I have a ls2 swapped z28 with a built 4l60 with a 3500 stall with full lock up(car in sig). Been having issues with wot shifting and a vibration/jerking that only occurs during full lock up.
The car is having issues shifting from 2nd - 3rd at WOT. When it was on the dyno my tuner said he thought my clutches were slipping past 5k rpm, but it still made 427/371 at the wheels. I would like to think its not slipping but I cant tell for sure.. At WOT the car will just bounce off the rev limiter until I let off some and then it shifts. I dont know if this is due to a slipping clutch or poorly set shift rmp and mph. I would like to think its in the tune, but IDK and i want to get to the bottom of it so I can run the car all out. This has been going on for a long time now but I rarely acutally put the pedal to the floor so I've just put up with it for over a year.
Tell me what you think
When I'm just cruising at a given speed with the converter in full lock up (converter locks up at about 40mph and the problem is worse at lower speeds close to 40 than it is at higher speeds) I get a vibration/jerking front to back if the car begins to slow down. It only happens when the TC is locked up, and occurs when the car begins to gradually slow down (very noticible on highway with cruise controll when I go down the slope from an overpass .It will feel like its jerking back and jumping forward slightly and I hear a chattering noise. If the TC unlocks when i begin to slow/let off the gas the vibration and noise do not happen and the car rolls smoothly.
Maybe rear end problem? My best visualization in my head of what could cause this is the there is "play" in between the teeth of the pinion and ring gear, when gas is applied they lay properly, but when the car begins to slow they may bind causing the vibration? What you think?
ALso, SOMETIMES when the converter locks up I hear a pop from the rear of the car.
I know these type of things are hard to to diagnose through my explanation but any advice or ideas are appreciated.
I'm putting on new rotors and pads today so when the rear is up I plan on checking the rear end pinion bearing, ujoints, , trans mounts, and tranny output shaft bearing/bushing... Is there anything else you guys would check out while im down there that may cause this?