Re: Gearbox or something ele?!
Hi Joey, wheel balancing and tracking problems will be related to the speed you're doing rather than the engine revs, although the less vibration you have (through using a higher gear) the more noticable they'll be.
I think an unbalanced wheel may show particularly badly around 70mph and maybe 90mph if I remember right but be less bad at other speeds.
If the steering wheel vibrates then a front wheel is unbalanced, if it doesn't it might be a back wheel.
Does that sound like it might be the problem?