GXP transmission rebuild

[gxp-hawkeye]

Got a P-0741 code on the Bonne and am getting the trans rebuilt next week. Was wondering you boy's thoughts on switching the gear ration from stock 3.71:1 down to the 3.29:1 the t-80 has on some of the Caddy's out there?

[01bonneSC]

You WILL NOT accelerate nearly as quickly. And you will have to get the PCM tuned for the new ratio, I would imagine.

[00Beast]

The 4T80E only has 2 ratios, 3.11:1 and 3.71:1. You would have to find a good gearset, and you'd have to find a way to get the PCM tuned to accommodate the changed gears...

[gxp-hawkeye]

Couldn't remember if it was 3.11 or 3.29. I figured there'd be more to it than just an easy swap, there usually is. I was at home thinkin bout it and the thought crossed my mind

[94SilverSSEi]

But on the upside, you should get slightly better gas mileage with the different gears.

But I'd take better acceleration over a very slight increase in gas mileage any day.

[gxp-hawkeye]

gonna stick with the stock gearing prolly, can't blame a guy for random thoughts though. just wish there was more/anything you could do to a gxp.

[Loopy]

Just curious as to how many miles are on your GXP.

[gxp-hawkeye]

68k young, I'm the second owner. Has a fair amount of wear on the TC button which I take as some jackass before me loving to abuse the *shoot* out of nice things. No worries she's taken care of now

[CMNTMXR57]

Wait, time out here. Why are they rebuilding the transmission for this code?

This is a TCC solenoid code. I believe this one is when the PCM commands the TCC on, if it detects a high amount of slip in gears 2, 3, or 4, for something like 5 seconds or more, this code is set.

I belive this asks for checking of fluid. Then following a certain set of driving instructions, in 4th gear, at operating temp, and monitor the TCC. It has to come on for 5 seconds and asks you to monitor slip speeds. IF all checks out, and the slip speeds are within spec (this would have to be looked up), I would look for a pinched, plugged, or twisted line to the radiator as it may be putting the transmission in hot mode.

If none of that works out, then you move on to checking the TCC control valve, regulator valve, feed valve or enabling valve when commanding the TCC on.

If there is some slip speed, but not within the spec looked up, check that the TCC Pulse Width Modulator screen isn't plugged, or that it's o-ring isn't leaking or cut. If thsoe all check out, then we move on to the internals of the transmission. But even still it's not a rebuild. It's replacing the case cover/shaft seal and/or case cover to drive sprocket and possibly drive sprocket support are worn.

Moving on, you'd remove the Torque converter and oil pump shaft and look at the drive sprocket, driven sprocket and drive link. The final spot to look is the Torque converter viscus clutch.

No where in that is a complete trans rebuild. Is there something you may have left out that you're not telling us?