Honda Repair: Grinding in 96 Accord manual trans, exhaust gasket, noticeable change

Question
I have a '96 Accord LX with about 80,000 miles.  After the car has been running for about 15 minutes, I begin to here a grinding, almost like chains shaking, under the car as I rev up from about 2,000 to 2,500 rpms in 1st - 3rd gears.  It isn't very loud, but is more noticeable going up hill.  If I shift after 3,500 rpms, the next gear starts at above 2,500 and I avoid the grinding.  There is no noticeable change in performance or any indication that anything is wrong besides the noise.

Answer
Steve, it sounds like an exhaust shield is loose or a deteriorated exhaust gasket(s) which is on intermediate pipe between the front pipe and the catalytic. If you tuck under the car and tap on the exhaust more near the front you'll hear the rattle probably at the catalytic converter or front pipe if it's the shield. You can either remove the shield or order and replace it. If its not that let me know, RICK