Do you have a part number?

this is the one I bought

Transgo Shift Kit SK 4L60E 4L65E TRANSGO SHIFT KIT® 1993 -2007 (SK4L60E)

I don't know how I forgot but I failed to mention something. When I took it for its test drive and it wouldn't shift, I turned around to head home. I kept pressing on the gas and I got up to about 35mph at 4000rpm (I think???) then I took my foot off the gas and there was a pop and a sudden jerk, and then it wouldn't go much faster than 25 mph even if I floored it to 5000rpm...

Alright I dropped the pan and valve body for the third or fourth time now... Double checked EVERYTHING again, took it all apart and put it back together per the instructs requests and it still will not shift out of first!!! I used one of the larger check balls where it suggested I put one but this time I put the regular one back and all the check balls stayed in the right spot I am sure of that. I checked all the valves, springs, actuators and everything and still nothing....

Ok get this, I jacked up the rear end so that I wouldn't have to keep pulling it in and out of the garade. I unplugged the electrical socket from the transmission to force it into limp mode, which I know only gives the transmission 2nd and 3rd gear. And it did. I put in in 2nd and the tires spun up to about 35mph then I put it into D and it went up to 60mph. Well I then dropped it and tried it on the road, but it still felt like it was in first and didn't go faster than 30mph in any gear... Wut???

https://blazerforum.com/forum/attach...ine=1435033689

Had this happen to me when I installed a corvette servo. Never found out why that happened but just make sure ring is seated. I have a full post over @ gmtnation under "4l60e upgrades, shift kit and new seperator plate".

I know the ring is seated good, I push in the cover then push all around the ring with a screw driver to make sure its in there.

Ok this is really strange. First off I'm not able to take it anywhere ATM as there is no exhaust on it. Secondly, like I said it is stuck in first but maybe its second... I jacked up the rear end so that I can drive it in my garage without actually going down the road. Had the transmission wires up so it had power and I put it in D and it went through all 3 gears and got up to 60mph at about 3000rpm. BUT when I would actually drive it, it wouldn't go out of first or faster than 25mph.... So I unplugged the wires to put it in limp mode, and that worked. I put it in 2nd and went up to about 35mph then shifted it into D and it shifted and went up to 50mph no problem. but when I do a real road test it stays in first EVEN if the wiring is unplugged. Sowtf...

First off I don't know much about the4L60E but I'm planing on rebuilding one. While doing my research I found this that might be helpful.


Starting about 20:15 till 21:15

Yes I have confirmed that if the rear end is jacked up and its put into D or OD it will shift fine. When I drive it on the road it will not shift out of first, what could be the issue? A fluid pressure thing or sensor?