The situation: Our 4-speed gearbox was rebuilt a couple of years ago by someone with 40 years of experience on British car transmissions, but the car itself was in such bad condition that the restoration only got finished a week or two ago, so we could start driving it again. At first it was crunching and grinding quite a bit, unpredictably on up- or down-shifting in any of the gears, until the (new) clutch was re-bled. That sorted out a lot of the problems. Now, though, it rarely shifts cleanly from 3rd to 4th, often there's a noticeable crunch, and occasionally it's an outright noisy unpleasant grind. No problems downshifting back to 3rd. I've noticed that there's a constant growling when the car's in 1st gear too, and there's a very slight crunch when downshifting from 2nd unless the car is at a dead stop. So: Bad synchro on 4th gear? Residual clutch issues? Something else? There's a small amount of oil dripping from the vicinity of the shifter mechanism, if that means anything. And before installing the transmission into the car, and just afterward too, there was significant oil leakage out the tail end but the shop sorted that out - don't ask me how, I wasn't there and wouldn't have understood anyway. We're trying to decide whether there's anything we can do that might help the 4th gear grinding without just pulling it and having it torn down again. We drained the fluid from the gearbox and noticed a few metal particles on the drain plug but the fluid itself looked new, which it was. Refilled with GL4 but thinking about trying GM/Pennzoil Synchromesh to see if that helps at all. Any thoughts or suggestions would be welcome - or if anybody has a spare "known good" 4-speed gearbox lying around...
- Steve Richardson
St Louis MO
76 TR7 (original owner)
- Steve Richardson
St Louis MO
76 TR7 (original owner)