Danny S

I just bought this Purple Haze 92 z28 for $1800 because it runs good with the exception of a tranny problem. It is T-Top 5.7ltr v8 automatic all power interior.The guy I bought it from said he took it to his mechanic and he told him it was some small $60 part making it shift like it is. It takes off great but stays in first until you get it to like ridiculous rpm range and then it slams into 2nd. There is no stall converter on it and no shift kits installed. It is unmolested and original. He did a fluid flush and filter change but got the same response. Not sure but believe it is a 700r4 tranny if original.

Ok he said it is the trans shift solenoid. Is this an external/internal part that I can replace easily? Thanks.

AaronIROCZ

iTrader: (5)

Wrong forum, moved to transmission forum.

Danny S

It says it's Transmissions and Drivetrains and it's in with everyone else who has tranny issues. What did I do wrong?

RBob

iTrader: (1)

No such thing as a trans shift solenoid in the 700R4.

The issue sounds like the TV cable is either broken or disconnected. May also be wayyy out of adjustment. The TV cable controls the line pressure. And when it breaks or disconnects on the newer 700R4s there is a check ball that forces maximum line pressure.

So the trans won't shift until high RPM.

The TV cable goes from the throttle lever on the TB to the right front side of the transmission.

RBob.

Danny S

Okay thanks. Will check it out for sure. Could be an easier and cheaper fix than I originally thought. That would be awesome! Thanks RBob!

Danny S

Well I checked my TV cable and it has no slack when in full throttle and is connected at both ends. Also I think I made a mistake on identifying the type of tranny I have. If I'm not mistaken now I believe I remember reading that the ONLY difference between the 700r4 and 4l60 is overdrive, correct? Well when I got into the car I noticed my shift plate (that is original) has OD on it. So my question is I have a 460l?
So I'm back to square one. Anyone got some ideas for me. Maybe it's the shift solenoid the previous owner told me about? Thanks.

'84thunder

no buddy, u have a 700r4. my shift plate says 1,2,D,O/D as well. i have had the same issues as you when i got mine. shop identified a hydraulic problem internally in the tranny.

if you know how to fix a tranny like that, go for it. if not, make a small investment and get it fixed or get a used one.

RBob

iTrader: (1)

A 700R4 and a 4L60 are the same transmission. In the early 90s GM changed how they named the automatic transmissions. For the 4L60 the 4 is for four gears/speeds, L for longitudinal (T for transverse, FWD stuff), the 60 is the torque rating, IIRC in metric.

If there is an E on the end: 4L60E, it is an electronically controlled transmission. No factory stock 3rd gen has an E transmission. Although many do now.

Danny S: thought of another idea, the TV valve may be stuck. This too will cause a high line pressure. I've read here that snapping the TV cable open/shut (so to speak) rapidly usually frees up the TV valve.

I don't recall whether to do this with the engine running or off.

RBob.

AaronIROCZ

iTrader: (5)

You orginally posted in the TPI forum, I just posted that it was in the wrong forum so you would know why it was moved.

Seafarer12

Where is the adjustment on the tv cable? Like it has been said I would unhook it and pull it in and out a few times to make sure the valve was free (you can feel the valve move in the cable) then I would move the adjustment in (so it pulls the cable less) if it is all the way out. How many miles are on it and what does your fluid look?