i had a similair problem its actually the motor mount has been broken or the rubber grommets holding the exhaust in place are getting worn down and need to be replaced!!
Your transmission will slip and clunk or bang when changing gears, can have trouble changing thru the rand of gears, ans will eventually over heat and burn out.
You're a clunk-head...
I'm going to assume its an automatic transmission. Is the millage higher than 50,000? If so try changing the transmission fluid.
Some could be's, Bad u-joints in driveshaft, Bad transmission mount. Transmission cross member loose.
Vrrrrrrroommm If the driver puts his foot down. Brrrr-clunk-rrrrr-clunk-rrrrrrrrr With added gear changes.
A centipede with a wooden leg
It shouldn't ...
If the clunk is most noticeable at takeoff or when coming to a stop, the u-joints on the drive shaft probably need to be replaced.
You may have U-Joint problems
The cast of Clunk-Click - 1973 includes: Gary Glitter as himself Jimmy Savile as Himself - Host Chicory Tip as Themselves
U joint
Don't switch on the fly, that's just stupid. You'll need a whole system overhaul.