I just finished rebuilding my 4R70W transmission. It was a 1996 and had 210K on it, slipped in the morning when it was cold ... got better as it warmed up. This is actually in our E150 van (suprised it has held up ... heavy van with high top and wheelchair lift for my wife) but I have the same transmission in my truck and there is no E150 forums.

Put new clutch packs, O/D band and seals in it. Also a new converter and pistons.

Went to test it, no O/D!

At 50 mph, it changes gear and the engine rev's but no gear! At first I thought it may be third gear but when I turn off the O/D it stays in gear after 50 so it must be 4th that I messed up!

Any idea what I may have done wrong! I know it must be something I put together wrong because it worked before I rebuilt it.

Is there anything in the pan I can check (I completely dissasembled the valve body) or do I just need to pull it out again and start from scratch?

Thanks ..... Mike

 

If you lost overdrive you probably have a problem in the overdrive band. Might have missed the band with the servo rod.
Alan

 

I actually got up in the middle of the night thinking this could be the problem.

During assembly, I noticed I "missed" the band with the rod (I still had the pump off).

I then took the piston out, help the band in place from the front of the transmission and then put the piston in so it hit the band (took 3 tries).

It would be good for me to check this before I drop the entire transmission again.

How can I hold the band in place from the bottom of the transmission? I know I will miss it if I just take the piston out and put it back in. Is there some kind of hole (obviously under the shift plate assembly) where I can push on the band and hold it in place while pushing the piston up?

Any other things to look for if I pull the pan off?

Thanks .... Mike