Hello and thank you for trusting Just Answer with your question. I'm Dj.
Can you tell me more about this vibration?
Is is something that you feel and hear, or do you just feel it?
Does it come through the floor or the seat, or more through the steering wheel?
Do you hear a drone sound at 70 mph?
Please let me know and we can go from there.
I can feel and hear it, sound start like humming, like you said drone sound.
It more seems like coming from floor.
When I put it on Jack stand after replacing all tires with spare, it was doing same. start exectly at 65 mph.
I notice Transmission oil level high. I am planing to drain to level tomorrow. It is almost 3/4" above high level.
If you can hear it, it's a driveline problem, not a tire or wheel problem. At 70 mph, you tires would be rotating at about 9 revolutions per second. So it you would have a 9 hertz sound. That's below the ability of humans to detect.
At the same speed, the engine, transmission and driveshaft would be turning at 33 hertz. That is a sound that you can hear and feel.
You stated that changing gears doesn't change the sound, only vehicle speed changes the sound. That narrows it to the driveshaft, or flange on the differential being out of round.
Put the vehicle in the air and support the rear axle so the driveshaft is as straight as possible. Then put the vehicle in gear at about 10 mph. Check the driveshaft for any wabble our out of round.
It it spins straight, then the problem is likely that the driveshaft is out of balance. If it doesn't spin straight, it't bent or was built out of round and it will never balance.
Whole drive train is balanced, with replacement of 2 u joints.
I have put rear on two Jack Stand, turn off Traction Control and spin it at 65mph, it looks perfect.
still noise and vibration starts at 65mph
Tomorrow you were planning on taking it off and trying it. That's still a good plan.
I haven't heard anything to convince me that the problem isn't the driveshaft. I understand that you paid money to have joints and a balance done, but there aren't that many parts on a car that can cause the vibration that you describe.
The driveshaft has the mass and the rotational speed that are both necessary to cause a vibration of this magnitute and frequency.
So let me know what you find tomorrow and we'll go from there.
Thats what my understanding was and thats why I was ready to spend this kind of money.
Make certain that you support the axle on jackstands or you won't get accurate results.
It was done by http://www.americandrivetrainrepair.com/
I will disconnect shaft from u joint at Transmission.
OK, let me know.
Did you send the same sentence twice? That's what it looks like on my screen, sort of.
No problem. I made a mistake once.