scremn8

i don't think it's the road pretty sure it's not. the roads are kept up. but then it might be so cause i was in the truck. but still confused at why i did not fill anything at 95 or even 96. but at 100 it was really noticeable..i thinking it might be the tires also. some tires have diff. speed rating....

AF-RX8

It might be the tire balancing is very slightly off or a wheel is slightly bent but it is sooooo slight that you only feel it at very high speeds.

Check out this link http://128.242.141.111/

It is for the Hunter 9700 wheel balancer and it has a locater so you could enter your zip code and find a shop near you that has one.

This machine is amazing and will tell you if it is the tire or the wheel that might be causing it. It could be a slightly out of round tire that 99% of the balancers would never detect.

I would go on a day when there is no rain or snow on the ground because beleive it or not this machine is so sensitive that a wet tire would actually balance slightly different due to the weight of the water. I know it sounds crazy but the machine is that good.

Hopefully this solves your problem though to be honest I wouldn't really be too concerned of a vibration at 100 mph ...

Shamblerock

AF, I am not a mechanic. When I here people talking about vibration I am not sure is they feel the steering wheel physically moving/shaking in their hands. I have a slight high frequency "buzzing" type of feeling or sorts and I'm not sure if this is what you guys are refering to. Its kind of like touchining an electirc motor vs a gas power motor. So thats why I thought that maybe its because it is one of the rare cars that have electric powered steering.

AF-RX8

Your describing it pretty good ... from your description I would say its a buzzing type opposed to the vibration type. The wheel does not physically shake or move ...

When you feel this 'buzzing', is it when your driving or when you are actually turning the wheel. I would think if it happened when turning it would be the power steering motor.

Mine has this buzzing feeling when driving sometimes depending on the road surface when when racing up the rpm's so I think it is not related to the power steering motor but more of a normal type of roadfeel our cars have.

To explain it even more, there are plenty of times when normal driving on smooth surfaces I feel nothing but then others when accelerating to the high rpm's or riding on a unsmooth road that I would feel it.

Shamblerock

I feel it a various different times but it is so minor and such a fine buzzing, I don't notice it anymore and it doesn't concern me. Actually I would bet money it is probably the electric power steering motor that drives it. There are absolutely no ill effects whatsoever with the steering of the car and in fact ift feels so well weighted and balanced. So, until you start hearing funny noise or deficiencies in the steering, don't go chasing the "problem" because I think its just the way the car is.

scremn8

i could more likely go with the wheel balancing. it was a vibration this i'm sure of. why it happened well thats a diff. story. and i've never noticed a buzz feeling before, but then i did not know about the electronic steering either. but yep vibration, i guess my car is telling me to keep my speed low.. but i was told if i did that i'd be a wimp...

AF-RX8

Shamblerock .. I always chauked it up to good roadfeel translated through the steering wheel until some here say there 8's steering wheel is smooth as silk ...

I can't imagine how the steering wheel would feel 'dead' when it tranmits road feedback so clearly ... the problem is not many people are actually posting on this so it can be some people don't understand what I am talking about and they don't know what to look for.

AF-RX8

Quick update on this thread, I drove my stepfathers RX8 and his had slight less vibration then mine at 40mph and over.

I decided to rotate my tires since I had a feeling it was an unbalanced tire causing it being that the vibration was felt at 40+ mph ...

I swapped front to back and back to front ...

Car is much smoother now ... I can't beleive the difference ... I never thought to have my tires balanced eventhough when my rx8 was brand new there was a vibration through the steering wheel where the wheel actually shook side to side (classic balancing or tire out of round problem) but after 700 miles it mostly went away ... I kept thinking I should have the front tires balanced but never did it.

Anyway ... I hope this thread helps someone in the future is they need a reference to it.

Shamblerock

Glad to see that you got rid of some of that vibration.

Zaman Abbas

I have the steering vibrating issue during speed above 100 KH, since I purchased new 4 month back, I complain to company they said this manufacturing fault they cant do anything.
I strongly recommend not purchased MG Cars