I bought a 1998 Oldsmobile Bravada about 4 months ago. It has about 114k miles, most of which were put on it by the original owners who were an older couple, so it was babied. The whole time I have had it it has had some sort of intermittent deceleration issues, meaning when I decelerate or shift down hard at a fast pace from different speeds under different circumstances it will "shutter" in the front on what feels like the passenger side. I can accelerate out of it each time. It also doesn't seem to have an effect on steering. It happens far more often when I drive over 60mph and then decelerate. At the higher speeds I also notice that same side feels like the wheel bearing is going out as it shakes noticeably but I've had those checked and they are fine. The following are repairs I've had done to the vehicle to attempt to solve problem:

Transfer Case fluid change (had wrong fluid in it when I got it)
Lower ball joints on both sides replaced
Idler Arm replaced
Alignment

The above repairs needed attending regardless of whether they were going to fix the problems or not so I figured it couldn't hurt. I would really appreciate some input on this as I don't have too many options on this one right now.

 

Check your upper ball joints for movement and recheck that wheel bearing. Shake the tires side to side and up and down(im sure youve already done that). Also if its 4wd check the front drive shafts! If youre feeling vibration at high speed have the tires balanced. Just trying to help brainstorm and come up with possible issues! Unfortunately the blazers arent exactly geared for racing so quick deceleration can be common.