4t60e shift issue

[Jbrogan]

ok i have a 3.29 4t60e in my car it came with a 2.96. i have been having a problem with the shifting. it shifts at 30 50 and 60mph no matter if im flooring it or driving normal. i can run the gears out if i shift it manually. also it doesnt down shift. i kind of like the problem though because normally overdrive will not engage when yer flooring it but in this case it will so i can do about 170mph topped out. but for drivin around town i would like it to shift out of 2nd when im going 35. anyone know what casues this?: i know its somthing electrical because one time i washed the engine bay and it worked properly for about 2 min.

[gpse3400]

If you are still automatically shifting then I think it is safe to say the transmission is not ant fault. I think you have sensor issue, either the MAP, TPS or MAF. I would pull out your scan tool and see if everything is responding at it should.

[3400-95-Modified]

Have you datalogged it to see if there are any sensor issues? Sounds like it may be a bad solenoid in the VB causing the trans to go into limp mode.

[RedZMonte]

I have an uneducated question.. If your running a 3.29 in a car that came with 2.96 originally would that cause a problem? have you changed the gear ratio in the ecu? the shift points are all controled electornically as im sure your aware of and if they are not recalibrated i would assume it would shift at the wrong point... when you manually shift it you are not allowing the ecu to change the gears as it would in "D/OD" Im sure your aware of this but i thought i would ask if you have recalibrated it already, sometimes its the simple things i forget to do

S

[Jbrogan]

no i didnt recalibrate the ecu for that but it was shifting fine at one point. i changed the trani when it started messing up and it still does it. one time i washed my engine bay and it was shifting properly for a few minutes. im thinkin that it had somthing to do with it. maybe a short or somehting.

[3400-95-Modified]

For a 96 running a 3.29 it should shift fine, maybe a bit high or tap the limiter, but it should shift... not short shift. The only issue you should see if there is any, would be a trans component slip code, is your SES light on? You will get this code after driving on the highway for an extended period of time in TCC lock because the ecm will calculate your running too many RPM's after that code is thrown TCC will not lock anymore and there will be an SES light and I think that's it.

[Jbrogan]

yeah the ses lights always on yea thats prolly the problem

[3400-95-Modified]

Well for one you have a tuner, the SES light should never be on... Mine isn't and I have a lot done. Hell I don't have the second o2 installed anymore either.

And what codes do you currently have thrown?