I have an 86 z-28 with a LB9 motor and a 700r4 tranny. The problem I have is when I put the car in drive, It runs down the road fine, shifts through the gears smooth, etc... But if I put it 3, 2, or 1, It won't go into gear. It moves very slightly, but for the most part it seems like neutral. I changed the transmission fluid and filter (did NOT flush) and still didn't help. Does anyone think flushing it would correct this problem? When I took off the tranny pan, the used fluid was pretty black. The pan had a steel gasket on it (factory fluid??). Thanks for any help!

 

You may have a problem in your overrun clutch pack. It is only put on in manual ranges to provide engine braking. It is in the same housing the forward clutches are in. If your overrun clutch pack has a leaking seal, it may be bleeding off enough fluid to starve your forward clutches, causing a slip. If this is the case, flushing the fluid isn't going to help. Hope this helps.

 

Do you think that it'll hurt the transmission as far as keeping it in drive? Thanks.

 

I hate to say it 'will' not have a problem, but it shouldn't. As long as none of your other gears are slipping it is probably ok.