So i have a 83 gsl rear i want to p[ut into a 84 gsl (the 84's rear is drivable but is bad..) is it possible to switch it?? i just read that the 84 gsl's rear is bigger... sooo will that be a major loss?? is it worth it? or should i look for an 84-85 year rear?

thanks guys

 

You can swap the entire unit. There are internal differences between 83 and 84. They look identical, until you pull out the axleshafts. 84/85 Axles are larger diameter on both ends, as are the axle bearings and spider gears.

 

but is it gonan be a power loss or anything??? or will i not notice any difference?

 

The rearend doesn't make any power at all.
Unless you are pushing ~300+ HP, the 83 rearend will work fine.

 

When you say its bad, do you mean the differential (3rd member), the halfshafts, or the housing is bad?

You can replace the wheel bearings on each halfshaft, and have the differentials main and pinion bearing setups re-done. Replacing the differential with a low wear good unit is cheaper than rebuilding. If the housing is bent then replacing the entire rear assembly is a chore.

Either way, here is more info in the form of a reference: http://www.mazdatrix.com/g5.htm

gl2ya