new trans in, now the car vibrates

[crankin]

I just got this thing in and the car vibrates pretty badly between 45 -48 mph, more so on deccelaration.
On the center driveshaft bearing, I preloaded it as recommended. Could that have screwed it up and caused this type of vibration? If so, do I have to drop the exhaust again to reposition the bearing?
Or could the car have gotten out of whack in the front suspension from being up on stands?
What usually causes this type vibration? Any input is appreciated.

[crankin]

BTW, I also had 2 new front tires put on. Could balance cause this problem?

[AllGo'n'Show]

Could be tranny mounts
Could be suspension if it wasn't lifted right and bent something
Could be your front tires out of balance

Take it back to the shop and tell them it is out of balance and you have a vibration and let them help you find the problem.

[Jr ///M5]

Did you remove the drive shaft? Did you pull it apart?

[crankin]

Nope, just disconnected at front and center.
I think I isolated the problem to the front suspension or tires.
Thanks

[Bravo10000]

Nope, just disconnected at front and center.
I think I isolated the problem to the front suspension or tires.
Thanks

You're probably looking at a tire balance issue. I say that because if it worsens when you are coasting in gear, the weight of the car is shifted forward a bit...onto the front tires.

Is this vibration primarily felt in the steering wheel?

[Bimmer93]

My 5 series is doing the same thing and I had no Trans. work done. I purchased mine about 2 weeks ago and it been doing this since plus it has new tires. I figured something out take it out for a long drive and pay close attention to the speeds below and above that speed, does it run smooth then drive it at those suspious speeds and keep it there and see does it shutter nonstop. Mine does it at 60-65 but runs smooth below and above that speed. So I called my Stepson who works at Discount tire and he said right away BAD BALANCE, I figured this out yesterday and havent had a chance to have them rebalanced but I'll let you know. KEEP THIS IN MIND IF IT WAS A DRIVE SHAFT I THINK IT WOULD DUPLICATE THIS AT ALL SPEEDS. Next if it shutters when you brake that could also cause a problem (bad rotors)

[crankin]

yes, I found that both new front tires are out of round. They sent replacements, which arrived today. Hopefully, that will be it.

You're probably looking at a tire balance issue. I say that because if it worsens when you are coasting in gear, the weight of the car is shifted forward a bit...onto the front tires.

Is this vibration primarily felt in the steering wheel?