no idea was done before i got it, I have record - they used shift kit- about 5-6 k on it. before engine rebuild fine after kick down problem
I don't know if others agree, but what you describe sounds like the typical problem that arises with these transmissions. The transmission flares when trying to shift from first to second and when trying to shift into overdrive. Much of the time it won't go into overdrive at all.
This is caused by fluid leaking around the servo bores where they have become worn. The transmission case is aluminum and the servos wear down the bores over time allowing pressurized fluid to leak around them. For this reason, more pressure is required to trigger a shift and there is a flare (revving of the engine) to get enough RPM to build the necessary pressure. This just gets worse over time until it's repaired.
The Typical repair is to hone out the bores and sleeve them with
aluminum or
brass sleeves (these are examples and not necessarily the correct parts for you truck). This "should" have been done as part of any 5R55N, 5R55W, or 5R55S transmission rebuild. It's hard to imagine that any rebuild shop would skip this for this particllar transmission, but you might see if you can verify that one way or the other. A rebuild around here costs about $3500, so it's also hard to imagine what they spend $5000-$6000 on if I understand your post correctly.
There is a less expensive fix using
servos with a large O-ring that, in theory, can seal the worn gap. These fixes are analogous to what you would do for a worn engine piston bore that was loosing compression. You would either hone out the bore and install a repair sleeve, or switch to oversized piston rings.
If this was not fixed during the rebuild then the rebuild shop didn't know what they were doing. If that is what happened then you may want to try the O-ring fix as it will be allot less expensive then going back in and doing the sleeveing an can, again in theory, be done in the driveway.
LMHmedchem
