My 1988 740 wagon has drive train roughness/rumbling at certain times. After it has warmed up I notice this around 2000 to 2500 rpm in the lower gears when accelerating. It is worse when the car is loaded. I don't notice it when cruising at constant speed. Any ideas?

 

Probably a bad u-joint?

Wait for others to responed

 

What is the best way to troubleshoot the u-joints? Thanks.

 

http://www.vcoa.org/700-900-faq/Driv...iling_U_Joints