Clutch Problem

[QuakeWork120]

I'm driving around my g/f's 1987 Honda Civic CRX Si because my 1997 Acura Integra GS-R got STOLEN! (I got it back, minus my emblems, my CAI, the front seats, the stereo, wheels and tires, and a few other things) Anyways, back to the CRX. It refuses to stay in 5th gear. First through fourth gears work fine. I'm driving down the freeway, going about 75. I have to let go of the gas to avoid hitting somebody in front of me and it drops out of gear.
The funny things are is that it works fine when it's cold, and it doesn't work when you are going under about 50 mph. Remember, just 5th gear. I thought maybe the sychros were going out, so I tried double clutching it. It still drops out, if I manage to get it in gear. Anybody got any ideas? The clutch was recently replaced (with a stock clutch).

[jeremy172]

it sounds like a bad sychros are bad it does not do it when its cold because the oil is thicker. My tranny used to do that i had it rebuilt.

[Ricochet]

Bad synchro. Double clutching doesn't do one damn thing on a Honda. Go to www.car-part.com and see if somebody around you has a new tranny. It should cost you $150 or so.