Help! Transmission Trouble

ShadowJ · May 18, 2004

I have a 99 Silverado Extended Cab with 75,000 miles on it and I am now having transmission problems. Trouble first started a couple of weeks ago. I noticed it wasn't going into overdrive while cruising down the highway. When I came to a stop sign and accelerated again I felt it shift hard from first to second. I got home and put my code reader on it to see if I had any pending codes and sure enough I had one. Its an 1870 Transmission Component Slipping. I cleared the code and pulled the pan. Changed the filter and fluid. No luck. I changed the Vehicle Speed Sensor, No Luck!. It doesn't do it all the time. I can go 100 miles with no trouble. Work 8 hours and drive home 100 miles and half way back it will fail again. And other days it will work fine all day. Anybody have a clue what it could be? I don't want to just randomly throw money at this tranny if it will be better to just bite the bullet and replace it. My wife won't like it if I have to start using the Corvette as my work truck. Thanks For the help everyone!!!!

MN Z-71 · May 18, 2004

This generally happens as a result of a worn valve body. Being that you are out of warranty I would not take it to the dealer...they will only try to sell you a reman transmission. This is not necessary.

Find a reputable small transmission shop and tell them your problem along with the code number. Tell them you know it is the valve body that is worn so you want it fixed. I would also recommend having them install a TransGo shift kit at the same time. If the shop is good they will know how to set it up properly, but dont let them firm it up to the max. Somewhere in the middle is where you want to be.

Parts and labor at a reasonable shop should be in the $400-$500 range with the shift kit. $350-$400 without.

Until you can get it fixed I would advise not driving it very much, and if you do put in 3 instead of D. This will lock out the OD and should eliminate some of the potential for slippage.

Hope this helps you out.

TarheelZ · May 18, 2004

I agree with MN Z-71 100%...good advice.

Also, GO VIKES!!!

ShadowJ · May 19, 2004

Thanks MN Z-71 I really appreciate the info. I have looked into the Trans Go shift kit and was wondering if it is a valve body rebuild kit in itself or do I need to have the valve body rebuilt and then install the shift kit? I am wanting to do the work myself and save the money. Besides the Trans Go requires the ECU to be reprogramed and I can purchase a Preditor for that and have the ability to change other performance options as well. But the programmer costs 400 bucks by itself. Again, thanks for your help!!

TarheelZ · May 19, 2004

Hopefully, MN Z-71 will chime in with your answer since you asked him, but I also have the trans-go shift in my '00 Sierra, I thought I'd reply as well.

While the shift kit does include some valve-body upgrade components, it alone will not resolve your original problem. If you want to do the shift kit install yourself, I think you'll need to have the work done on the valve-body first, and then install the shift kit.

Also, I'm wondering why you say the ECM will have to be reprogrammed. This was not required when I had my trans-go kit installed.

ShadowJ · May 19, 2004

Looking at the web site at KDSPerformance they state that on some newer models the TransGo won't work right because of Torque Management programming of the ECU. I just didn't want to get stuck putting it in and finding out after that it won't work because of the clash. I wish they were more specific on which modles of transmission really need to be reprogramed. If you didn't need it for your 2000 and it probably has the 4L60E also, then chances are I won't need it either.

Thanks a Bunch!

ShadowJ · May 19, 2004

I just went to GMPartsDirect.com and I can get a Valve Body complete for 245 plus 50 dollar core and just swap it out. First I will install the TransGo. Looks like I can get it all done for under 450 by doing it myself.