jensen41455

My truck has started to make a weird noise coming from what seems to be the transmission. I wouldn't call it a howl or a whine, but somewhere in between. It only seems to make this noise in first gear. Once it shifts, it goes away. I've run it up to 3500 rpm in first and the sound is horrible. I shift in to second and no matter how fast the engine turns I never hear the noise. I checked the fluid and it looks to be in good shape. A buddy of mine believes that it could be a needle bearing in the first gear planetary going bad and that sounds logical to me.

I was given a quote of "up to $3,000" to rebuild my transmission. He said it could be less, but wanted me to prepare if it's not (already makes me think I'm getting scammed). I understand that he doesn't know for sure what's wrong until he opens it up, but I've just never liked the idea of someone else working on my vehicles. It is this reason why I've decided to dive in to the world of automatic transmission rebuilding. I found a transmission out of an identical pickup with 260,xxx miles on it for $100 that I'm going to rebuild so the wife can continue to have a vehicle to drive while I fiddle with rebuilding this one.

Anybody here ever rebuilt a 4R70W? Any tips or tricks I should be aware of before I start? I've done some searching online and found a few articles and what-not, but you can never have too much information.

Just so you know, I have a 2002 Supercrew 4X4, 5.4L, 4R70W, 150,xxx miles. I do a fair amount of heavy towing with it so recommendations on upgrades would be good too.

7700SCREW

Good luck! I respect you for attempting an automatic trans rebuild on your own!
It's the brain surgery of the automotive world!

Make sure to take pics and write notes of the way everything comes out.
Make sure your work area is very clean and lay all your new parts out on a big table in the order there going in.

Have you ever seen the inside of an auto.trans.?

jensen41455

I've pulled the pan on mine. That's about it other than a lot of pictures on the net. I'm pretty mechanically savvy, but I am in no way under-estimating what I'm potentially getting myself in to. I know it's a big undertaking, but I like challenges. We'll see if I still feel that way when I'm done. I'm only $100 in to my donor transmission so far so if I decide it's too much for me once I break it open I can throw in the towel with minimal loss. I'm planning on taking a lot of pictures and hopefully I'll be able to post up a tutorial of it.

guinelle1

sorry to bump an old thread, and im new here but im having the exact same issue with my 4R70W. Did it end up being the first gear planetary?

even if jensen is not active anymore anyone have an idea of what it could be?

Carcrazygts2

If your symptoms are exact, then lts a needle bearing in the first gear planetary.