vibration?
 

okay people, I have onother problem. I am getting a vibration in my car in first gear around 5000k and second gear around 2000k. It only happens when I get on the accelerator hard. I am thinking maybe it is the drive shaft since that is the only two gears its happening in. When i bought the car someone had put brand new tires on it so maybe it could be the tires are out of balance. This is my first rear wheel drive car so Im not familiar with how the car reacts when the tires are out of balance. F.Y.I I have 99 mustang GT with only 45K on it and manual transmission. Was well taken care of. If it is the driveshaft how much would it be to re-balance it?

Ok, I will try my hand at this one. If the wheels are out of balance, the vibration will ocurr within a speed window like say 35 - 40 mph and won't be rpm related. From my experience, I generally see this problem at higher speeds such as over 70 mph if you have a balance problem.

I know that 5,000 rpms in 1st is not the same mph as in 2nd at 2,000 rpms. Does not sound like a wheel balance problem to me, but it's cheap to do, so I would balance them anyway.

As far as the driveshaft is concerned, the same would be true to. In other words, the driveshaft would vibrate whenever it is spinning at the same speed. This would be directly related to engine rpms right? I have no idea about $ for balancing the driveshaft, but if you did have a problem you might just be better off buying a new one... a high performance one. They are not expensive.

But hear is another thought: since you have not had a rear drive before, you might just be feeling the limited slip working. There is a lot going on with that drive train when you stomp on it. Could also be some wheel hop too if the suspension was modified and not done correctly. Is the suspension stock?

LIMITED SLIP
 

THE GUY AT THE SHOP TOLD ME IS THE REAR AXLE, THERE IS SO MUCH TORQUE THAT IT VIBRATES A BIT. I AM JUST NOT USED TO IT. IS ALL MUSTANGS LIKE THIS 5 SPEED?