I swaped my slipping 4L65E with a built on today. Only took 6 hours Had a few driving issues at first which I wrote off as air in the tranny fluid lines or converter . After some driving it cleared up, ...so far. I put in a 2200 stall to replace the stock one and am still getting used to it, almost feels as if is slipping when I get on it. Any lessons learned or common experiences after a tranny swap like this? All opinions and info is appreciated. This is my first tranny project. I had a mechanic helping so I'm pretty sure it is put together right. Has anyone ever heard of a breaking in period for a tranny? I was told the belts, clutches etc, have a preservative on them at first and as this wears off the tranny will grab better/shift harder.

 

i would have the tune updated with a little more pressure added to the trany,
just enough to feel a slight jerk on the 1-2 shift.

 

Did you make sure the converter was seated all the way? Once the trans was bolted up the converter turned freely?And you had to bring the converter into the crank approx. 1/2"before the bolts went in? And is it full of fluid?

 

When we put the TC in we did the old 1, 2, 3 turn until it was set. We (he) then tightened the 3 bolts that hold the TC against the flywheel. They didn't bottom out on the converter so they should have been good and tight. After I had the "vibration" during the intiail run after install we droped the starter and the flywhell cover, turned the flywheel and checked all the TC bolts and they were still tight. The vibration is hard to describe, when I gave it a little throtle it felt like gears were slipping over each other and causing a vibration but the truck still moved. It did it once in reverse and then once in "D". The consensus among the guys in the shop was air in the lines that had to be "burped" out. When he tightened the 3 bolts the converter did move forward a little but I was told that is normal. I drove it about 10 miles home and goosed it a little here and there and never got another vibratrion. I don't know....more driving tomorrow.

 

Had an errand to run this morning. Forgot about the tranny issue and drove it like I usually do Anyway right outside my neighborhood you have to merge into the highway traffic. I stomped it, go about 5 #'s of boost and when it went from first to 2nd it grabbed hard and felt like I got sling shot'd out into traffic. Pretty awesome except it almost put me into the persons bumper in front of me... So I thought, sweet the problem is gone. Then on the way home I played some more and it seems as if the computer is confused on when to shift down when I get on it from a cruise speed. And I swear it still feels as if it is slipping sometimes. Is the stall (2200) confusing me into thinking it's slipping? Is there a breaking in period or a computer learning period I don't know about? Fluid is full, check it twice a day. Can a dyno tune identify and correct these tranny issues if it is the computer and not hardware?

 

you might need to have it tuned on the street.

 

I recall something needed to be changed when you go to a looser converter (in the PCM). I'll try to find what it is. It could have been crap that a previous tuner had said though.

 

I sent Lyndon at Westers an e-mail about it as well. If you find answer please post it up. With all the guys on here with Yank 3000's I would think the answer would be easy to find. I'm calling my tranny shop in the morning as well.

 

Thats what I'm thinking. I know mine had to be street tuned a little because it would wait a few seconds after punching it to downshift. Might be the same problem you are experiencing.

 

You had the 60E right and swaped it out with the 65E? Good that it worked for you.