Yes, the exhaust is clear of the floor. I may try and improve clearance but I guess the exhaust would act the same in other gears, which is not the case. It really hapens only when I'm in fifth. I'm trying to determine if there iss something wrong with the fifth (though I don't see how pinions would create such a noise pattern) or a combination of harmonics that happen there. That trans is used on all W108/109/104 107s and I never heared of such problem.

Another thing is that I got all the sound deadening out of the car, first because it was crumbling into pieces, and then for the weight. So it may amplify the problem. I can work on sound deadening though I would really prefer sorting the source of the problem.