Subject: 1998 Eclipse
Question: 1998/Mitsubishi Eclipse RS/Automatic/54,000 m.
After reaching 50,000 miles on my vehicle, I had a tune up by the dealer and everything was working fine and the car was purring.
Over the summer, a nail punctured my back left tire in which the tire was patched. The tires always felt as if they were going to fall off, so I took it in to be looked at and the tire was damaged so I needed a new tire. Instead of buying 2 tires for the rear, I bought 1 since the other tires were fairly new (had less than 10,000) on them and mechanic said that it was not necessary to buy a new pair.
Well since then, the car shakes when I exceed the speed of 60-65 mph and feels as if the car is going to fall apart. I am taking my car in to be serviced next week since the dealer warned me that I needed a new timing belt at 60,000. I would like my car to return to the same smooth ride that I have experienced over the past 4 years. Do you have any guidance/ suggestions about the shaking of the car? Any assistance would be greatly appreciated.
Answer: Gigi,
Having your timing belt replaced at 60k miles is definately a good thing to do. It has nothing to do with your tire problem, but that belt is cruicle to the life of your engine. I would guess that when they change your timimg belt, they may also recommend changing your water pump belt and alternator belt; and your power steering belt and A/C belt if so equipped. It's probably a good idea to do all your belts at once. Especially if none of them have ever been changed.

When you say your car feels like it's "going to fall apart", I'm assuming that means you are feeling lots of vibration in the steering wheel and in your seat. Typically, that means your wheels are out of balance. If your steering wheel vibrates a lot, that indicates your front wheels are not balanced properly. If you feel more of the vibrations in your seat, then your rear wheels are improperly balanced. Have your wheels checked and balanced. You may also be due for an alignment.

A very common cause of wheel vibration is not having the tires properly inflated with air. Improperly inflated tires will also cost you traction and tread life. An even more scary scenerio is that your wheels may not be tightened down properly. This is something you can check yourself if wish. Take out the lug nut wrench from your trunk (your owners manual will show you where it is) and go around to each lug nut and try to tighten it. If you find that you have loose lug nuts, that will defiantely cause violent vibrations. This will be checked if you bring your car in to have the wheels balanced.

Unbalacend wheels are not uncommon, and can become unbalanced for many reasons. Have them checked out and rebalanced and that should remedy that problem.
Good luck!