hey,
On the weekend i put a irs from a bf with a 3.45 diff into my falcon ba xt, everthing lined up perfectly and bolted in fine, put the tailshaft weights back in the right place, took her for a spin and there was a terrible vibration from roughly 60kms onward.. is there anyway the xr6s take a different tailshaft to the standard xt models, a seen a line on the diff there was one on my old one too, i was thinking that is the diff lined up to the tailshaft in a specific way?

im outta ideas.. if anyone could help would be appreciated...

Thanks

did you align the subframe using aligning pins? if the subframe is out of alignment it will cause vibrations as well

i would say so.


maybe try undoing the tailshaft and spinning it a bit and line up a different set of bolt to see if that makes it better / worse?.. then it will just be a case of elimination till you get to the right spot.