95 Monte Carlo Z34 with 4t60-e transmission. The transmission will shift into 4th by 30 MPH unless I floor it. Downshifting is worse. It will not shift from 2nd to 1st until its almost stalled. 4-3 is ok. 3-2 is not good. 2-1 is terrible.

I have replaced the TPS, and recently went into tranny and replaced all 3 shift solenoids and the TCC/PWM. I completed the TPS/ISC adjustments.

Just pretty lost as where to go next.

 

Converter locking up?

 

in 2nd gear it will continuely lock and unlock. The car will lunge and release, back and forth. 3rd gear at extreme low speeds will to. Since I replaced all the solenoids in the tranny it has improved alot. Only really happening in 2nd gear. The only things that have not improved are the shift points. Be it up or down shifting.

 

im curious....as your driveing thru the gears....does it shift hard? or kinda sludge its way thru the gears?

 

if casually driving, it will shift to 4th before i get to 30mph and its smooth. If you get it on from a stop there are long delays to shift. You can here the shift start then 1 or 2 secs pass before it shifts. If you attempt to downshift manually you think you got rearended.

 

Is there a way to reset the shift points? Its like it doesnt know when to shift. The GM manual was saying at least 40-45mph before it should go to 4th. I am there at 28-30mph.

 

What you think is 4th is probably the torque converter locking in 3rd

 

I know theres a way to adjust them thru the computer..youshould go to a trans shop to have that done....

When i had my trans rebuilt....they up dated the programming for the shift points.

Mine shifted (like being rearended) when i manualy shifted mine before the rebuild...of course now its smooth and chrisp like it was when it was new....

It maybe time for a rebuild....
How many miles on it? I did mine at 135,000

Its really hard to say...maybe the converter as suggest before....
could be a pump.....I think ultimately i would take it to a trans shop for a professional opinion....
If you lived near me in Michigan...I know a guy that owns a trans shop that would hook you up....

 

knock on wood i am at 150,019....no problems but replaced shilft silonode