Hard 1 - 2 Shift
I recently starting experiencing a very hard shift from 1st to 2nd gear in my 2000 z71. The transmission seems to hesistate and then loudly slams into 2nd gear causing the truck to shudder. It seems to occur after I have been driving for a while and occurs randomly. If I turn it off and let it set for 5 to 10 minutes the problem goes away. Any guess as to what is causing this and how to fix it?
I've heard that computer upgrades may fix the problem. Anyone have success with the upgrades? How much do the latest and greatest upgrades cost out of warranty?
Thanks for any info.
have you checked your tranny fluid levels?
Sorry, your tranny is on it's way out.
You can do a search on here for hard 1-2 shifts,
The letting the truck sit for awhile just resets the computer relieving it of it it's "max line pressure" mode for a tranny that is slipping.
Here yah go...
This sounds a lot like the problem I was having with my '02 Silverado with the 4L60E transmission. I was also told by some people that it might just need a PCM upgrade but when I took it in (still under warranty) it turned out there was a TSB on the problem. As I understand it some electrical interference was affecting a sensor for the transmission and that was causing the line pressure to fluctuate, and all it needed was simple electrical connector and rewire. I had it fixed a few weeks ago and the problem hasn't resurfaced yet so it looks like it worked.
Check this thread: http://www.fullsizechevy.com/forum/s...threadid=99441 for more on what my truck was doing. The TSB related to my issue is at the end, it says the problem is present on '01-'03 models but maybe your '00 is experiencing the same problem. If it is this problem I don't know how much it'll cost out of warranty but I can't imagine it'd be too much. Good luck.