my darn transmission in my 84 Z always slips out of gear when its shifting into 3rd gear, i put a new filter in it that helped a little bit, but what should i do? take it to a transmission place?? or what is this common problem?

 

Sounds like the 3-4 clutch pack is toast. This is a common weak point in these, especially if pushed hard. It is time to come out. I would stick with the original trans for calibration purposes but there is upgrading that needs to be done to make it more durable.

 

what kid of upgrading, you mean the one i have or i should replace it??

 

Check the transfluid level "when hot". The fluid level must be right at the top of the full area on the stick, on these transmissions. Add an extra 1/2 quart and road test it. Part of the filter is being uncovered while accelerating. This worked for me.

 

I like to stick with the original tranny in most cases, especially if it is something like a Z-28 since you won't just stumble across another tranny that has the correct shift timing W/O a lot of hassle. That being said, the '84 needs a bunch of parts to bring it up to snuff. You could get a later unit, such as an '88 or later and use a lot of the parts from that as a starting point. There is more that I do but that will get you going. Don't forget the TransGo Reprogramming Kit and High Rev Spring Kit too.