91sbc5speed

I just picked up a 95 z28, anyway it has tranny issues. First of all never has 3rd or4th. I can can get 1st and 2nd in drive. But when I manually shift to 1st it works fine but when I manually shift to 2nd acts like its in neutral at all times. The speedo also reads like 20 mph high. I know it needs rebuilt, but does anyone have any ideas what I wrong?

mrvedit

The reason no one has answered is that this question has been asked hundreds of times, at least twice in just the last week, and the answer is easy to find with a Search.
E.g.:

https://ls1tech.com/forums/automatic...gear-gone.html

The answer is always the same - the 3/4 clutch has failed and you need a rebuild.

IMHO, I would skip rebuilding that trans and get a slighter newer rebuilt one. The '95 is an oddball, kind of like a beta-test for the PWM solenoids. Many parts including the valve body are unique to that year and far from the best. The '95 also had weak internals and is probably one reason the 4L60E has such a bad reputation. The '96 straighten out the valve body problems, the '98 started to strengthen internal parts for the LS1 engine; the '01 and '03 are stronger yet. Just my opinion anyway.

91sbc5speed

Thanks, so can I use any 95 and up non ls based 4l60e in the z28 with no issues.

mrvedit

Things changed in 1998 when the "Big Bell" housing came out; this has the hole in the 12'O'clock position and also uses a 300mm input shaft and a different sized torque converter which won't fit your car without expensive custom parts.

Therefore, Yes, a '96 or '97 trans for non-LS engine would be a good choice.
The real question here is whether you are looking for a junkyard trans, get a local rebuild, have it locally rebuilt or get a performance rebuild from one of the sponsors here.
For any rebuild/rebuilt, your should go with what the vendor/shop recommends.
We had a another post here several months ago and the person wanted to rebuild it themselves. To avoid surprises, the consensus was to get a '95 specific rebuild kit and the "usual" internal upgrades to strengthen it.