Sorry folksI was in the wrong forumwith my 1st post. Have a 99 Blazer LT, V-6, Auto-4wd., 160 K, bought it a month ago. Problem: on a random basis at speeds below 60kph the "powertrain" seems to 'disconnect'and the engine revs up ( similar to shifting into neutral). If I momentarilyrelease theaccelerator and then push it down again I can feel the reconection to the power train. It appears to shift normally all the time so I'm not sure where to look. Highway cruising is not a problem. It's my 1st 4wd vehicle and with 35 yrs as a mechanic way behind me I would like to be able to talk inteligently to the new generation tranny repair guys. I'm guessing a possible torque converter problem or maybe a speed sensor? Any help would be appreciated.
Wrench

 

Hey Wrench, How does the fluid look? I had a 2000 Blazer in my bay the other day that acted the same way and it was low on fluid. HTH Korey.

 

I havechanged the fluid and filter. Not being the original owner makes the maintenance record sketchy so I also had the fluid in the frontdiff changed. The rear diff and transfer case samples look ok.

 

Not doubting your abilities, just wnat to cover the bases here.
Check the tranny fluid level after 20 minutes of driving, on flat level ground and with the engine running.
If the fluid check out OK. I think your Troque converter diagnosis is right on. When you talk to someone at the tranny shop, get an old guy. They will no doubt speak your language.

 

Hey I'm back. Took it to a tranny shop and there were no codes, tranny is clean inside. The TCC has been fixed, shift solenoid replaced as well as every other electrical device in/on the tranny BUT it still has the problem The only additional info I can pass on is that the problem occurs after warm up, after deceleration at anything below 60 kph and it appears that the tranny does not downshift so when you accelerate it is in a higher gear giving the impression of slippage until it finds a lower gear. Its a pain to drive in traffic! Any help is most appreciated.
Wrench

 

Did the trtanny shop cehck the governor? Did they give it thier seal of approval as in there is nothign wrong with the tranny?

If so, your problem lies in teh engine or puter.

 

Did the tech at the tranny shop road test it with you and did the problem occur during the test?
Just from what I've read so far, I would think that there is a problem with the 3-2 shift valve assembly either shorted or damaged, damaged seal or the check ball is not seating.
If the tranny shop can't find the problem, I'd take it to the dealer.