Toyota Repair: 1993 Tercel Front end Shaking, steel fibers, manual car

Question
I have a 1993 Tercel 5 Speed Manual car. When Im in 4th gear doing 50 mph the front end starts to shake, BUT if I shift to 5th gear it stops. Than if Im in 5th gear doing 60 mph it shakes also. Again I can downshift to 4th gear and it stops!! Do you have any idea why it is doing this??? When we first got the car the driver side brake was locking up ALL the time so we replaced all the different componets of the brake and that helped with the shaking. We also rotated the tires witch helped. But now it has started again.... Please help!! Thank You.

Answer
There are many reasons why a car will shake at certain speeds. First, it could be the steel fibers in the tires are offset. Second, it could be that the tires are bad or need to be computer balanced at a tire shop. You might want to consider at least getting your front end aligned; however, I would recommend compensating all 4 wheels. When they do this, they will hopefully inspect the steering system which could be another issue. Is it doing this when you brake or just when you're accelerating?