Ok,

Well, I know my transmission is not in best shape, but I have to have it last for at least a month or two before I can afford another one.

I hear a clunk going form 2-3 going very slowly and letting off the throttle. I actually won't be on the throttle and it would shift with a noticeable clunk. I had this before, but it wasn't as bad as it is now. Of corse I had a shift kit put in it, so I understand that the shifts would be firmer, but this is annoying and worries me.

The 2-3 shift is fine part throttle or higher, although if I am fully on it than it does flare up. Not much, but its there.

I took the pan off and found some sludge on the magnet, not too much, but it still was there. Pan, otherwise was clean as it can get.

MY TV cable is not adjusting itself so I am going with the best setting I feel would work.

Any suggestions?

 

My 1991 Z28 has had the 2-3 clunk since the day I purchased it brand new!
It is usually at part (light) throttle. Looooooong story...took it to the dealership I bought it from(Scot Irvin Chev in Valencia)..service advisor drives it, says "something is wrong". They take the car in, replace the ring and pinion TWICE, open up the trans....find "nothing wrong" and call me to pick up the car. I drive it home, nothing has changed, I call the dealer, they direct me to Chevrolet Tech Service Line, they tell me nothing is wrong (in other words, "go pound sand, we're not going waste our time on your car, just send in the payments"). This went on for YEARS. Took the car to my local dealership, Rally Chevrolet. Service advisor drives it, says "something is wrong".They take the car in. They run the VIN, find out Tech Service Line has told me "tough ****", and tell me to come pick up my car. I say "You said something is wrong!!, so f'n fix it!!" They change the ring and pinion TWICE, (mis)adjust the TV cable so that so that the shifts are so soft I know it would burn up in a month(!!!), do a process called "foaming the driveshaft" where, per a service bulletin directed at eliminating driveline clunks, they drill a hole in the driveshaft and inject it with a liquid that expands into foam ( I swear its true, I am still running the same driveshaft, has a rubber plug to fill the drilled hole, I have a copy of the service bulletin..!) and tell me the car is ready.... (Still with me?) I bring it back, SHOW THEM how to properly set the TV cable (it's NOT an adjustment, it's a SETTING...) tell the service manager he's a ------- idiot, and blaze the tires out of the parking lot. ......About 5 years later, I take the car to Mike's Transmission (high perf trans place). Tell him it clunks on the 2-3. He drives it, says (you guessed it) "something is wrong". He puts in a Kevlar band, 9 disc 3-4 clutch pack, a shift kit (which it already had), tells me "Come and get the car". I go for a test drive with him driving, and I see him back off the throttle on the 2-3 shift.....I tell him "Don't back off the throttle on the 2-3 shift".....clunk is still there! He bills me $550, tells me drive it for a week. I let the car SIT for a week....call him, tell him "It still clunks", although otherwise the tranny operates better than ever (which it did, and still does 8 years later....'cept for the clunk...)...I go to his shop, he refunds me every red cent!........In 1997 I bought an Astro van....700R4 (basically) trans.... it clunks on the 2-3......! (LOOOOONG STORY, HUH?) ....I think when the 2-4 band releases and the 3-4 clutch is not fully applied, this trans thinks it is in first gear for a split second, which is what causes the clunk (Dana, what do you think about that theory?). I really like the trans, the clunk only happens at light throttle, shifts good at full throttle (sometimes a have back off the gas to get it to 2-3 shift, though...!!); I think the 2-3 clunk is a design flaw, but GM will never admit it! I've messed with the 2-3 accumulator (I think theres a 2-3 accumulator) a bunch of times, called B&M, called Transgo, called my minister, called my mommy, drank way too much way too many times, had many sleepless nights...finally learned to live with the 2-3 clunk. Do all 700r4's do it? And by the way "annoying" is not the term, it flat pisses you (me) off.
Bill

 

You are right on, on the band and 3rd gear not shifting in unison. They overlap. It has something to do with one of the checkballs that need to be taken out and that part needs to be covered. I've read extensive articles on this, and what people did to remedy this. It sounds like a lot to do just to make the shift better. The thing is, your tranny still works after so many years. I have had the clunk for a year, and the shift kit just emphasised it.

 

Yes, I put a shift kit in when the car had about 2K miles on it, the dealers picked it right off because it had a non-stock pan gasket (I installed a B&M Transpak). This trans has taken A BEATING...hundreds of full throttle starts, probably 30 passes at LACR (1/4 mile track), preceeded by a brake-stand-in-first-then-shift-to-second-while-they're-still-smokin'-burnout, lots of trips to 135 MPH. I don't "abuse" it, but it certainly gets driven in a high performance manor. Has almost 58K miles on it now. EXCEPT for the CLUNK, trans function great. I wouldn't hesitate to drive the car across country. Getting ready to have a Pro-Built Street/Strip Performance Rebuild kit installed, in preparation for AFR's, Comp XFI268....probably a Procharger.
I have never been able to find any writings on the 2-3 clunk; it's either very rare, or, people won't admit their car does it. Where did you find these articles?
Bill

 

I searched around here, and what some people were doing to fix it. Also yahoo and google are awsome. Just search 700r4 and you will find many articles about clunks and other things for the transmission.

 

Thanks, Bro!
Bill