Hello everyone- Excellent group.

Guys, recently i bought a honda accord 92 lx coupe from a lady. this
car has approx 50K miles on it. the first thing i did was take it to
jiffy lube; got all the fluids replaced and changed the oil, did a mini
tuneup- then i took it to carx, got all the brakes, spark pluges
everything checked- no problems were found except for the drive shaft.
the guy recommended that i change it so i did. in any case-

after this during the "pick-up" or acceleration i feel a distinct but
noticeable vibration through out the car. acceleration itself is very
swift and i can see the engine really pull the car forward. the car
doesn't hesitate, the rpms don't fluctuate, and at high speeds, 80+ i
can sense the vibration as well. now during the acceleration the
vibration is felt thru the steering. so i took the car back to carx,
they did another check of everything, ball bearings, drive shaft,
brakes, belts, they still could not find any problems with the car- and
mechanic just told me to keep on driving it. i have my reservations
because i don't think a car with these low miles and otherwise "good"
condition should vibrate like this during acceleration or high speed.
but, since carx are not "honda specialists" i know that they could not
possibly know the details of how the car was assembled.

So my question is what possibly could be the reason of vibration, the
only things that come to mind are wheel balancing (maybe they are out
of balance) or (wheel alignment) that could be bad. But when going down
a straight path, the car never really pulls in either direction- so
alignment could not be bad? But since they did work on the drive shaft
do you think it could be out of sync? Or wheels could possibly need
balancing?

any help in this matter is greatly appreciated.