1999 3.4 Auto 4Runner. 50k on Engine, 200k on everything else.

I am getting nasty RPM based front end vibration that starts at 3.5k and gets progressively worse until it peaks at 4.5-4.7K then it usually shifts. I just swapped a new motor in and everything seems to be secure. Motor mounts and exhaust are all tight, and i marked every bolt on the flexplate/spacers so the weight should be dead on.

I just took it out and the vibration was so bad that it started to rattle the dash before it downshifted. Its pretty much narrowed down to flexplate for me, but i pulled the cover and everything looks fine... help!

 

did you pull the drive shaft? have you checked the u joints? put it up on jack stands and i'll come over and watch the driveline spin.

 

Turns out it was an out of balance fan??

It blew up today, atleast i know what the problem was!