Vibration on acceleration

Try having the front wheels balanced and tracked .

Have your wheels balanced while on vehicle. Not all places do it but worth it as could even be a weight missing from a drive shaft ?

were the motor & trans mounts checked?

Rob, assuming this is a 4X4? Sounds like a bearing. They can vibrate, snap, clunk, all kinds of terrible noises or vibrations.
Axle u joints will also do this. Is it all wheel drive?

best guess is to have the CV joints checked, make sure that the boots are good in the outside joints. but it could also be the inside joint just has to much wear. you are at the right mileage for either to be the problem, the next time you get the vibration put a little pressure on the steering wheel in one direction then the other and see if the vibration goes away if it does suspect the CV joints. and don't just replace the outside joint replace both half shafts. if the vibration does not change or go away when you put pressure on the steering wheel then suspect lower ball joints.

Rev the engine while out of gear , if vibration check units driven by fan belts. if no vibration and is front wheel drive, check joints on both drive shafts, if rear wheel drive check front and rear tail shaft u / joints, check wheel balance or out of round tyre .

if what your feeling is not an engine miss,
then it will be a motor mount,best chances are the front center one,,
or top trans mount

check the motor motor mounts for movement,
watch how far engine rocks forward or back with it running and foot on brake

check serpentine belt tenssioner

Me too i think it a cv joint problem a cv joint got 3 rond bearing when turning each rond ball goes in a chanel it spin in there sometime that chanel get damaged a little hole appear and in occasion the ball get stuck in that hole and that your bad vibration i gave you example