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Rebulit tranny installed no shift tilll 2500+ rpm, Im gonna need help

Jorge6.5

Jorge6.5

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Upstate New York
Finally got tranny and converter installed along with everything else. I take the truck for a ride and it wont shift till 2500 rpm and sometime higher when shifting to over drive. So this concerns me now, did i get a too high stall converter? I believe it was around 1800 stall from what the mechanic said. My speedometer is also off now not sure what thats about but it read around 30mph when im going around 60mph.

Tranny also slams into gear like scary bad like the truck is gonna snap in half. I did have a transgo hd2 kit installed and tranny guy said it wont slam into gear but god damn is it. All other mods are in my signature.

I just spent loads of money here and nothing seems to be going close to right, please help me!
 
Sounds like a problem with the speed sensor in the tail housing if it's a 2WD, or the speed sensor in teh transfer case if it's a 4X4. Could also be a problem with the 4X4 switch making it think it is in 4 low when it is in 4 high. I doubt a converter would cause this. A converter problem would be if you had to rev it really high to just move. If this is the 96 in your sig, then check the 4X4 switch in the transfer case first to make sure it is plugged in.
 
Yep but u gotta get one of the pros to help u. They talked me thru setting mine but I am not sure urs works like mine. My truck acted just like ur saying, scary hard shifts and very reluctant to go n2 od. They will chime in, in the meantime search the stickys n tranny section n u will find info thats good reading.
 
96 doesn't have a TPS, it uses an APPS(accelerator pedal position sensor) which is the electronic throttle pedal assembly inside the truck. This issue sure sounds like a bad speed sensor or an issue with the install. You need to get it on a scanner and see what is going on. The slamming into gear sounds like either a problem with the TRANSGO install or it is in limp mode which defaults to max line pressure. Your going to have to put it on a scanner and see what is up with it.
 
Yes I'm beginning to think I have a bad speed sensor. Not sure what could go wrong in the install but you never know. And I'm not the one who rebuilt the tranny, the tranny shop has previously installed the same transgo kits on these trannys so hope all is well in that department.

What would set limp mode? The speed sensor? I'm not getting a check engine light but will it still set a code?

I've got an mt2500 snap on scanner that I'll try using if I can completely figure out how it works for tranny diagnosis

Thanks for the help guys
 
Many times trans codes will not set the check engine light. So just because it isn't on, doesn't mean there isn't a problem. And limp mode can be triggerred by any number of problems, without scanning couldn't tell you what it is.
 
Well i got the new speed sensor and and it changed nothing, speedo still wrong, very hard shift from 1st to 2nd not so hard 2nd to 3rd od takes for ever to get to and i dont think the converter is locking up.

Scanner showed no codes at least i dont think, not 100% sure on how to use these scanners.

Tomorrow im gonna go over all plugs and connections and possibly bring it to the transmission shop
 
Tghis is why I hate throwing parts at a problem, most of teh time it doesn't fix it but leaves your wallet lighter and you pissed that it still isn't fixed. You need to go in and check the wiring, make sure the sensors are hooked up to the correct plugs, and find out why your speedo is off.
 
I went over all of my work and found nothing wrong, all wires and plugs are good. connections are all clean and plugged in properly in their respective locations.

Im still getting hard shift from 1st to 2nd, 2nd to 3rd not so bad and have to be moving pretty fast to engage over drive. will shit from od to 3rd when not needed.
Wont shift till around 2500rpm
Speedo still way off. Im lost on what to do next. When time permits ill be bringing my truck to shop that rebuilt my transmission, anything I should tell them to check out?

Thanks a lot guys.
 
It sounds like the speed sensor is not picking up correctly. Did you give them the whole tranny, including the transfer case? If so, maybe they didnt line up the gear teeth on the output shaft right with the sensor, or put the wrong one in, like a 20 tooth ring instead of 40, since its reading half of what it should. I havent pulled one apart to know how that gets lined up or changed. Or if you put the transfer case on yourself then could be that you didnt get it together right.

The PCM controls shift based on pedal input and speed, so its no wonder its jacked up if the speedo is wrong because the PCM gets the same input from the VSSB module. So unless you also swapped the VSSB module or messed with its jumpers that define the gear ratio and wheel height, then must be an issue in the 4WD transfer case.
 
I brought them only the tranny and installed everything myself

I did drop the t case a little bit on the concrete right on the bottom of the tail housing but i didnt think it was that bad. I might pull the tail housing off the t case and see what i can find. other then that not sure how i could have installed the t case wrong.i have swaped t cases before but this one is the first time ive dealt with push button t case

thanks
 
Does the shaft in the tranfer case move back and forth at all when you slide it onto the tranny output shaft or push in the driveshaft? I've never dealt with one.

Check this out
http://www.rsgear.com/technical/dia...r-case-gmc-bravada-envoy-trailblazer-4x4.aspx

The VSS reluctor ring is item #4 and it has two reluctor wheel retaining rings, #5 and 26. If you dropped it maybe or maybe somehow a ring came off and the wheel is out of position.

Maybe the VSS is just picking up the grooves on the actual shaft instead of the reluctor wheel.
 
I havent pulled the tail housing yet but now im tempted to remove the whole t case, thanks for that link! im gonna study it
 
The output speed sensor from 94+ is in the transfer case, so the trans wouldn't affect the speedo. It could also be a problem with the input speed sensor, but it wouldn't affect the speedo.
 
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