2001 Tahoe shifting hard

[NJTahoe]

Let m explain everything that is going on. I picked up a used Tahoe this past weekend from a friend of a friend.
There is no heat in the Tahoe and I looked at it and it was low, and nasty looking. I added some but still nothing so I thought it could use a flush and I had that done and still the heat isn't working. Yesterday while I was driving home, I had to slow down on the highway and it started slamming into gear. Now I'm freaking out because I just sold my old car and I don't have another vehicle. Transmission fluid was a little higher than it should be and there were bubbles on the tranny dip stick. I've been looking all over the internet for answers and haven't seem to find anything conclusive online except go to a shop and have them look at it. Which kinda sucks because I don't have time to do that. At least not for 2 weeks and I am worried about driving it that long without knowing what the real problem is. I did get an O2 sensor code the other day and I reset the codes and I was going to put one in yesterday but I don't have the right tools to take the old one off. Need to stop by Pepboys today after work to pick up the right tools.

I did find this article about the transmission problem I'm having..

http://www.drivetrain.com/parts_catalog/transmissions_automatics/gm_4l60e_overhaul_kit.html

Problem
Shifts into gear harshly, car feels sluggish off the line, No 1st, 4th or Torque Converter Control (TCC) lockup available, Manual 2nd, 3rd and Reverse are only available gears, CEL is on

Symptoms
Transmissionmision is either in limp-home mode or has lost electrical power. If there are lots of error codes in the PCM, check the underhood fuse that powers the Transmissionmission, and if it pops again, look for a short in that circuit like an O2 sensor harness touching exhaust. Otherwise, check PCM codes for a particular fault in the Transmissionmission causing the PCM to put it in limp-home mode.

Possible repair
check the underhood fuse that powers the Transmission



Any other advice would be greatly appreciated!

 

[NJTahoe]

Ok so I after spraying some PB Blaster I got the old O2 off and installed the new one. Transmission is still shifting hard when i'm light on the gas. When I step on it, it shifts pretty good. After speaking with my friend who sold me the truck, I realized that when I reset the O2 code the other day, there was a warning and it said that it would reset the ECU and the vehicle would drive poorly for a short period. I haven't really driven the Tahoe more than 20 min, thats how far from work I am, and I think I just need to fill up the tank and just drive to have the Tranny Relearn. I also had to relearn the Passkey because the Anti Theft was kicking in and shutting down the vehicle. After a quick key relearn this morning, I was off to work. I will post again once in a couple of days if everything works out.

 

[NJTahoe]

This harsh shifting that was happening started this past Wednesday, 4 days ago after I reset an O2 code using a USB OBD II and my laptop. It reset the ECU and I believe the transmission PCM. I haven't been driving long distances, maybe 10-15 miles to work and back so I haven't been letting the ECU and PCM relearn all of the information it needs. Last night after work I drove up to NYC to see a friend of mine who is a mechanic to talk about another problem I'm having with the heat. We are going to flush out the heater core sunday and probably the whole cooling system and put all fresh dexcool. The Hoe kept shifting harsh and after getting home and parking, I figured I would take it to AAMCO and see if they could find anything out. Just as I got in and put it in drive, I was waiting to be jerked into 2nd gear but it DIDNT!! woohoo!! After a 2 hour drive and a nights rest I can't even feel the shift anymore, it's so smooth again!! Now maybe I am a bit premature about this but I'm stoked right now. I didn't even bring it to the shop I drove it around for a little and stopped and started again to make sure it wasn't a fluke, but right now It's great!
On the way: coolant flush, new tires, alignment and plugs.

 

[rawlz]

I am having that same problem where it shifts a little rough when i am soft on the gas. When I'm hard on it, it shifts fine. It sounds like your fix for it was to just drive. I just came back from a road 700 mile road trip, so I dont know if I will have the same luck.

Would you think its the throttle position sensor?

 

[NJTahoe]

I am having that same problem where it shifts a little rough when i am soft on the gas. When I'm hard on it, it shifts fine. It sounds like your fix for it was to just drive. I just came back from a road 700 mile road trip, so I dont know if I will have the same luck.

Would you think its the throttle position sensor?

Well it's been a while since I've posted on this and the problem still isn't fixed. I went to a friend of a friend who has a transmission shop and he replaced the Valve body with a used one and that seemed to resolve my harsh shifting issues temporarily. Right now it seems to be runing good for the first 30 min of driving, but once it gets warm it seems to be overheating and shifting hard. A while back when researching fixes for this I ran across an updated valve body that I should have ordered when I saw the part # but for the life of me, I can't seem to find it again.

If anyone knows the part # for the update Valve Body please let me know.

 

[thompsoj22]

hate to say it but

find another forum, there are only "zombies" here who lurk but dont answer. good luck.:superhack:

 

[NJTahoe]

find another forum, there are only "zombies" here who lurk but dont answer. good luck.:superhack:

It wasn't bad when I first joined. But maybe you are right. No one is here anymore and if they are, they don't want to help

 

[thompsoj22]

try GMtruckclub.com

It wasn't bad when I first joined. But maybe you are right. No one is here anymore and if they are, they don't want to help

i cant live without forums because i do all my own maintanance. jeepforum.com, MBworld.com, both are fantastic. try GMtruckclub.com, i just joined and it seems to have more members who are active. good luck, that trans is a $1300 3yr warranty on ebay. dont throw to many dollars at yours only to concede to a new unit.

 

[samotahoe]

how are the engine mounts?

 

[NJTahoe]

Tansmission is working fine, Engine mounts are good, the problem is still the Valve body. When I take a long trip it starts to shift hard, but I believe its just a faulty valve body.
I need to get the new Valve Body with upgraded parts, but I can't seem to find it anywhere.

 

[samotahoe]

your probably going to have to hit up a trans shop to get it, they might have a vendor that they can get it from but will charge you for the resale on it