Exhaust Drone On 89 Gt?

[1fast302]

Looking to get some opinions on if this is an exhaust drone or not. Starts about 60 mph and gets worse with speed but goes away when I let off the gas. The " drone" sounds like a pipe is right against the floor of the car-but all clearances for the exhaust are good. The shifter also vibrates very badly at highway speeds, could this be related?

I've got:
Rebuilt T-5
3.73's
BBK 1 5/8 long tubes
BBK Off road h-pipe
10 year old 2 chamber flowmaster mufflers and tailpipes
New convertible motor mounts
Poly trans mount
Stock driveshaft

Does an exhaust drone with this setup only occur when on the gas, then disappear when coasting?

 

[jrichker]

Flowmaster and drone are synonymous - if you have one , you are going to have the other. All chambered mufflers drone, it is a fact of life.

The vibration in the shifter could be a bad rear transmission mount or a driveshaft that is out of balance. The driveshaft will also cause vibration problems if you failed to align the yellow paint marks with each other when re-installing the driveshaft.

 

[fords2live]

Mine did that a while back. All 4 bolts holding the driveshaft to the rear end were finger tight. I only noticed it on the highway, didn't do it when I got into the throttle or let out of the throttle just at constant RPMs. Grab some lock tight and check the bolts.