5 spd manual - engine pulls strong around town - all rpms - after about 15 minutes of driving - when everything is warmed up well - when passing or climbing hills at freeway speeds - there is a loud chassis thumping -
the frequency will change with speed - but does not change with downshift/engine RPM changes - any clues -
I was thinking a CV joint, but there is no clicking when turned hard, either direction - maybe symptoms vary

thanks in advance for any help