ZeroIce

I drive a 2000 Chevrolet Z71 1500 Truck. My transmission shifts from 1st to over drive when I accelerate. I have a 560 cam, mas air sensor and 80mm throttle body. Does anyone have any solutions for this problem?

FLT

iTrader: (1)

I would think that you have an issue with the 2-4 band or an issue with the 1-2 accumulator. Some will argue the band failing if in fact you still have 4th gear however I have seen it happen. Are you sure that you are getting 4th or is it possible that it is 3rd? Do you still have reverse? If you do not have reverse then you have a broken sun shell and then your trans is definitely shifting 1-3. Hope this helps. Vince

performabuilt

iTrader: (25)

I am not clear on what you mean do you mean it just always shifts straight from1-4 or do you mean when its floored it shifts stright to 4th ? and can you manual hold the gears tokeep it from shifting

ZeroIce

Thanks for your response to my question. Here are the answers you need to possibly solve my problem.
1 - Not always, only when it's floored.
2 - No, when it's in manual it still shifts by itself.

performabuilt

iTrader: (25)

Do you have a tuner so you can change parameters

ZeroIce

No, I do not. What kind of tuner should I get?