Darkmark454

Hello. I have a 2002 f150 5.4 2wd. When ever I give it a little more gas like to pass someone or start going up a hill, the trans down shifts and there is a hard thunk. Like it just slams into hear. Also have it when it shifts from 3rd to 5th.I did a quick search on the forum but couldn't find a post quite lime my problem. Seems to just skip 4th completely. The trans has almost 160,000 miles on it. And it has been doing this for as long as I can remember. Also how can you tell what kind of trans you have. I bought the truck from my dad about two years ago and he has no idea what kind it has. Planning on changing the trans fluid soon and I want to make sure I get the right kind. Hopefully changing the fluid will help a little. My dad said he doesn't think the fluid has ever been changed. Also do you guys recommend adding anything to the fluid. Like trans slip stop or something. I forgot what it is called. Thanks.

Carcrazygts2

You dont have a 5sp auto. You have 4 speed with a locking converter. Time to do trans fluid exchange. But if its over 100k miles, and has never had one done or hasnt had one done in 60k it may make the trans worse.

Autofair Truck Parts

i had a 94' F150 4x4 that had a 2nd gear kick, its a ford thing. all of my buddys who had older ford like that, they kick.

me1234

My 2000 4.6 Liter w/ 60k started doing the hard shift(not the weird downshift though) when I hit the gas sometimes too. Im gonna get it serviced soon and Ill give u an update on what happens

me1234

Also it recently started doing this. It disnt always do it(Ive had the truck since 40k miles)

Darkmark454

Ok. Thanks a lot.

Darkmark454

Why would changing the fluid make it worse. I have heard that draining the torque converter may result in damage. Is that what you are referring to. I was just planning on doing a pan drop.

ryno_rx8

Is it inside the trans feeling or can you feel it in the floor board? Mine has something similar and its a toasted trans mount

Darkmark454

Im not entirely sure where it is coming from. It could be in the floor board now that I think about it. The whole cab rattles from the severe thunk. I just assumed it was something in the tyranny. Is it relatively easy to spot a worn out mount. Never really looked at the transmission closely yet.

Randog1978

My '04 F150 has always had a funny "slip" in the drive train. Seems like the rear differential - but it's not. Replaced the tranny @ 50K miles - under warranty- barely. Now the "slip" feels worse than before. Noticed the transmission & xfer case move up/down when you power brake it, and this caused a "clunk" type of noice while under power & when you back-off the throttle. Local Ford dealer says "it's all good". Really ??