I have a carbureted 1987 Accord 5 speed manual with all oem parts. Sometimes when I'm pushing the accelerator or when I go over dips (ie, when the suspension is fully compressed and I'm moving), it vibrates in a way that feels like I'm driving over some nonexistant roughness in the road. It isn't so much of a noise, but if feels like something is clicking or catching somewhere between the road and the transmission (the vibration is dependent on the speed of the car, not the tach). It will stop if I stop pushing the accelerator, but if I let it go for too long it will disengage for me, as I found out the other day while traveling at 70mph down the highway. It re-engages if I take it out of gear and put it back in. This occurs on all road conditions. Most recently it occured on a dry day on a non-inclined surface.

I have replaced both front axles and boot assemblies recently. My gut feeling is that it is either something in the clutch (dirt in the clutch plates maybe?) or else the transmission/transaxle, which has me quaking a bit. I think there may also be a problem with the bearings, but I think my mechanic would have picked up on that already. Has anyone else ever experienced this?