I had to have engine and trans removed because of trans pressure pushing
on the back of crank and wearing a grove on the thrust bearing on the
crank, replaced the rod and main bearings along with new oil pump. the
crank was welded and reground and engine rebuilt along with a complete
trans overhaul. Got car back and had a vibration and a roar at 40 to 55
mph, replaced the rear trans yoke ,carrier bearing and carrier bearing
support. Got rid of the vibration but not the roar. Any ideas on what could
be causing the roar, trans guy says it not the trans. Did not have this before
work. Trans guy thinks its the engine mounts? Going to talk to the garage
who did the engine work and install. So what do you guys think?
SID

 

Could have someone lost a needle bearing out of the drive line u- joints? that can cause a rumble while driving sometimes quits when you let off on the throttle...Just a thought from afar...Tedd

 

NO the u joints are just fine.

 

It could be the motor mounts. My car was making a lot of strange noises before I replaced them.
Rick

 

Is the rear end OK? Could there be any issue there due to the same pressure put on the crank?

Mark

 

Just a update jacked the rear end up and put on jack stands so rear wheels were off ground, ran car up to 70 mph and had no noise up to 70 or back to zero. With car shut off and trans in neutral turned the rear wheels and no bearing noise, I swear this has me stumped. Took car out for a test and where the roar starts at 40mpg put trans in neutral and let off still had roar. So where do I go from here?


SID

 

tires?

 

Front wheel bearings?

 

X2 on this one. Tires would be my second guess.

 

Just a guess but I'm thinking u-joints. Does that car have a 2 piece driveshaft? If so could the 2 shafts be out of phase? My friend has a 63 Riviera w/2 piece driveshaft and they have to be in phase or it will vibrate/ roar. Or maybe the driveshaft angle is off?? I would guess it has to do with the latest work that was done- not tires, etc. Good luck..