Buggy 4l60e: Shiftingto Early

[vortecyota]

^ you have 15" wheels. A tuner needs to know your tire circumference, diameter or metric. Send your PCM to Nelson Performance and forget about it. IMHO.

[Mickeymotormount]

Agree with the above statements. Your PCM has to be flashed for your tire size circumference, rear axle ratio, transmission type,(60 or 80E) and any other information that can help. I had my PCM flashed to remove VATS, and also to run the 60E that I have. I gave every bit of info I could find to Brendon to flash the PCM. I have no issues. Trans shifts well and on time.

[88blazerboy]

Brief Update: I had my PCM flashed. He confirmed that the rear tire size was off by quite a bit, but he still couldn't fix the transmission stack shifting issue. He put my truck on the dyno and the transmission shifted perfect, but when he drive it, it did its usual act. This guy specializes in custom everything and building race cars. He knocked a nice chunk off the bill because he couldn't figure out what was going on with the transmission issue.

Basically, at a stop, if I floor it, it shifts perfect through the gears. If I accelerate normally, then it stack shifts pretty early, and when I floor it then, it doesn't downshift and pick-up and go - it just gradually accelerates. Would the vss signal cause an issue like this if it's not giving the right signals. The dyno did determine that my truck speedometer is five miles slower than it actually says, and my speedo is reading from the transfer case. I'm still not sure what to try. It would be really nice if i can get the transmission to work properly.

[ibelonginprison]

Brief Update: I had my PCM flashed. He confirmed that the rear tire size was off by quite a bit, but he still couldn't fix the transmission stack shifting issue. He put my truck on the dyno and the transmission shifted perfect, but when he drive it, it did its usual act. This guy specializes in custom everything and building race cars. He knocked a nice chunk off the bill because he couldn't figure out what was going on with the transmission issue.

Basically, at a stop, if I floor it, it shifts perfect through the gears. If I accelerate normally, then it stack shifts pretty early, and when I floor it then, it doesn't downshift and pick-up and go - it just gradually accelerates. Would the vss signal cause an issue like this if it's not giving the right signals. The dyno did determine that my truck speedometer is five miles slower than it actually says, and my speedo is reading from the transfer case. I'm still not sure what to try. It would be really nice if i can get the transmission to work properly.

My gauge cluster is all out of whack. Tach reads low, speedo reads low, temp gauge reads negative until it warms up, and then I think it probably reads a little high. The oil pressure reads in vacuum and the volt meter reads about 50 volts - but I can't say for certain that they're hooked up. I at least know the temp gauge/sensor is hooked up.

My shift points were always a touch funky as well, and downshift points were waaaaaay too high if I stabbed the throttle (it would try to drop to first gear at an RPM that was unsafe if I floored it) and I always wondered if the gauge cluster had any type of affect on that or not.

I'm considering just changing my gauge cluster entirely before I finish the swap. Or at least buying a different one to have on hand if I don't like how the original cluster is operating after the swap is complete.