I love my MCS and maybe I'm starting to get really picky but
Around 60-61 MPH I'm noticing a very slight vibration, just in that speed range and does not always do it. And its not constant, its almost like a resonance, like a turboprop when the props are not quite synched. Anyone notice this with theirCooper ?

 

Thats a tough one. Often vibration at a specific speed can be because a wheel is not balanced correctly or alignment is slightly off. But usually that would be consistent.

But with your scenario, I guess I would just drive 59 or 62

 

How many miles do you have? Has it been there since you picked up the car? I had the same issue in my first MCS from day one and had the dealer balance the wheels several times. Finally had them replace the wheels and it was gone.

 

And where do you live? this could be part of the problem.

If you live in a snowy part of the country and your problem is intermittent then you could be having some snow pack in one or more rims that throws the balance off. I have this once in a while after being at work during a snow storm. The sind blows and packs snow in the openings of the rim and until I take it out the wheel will be out of balance because of it that I get some wierd vibrations.

 

It's a wheel weight issue.

Like schatzy62 said it could be ice/snow. Take it to car wash. If that doesn't work, head to your local tire shop and have them balance the wheels.

If it's not either of those then it might be a tire issue.

 

I've had the same issue on my 2010 that I picked up in August. It's been going on randomly ever since. The wheel weights have been checked, and re-torqued.
I'm going to have the wheels checked to see if they're out of round, but that's a last resort for me. Luckily it only happens intermittently, so I'll hope for the best.

 

Yep, thats the funny part. It only happens intermittently. Makes me think some kind of harmonic vibration thing happening ???? No biggie but I think I'll have dealer check it out when I get oil changed at 3000 miles.

 

It could also be tread separation in one of the tires, but I'm betting on tire balance.

 

Just in case rebalancing does not take care of it, it is possible that you have a "bad" tire meaning it does not roll with a uniform force against the road. I have a 2008 Hyundai Santa Fe that had a vibration such as you describe from new. I went round-and-round with the dealer through two complete tire rebalances until they put it on a road-force-variance tester (http://www.gsp9700.com/index.cfm) and found that one of the tires had twice the maximum force variance allowed for that particular type of tire. They put on a new tire and the problem was solved.

 

When I worked for a Dodge dealer a few years back the new body style Durango has this issue. Turned out to be a bad batch of Goodyear tires that were installed on around 10k vehicles. Tire/wheel would balance perfect on our balancer but when taking a shop that tested uniform force it was plain as day.

To this day I refuse to buy Goodyear tires. It created so many nightmares for dealers and customers since Chrysler refused to acknowledge the issue for weeks.