:

4R44E, 4R55E, 5R55E, A4LD Deep 9614-2
5R55N, 5R55S, 5R55W Deep 11066
AOD, AODE, 4R70E, 4R70W, 4R75E, 4R75W Low Profile 9324
AOD, AODE, 4R70E, 4R70W, 4R75E, 4R75W Deep 9685
C4 Deep 10453
C6 Deep 9592
C6 Low Profile 11064
E4OD, 4R100 Deep 9323
5R110 TorqShift, Old Style – External Filter 9973
5R110 TorqShift, New Style – Internal Filter

Guy9smiley2

Change the rear end fluid and make sure you put the xl-3 modifier in it. Aldo for the trans go ahead and do it up. A common misconception is that the flush wrecks the tranny, the flush does not. If after a flush a tranny goes bad it was already going but the material build up was holding it together thus by flushing it and cleaning it all out and putting fresh fluid in the problem that was there tvat was un noticed is revealed.

jeremy449

Thanks for the advice - went to a trusted transmission shop today and talked with them - they are changing the trans fluid, transfer case fluid and read diff fluid. The mechanic says that I should be good and that they also have an additive for granny's in this shape (high mileage without services) that will prolong the life. I will keep you all updated