whole car vibrates where speed is from 30-40 mph
?

 

Have you switched rims or tires lately?
hit a big pothole?

 

Sounds like it could be a balancing issue. Usually if the vibration doesn't improve as you speed up it's alignment (or loose lugs).

a 10 -15 mph window of vibration points to a balance issue. Bang a pot hole or curb hard enough and toss a wheel weight and there you have it!

 

the only difference is that tires were emptied and re-filled with nitrogen-air mix. They had the same mix before.

i'll check the tires and rims anyway

thanks!

 

...So the old air got stale, and you got new air? Just don't forget to fill your blinker-fluid tank!! JK on the last part, but could not resist!!

OK...OK...I'll give you the fact n2 filled tires hold PSI better and require less care to maintain PSI to get slightly better mpg (now with built in tire PSI monitoring this is negated),........but mostly a up-charge at tire places to increase the average bill...a few folks who race MIGHT see a benefit.

But to get serious, if the tires were removed from the car to be filled, and the mounting surfaces not cleaned, that could be an issue, just like if the rims are aftermarket, and use hubcentric rings, one might have fallen off...
Safe to say the tires were rotated? if this was done without balancing...from rear to front, now you can feel it...before you did not...you MIGHT have a bent rim, or a wheel weight missing....
Good Luck! when this crap happens it is a pain, but remember, smile, and you can never be mad driving a MINI!! It is simply not allowed!!

 

I also get a vibration around those speeds. I have changed both my wheels and tires recently. Not sure what's causing it since I have exactly the same wheel and tire setup as the Stock cooper S 17" wheels and 205/45 tires :( I've had it balanced and aligned and still the vibration persists :( it goes smoothly at lower speeds tho :(

 

However I do have hubcentric rings. Could a crack in one of them cause vibration too ?

 

Sounds more like a power steering issue. You should check the fluid level.



Or...you could go to a good alignment shop and have them check it out.

 

Sounds like a missing wheel weight.

And I'd suggest ditching the whole nitrogen-air mix thing. Has no benefits, except to the person you're paying to do it.

 

Hello All

Problem Solved!

1. Wheels were disbalanced. Wheels balancec!
2. One rim was bent due to pothole. Wheel replaced!

Now runs better than before.

Thanks to everyone who contributed.