texas99Z28

I've done numerous searches, and haven't seen a clear answer yet. When my tranny is in D(3rd) at 45mph, and I floor it, it downshifts to 2nd, and shifts fine into 3rd. It catches a 3rd at 75mph. When I have it in D from a dead stop, it gets to top of second, and bangs off rev limiter. I have read this is a tuning issue, and bands going out in the tranny. If it was a tuning issue, why would it shift into 3rd fine from a roll and not from a stop? I did have 3.73 gears installed, and they said they set it up for the speedo. Please Help!!!!! Don't know whether to pay $175 to have a shop set the shift points, or have tranny looked at by a dealer!

robsquikz28

iTrader: (246)

adjust your tps since your shift points are based off of your tps settings. first check that and fix it if it is a problem!!!!!!

texas99Z28

Not really mechanically inclined. how would I go about this?

performabuilt

iTrader: (25)

How many miles are on the trans? Fluid condition? But yes tuning is certainly a possibility as is the condition of the trans. I am no tuner but i do know that what happens depends on several different things, If the miles are not to high and if the fluid looks good then I would look at tuning. Setting up the speedo calibration may not be enough, Compensation for the increased rate of RPM rise during the shift would also need to be taken into account (More time allowed to make the shift" from command to actual .

Canada

iTrader: (2)

What if its been tuned already and then starts doing this? If OP hasn't had tuning yet I'd look at that. You could try and find a transmission shop to take a look at it for free or super cheap.

performabuilt

iTrader: (25)

Well if thee have been power adders used you would have to reset up and even other conditions that might make the car run faster would need to be considered.
And of course the trans could just be tired or have some other issue.
But I would definatley always look at whats being commanded first, If the shift is not being commanded then that would certainly not be a trans issue ever . And its the easiest thing to check

texas99Z28

Trans has about 64,000 miles on it. Tranny fluid looks good. I was about to have fluid and filter changed at a dealer soon anyway. Will they be able to see if anything is wrong with tranny while changing fluid and filter? Will a Tech at dealership be able to check shift points, etc.?

texas99Z28

Thank you everyone for the info.!

performabuilt

iTrader: (25)

They should be able to see signs of issues in the pan and with a scanner can observe commanded shifts

texas99Z28

I really appreciate all the info. If my tranny is messed up I may be contacting you about a built one!

PBA

"When my tranny is in D(3rd) at 45mph, and I floor it, it downshifts to 2nd, and shifts fine into 3rd. It catches a 3rd at 75mph. When I have it in D from a dead stop, it gets to top of second, and bangs off rev limiter".

I have seen this quite a few times over the years, and it has almost always been a low fluid level condtion. You are picking up air. Try adding a 1/2-3/4 quart (no matter what your dipstick now reads) and see what happens. If it solves this, remark your dipstick with the new "correct" level.