Long story short, been chasing a high speed vibration forever. The rear is FINE and the driveshaft and joints are FINE. Wheels/tires are perfect and straight and balanced. I was wondering if there is anyway I can check this while in the car... thanks!

 

What are you trying to check for?

 

to see wtf is wrong with my transmission lol. ok here illg ive u more info.

Before my rear u joint gave out... i had this wicked vibration at 80+ MPH and it felt like my driveshaft was out of balance. The vibration was very bad in neutral or with the clutch pedal pushed in. the vibration was almost gone with the car in gear.... and i hardly felt it when I was giving the car gas while in gear.

I had my stock driveshaft balanced and put new u joints in it. also got an alum shaft out of a 2000 camaro.. had all my wheels straightened and balanced. checked everything in my rear. everything was fine.

My rear u joint gave out and set my airbags off. I replaced the windshield, put my old stock balanced driveshaft in, and the vibration is now WORSE. i cant go over 40mph without the car shaking like a death trap. SAME vibration as before. feels like driveshaft is going to fly out of the car.

I think whatever was wrong inside the transmission got worse when the rear u joint let loose and the old driveshaft pegged the ground.