I have the 4L60E, and for some reason, it won't shift when I go WOT from a roll. However it will downshift when I am going lets say 50, it will downshift, bring the RPM's higher, but it won't upshift, i keep bouncing on my rev limiter.

Also, the transmission feels somewhat "retarded," meaning that the shifts aren't firm.

Last Saturday I changed my transmission fluid, put Proline Dexron III fluid, and I changed my gear oil, put synthetic gear lubricant in that. I also changed my transmission filter. There are no leaks.

My car is running somewhat lean also, SES light keeps coming on and off.

I was going to have combination motorsports do computer tuning anyway, but do you think this will cure my problem?

Thanks for the help

 

Ah yes the wonderful 4l60E. I don't think tuning will help it any. The damn computer is just stupid. My car does this sometimes, especially from a 50-60 mph punch. The TC will come out of lock-up and the car will downshift only to have the engine hit the rev-limiter as the TC doesn't looks up soon enough. It then locks up, the car lunges forward then unlocks again for some reason until I lay off the gas and reapply it. It only does it from a 50-60 roll so I just don't get on it from there anymore. If you find the cause or a solution please let us all know. Thanks.

 

well i got my problem fixed the car was running very lean and the tranny was bogging down a little

it was just a vac leak cost like 60 bucks to get fixed doubt this is your problem but it might help

 

Just to see if it will do something, I will try and reset my PCM, see if that helps. Thanks for the feedback

 

sounds like you need a rebuild to me....

but who am i? just an lt1 guy...


my 4l60e did the same thing... before the 2-3 clutchpacks went for good

was the fluid burnt when you changed it?

changing the fluid actually brings this on, if it was gonna happen... fluid drain brings it on... same thing with me

sounds like your clutches are starting to slip



if you redline it, it won't shift, but if you let off a little, it will...

right?

 

What do ya mean by burnt?

Well after 40mph, after I go WOT, it will downshift twice, from third, to second, then first, and then it will bounce off the rev limiter. It's fine if I go WOT below 40, it will perform just fine.