I searched, but didn't actually find an answer for this question:
Can I simply purchase new GSL-style rear rotors and disc calipers to bolt up on my GS-style rear-end? (Obviously, I'd have to get new brake lines and proportional valve, too, I assume...if this would work.)
It's time for a rebuild on my rear-end bearings, seals, etc. and I was thinking that while I was at it, I'd mount NEW disc brakes, rather than the current rear drum brakes.
On the other hand, I have found a GSL rear end that I could purchase, locally, but not sure of the condition of it and they'd want to trade for my GS rear-end, plus cash; so, I was wondering if purchasing GSL disc brake components would be a feasible option.
Thanks.

 

you also need the backing plate from a disc rear.

 

I guess I need to check out an assembly drawing and take an inventory of the components. I was hoping it would be simple to just replace my current drum brake hardware with GSL disc brake hardware, without doing a complete rear end swap (Not GSL-LE as I'd want to keep the same wheel bolt pattern as stock).

 

nope not possible... the drum rear end has a 4 bolt flange on the rear end hoising, the disk rear end hat a 3 bolt flange, sorry

 

Ok thanks.

 

My Haynes Manual and Work shop manual doesn't actually have a walk-thru for removal of the entire rear end. Does anyone know if a walk-thru exists for this on the internet? A walk-thru guide for the entire swap of a GSL / GSL-SE rear-end conversion from drum brakes would be awesome to review.

 

Check out the facts section of www.mazspeed.com, but it's really not necessary.

To get the axle out, you need to unbolt the driveshaft, disconnect the flexible brake line, the parking brake cables, the Watts link and the four trailing arms. Then unbolt the shocks from the lower mounts and the whole lot is free and clear.

 

Thanks for the link. I see that the author states, "...Use the pinion flange that matches your driveshaft (small flange 81-82, large flange 83)."
"...All 84-85 models use the larger pinion flange introduced in 83."


I assume that the pinion flange is the point at which the driveshaft is mated, perpendicular to the rear axle? Can I simply use my current 1981 model pinion flange (and drive shaft) if I were to find an '83 - 85 GSL rear end? Would the pinion flange fasten correctly to the '83 -'85 rear end to be a direct swap?

 

No, the flange is bigger on the '83 to '85 model year cars, so you'd need to match the driveshaft to the rear axle housing. That or swap a flange from an '83-'85 driveshaft onto an earlier one. (I think this can be done, anyhow.)