Oscillating Light Rumble when driving at 70mph

[Vx-Mad-G]

Hi,

I went to test drive an Astra-J 2.0 CDTI 2011 last week and when I drove it, it was splendid, however when I got to 70mph under my seat I could feel what can only be described as an oscillating rumble, not loads, but like something was grinding. Only happened and 70mph, when I slowed down, it went away, and when I went over 70mph it went away, literally between 68-72mph.

Any ideas what that could have been?

Car is still available, if its something minor, I could go back to it.

My thoughts were tyres, discs or brakes, but all of these were brand new about 3 months ago and premium brands, my other thought was a bearing??

Whats your thoughts.

Regards,
G.

[andy2174]

Could be a wheel bearing, damaged wheel or wheels out of balance ?

My Sri, which runs on 18"'s is as noisy as hell on some road surfaces, not sure what tyres were on the Astra you drove, but mine has RE050A's and apparently they have pretty stiff sidewalls

[Vx-Mad-G]

The Astra I drove was on Continentals, which were 3 months old. No wheel wobble at all, which made me think it werent balancing. Only thing I thought was drive shaft or bearing.

[tucpal]

best to check the wheel weights are on the alloys
jack car up and check for any play etc it may be best to get your local garage just to check it out just to be sure everything is ok