hello im new to this place so forgive me if this isnt the place to post this,
i own a 89 s-10 4.3 blazer ive had it for about 3 years and its never given me a problem until i took it about 3 weeks ago to go get new brakes all around and new rotors for the front then ill say a week after that i took it and got 2 used tires one in the front and one in the rear, so now my problem is maybe a week ago it started shaking real bad when i reach 75 and now just the other day i notice its doing it when i reach 60 now and the shakes are even worse, to me it seems like its coming from there rear, but i really have no clue??? can it be the used tire was bad or is it something else

 

Since it didn't start until after the tires were put on, that would be the first thing I would look at. I understand saving money, but used tires are rarely a good idea. Are they the same size as the other two?

 

Rotate and balance might help, It has been my experience that bad tires can cause a lot of vibration.

 

cool thanx a bunch, and im pretty sure there the same size, im gonna try to rotate em tomorrow and then ill see whats up.