[HWYSTR455]

Originally Posted by zippy

You meaning Hub flange to wheel opening lip? My TA, the drivers side sticks out further from the wheel lip than the pass. 275/4518. But have had to roll the DS rear inner fender to minimze tire rubing Pass side fine. Is that common for them (axles) to not be centered in firebirds?

My understanding is in order to maintain the same axle length on both sides the housing was offset to the passenger side, but maybe I have the side mixed up?

The reason it needs to be offset is due to the pinion to ring gear relationship. The offset allows the centerline of the pinion to be on the same plane/centerline as the rest of the driveline.

So the side the ring gear is on the housing is further to the outside the body.

The choice GM had to make was, make 2 diff length axles ($$$) or offset the housing.

Others may have more detailed info on this than I do, but i came across this at one point trying to fit the largest wheel/tire combo as possible (in the early 80s).


.