so i need clarification, I'm going to the junkyard tomorrow to get a 83GSL rear end. I've searched and read all i can find on the matter but keep finding contradicting and conflicting answers. I have a 84GS and was wondering if the 83GSL will work with my driveshaft? Some of the threads I have found say:

81-82 have smaller flanges while 84-85 have bigger (skipping 83 entirely)

or

81-83 are smaller 84-85 are bigger

or

81-82 are the smaller flanges 83-85 are the bigger flanges

which is the CORRECT answer? Also I found that the smaller flanges have 4 threaded holes and the bigger one that would fit my 84GS has 4 NON-threaded holes. Is this a way of telling the difference?

thanks for the help -noel

 

Best bet is to just grab the shaft. Midway through 83 they changed.

EDIT: Or if you go, take a measurement of the bolt spacing on your driveshaft and see if the doner car is the same. When in doubt, pull it out.

 

All the 83's I've ever worked on which range from a 9/82 to a 4/83 production date have the large drive shaft like the 84/85's and the small axles like the 81/82's.
You are correct the smaller flange has threaded holes on the pinion flange where the large ones use bolts and nuts. The small flange'd driveshaft is notably smaller you should be able to spot it pretty easily.
However since these cars are over 25 years old a lot could have been swapped etc, so you might want to double/triple check what you are buying first to make sure.
Hope that helps.

 

The mid-year change in '83 is a myth. The fact is that ALL '83 cars use the same driveshaft as the 84-85 cars and ALL '83 cars have the small axle rear. If you look in the parts fiche, you can see this.

Of course, things may have been swapped over the years. Also, there have been cases where the car was maybe built late '82, so people thought that the car was an '82 model, but was really an '83 model (for example).

 

My car was built in 10/83, yet it took the '82 smaller drive shaft flange. It was in a wreck before I bought it.

Best bet is to match them up.

Also you could ask Mazdatrix, they are super knowledgeable.

Also if you get a junk yard drive shaft, the needle bearing probably will be worn and/or rusted and in need of replacement. Some driveshafts require that the needle bearing races be pressed out by a machine shop. It is an additional $100

 

Thank you for backing me up on this, I believe any 83 that does not have the big driveshaft and small axles has had something swapped previously.

 

so i can just use the drive sharft outta my 84GS then, thanks guys. The driveshaft at the junkyard had four non-threaded holes so i should be good to go. appricate the help. Heading back to the junkyard today to finish the job and score a few other goodies.

 

Glad it worked out, and yes the 84 driveshaft you have will work just fine.