Has anybody ever installed gslse axle shafts into a non se rear end?

Have not been able to find any info on this, I know it is possible to swap the whole axle assembly but I can not find information on dimensions of gslse axle shafts vs non se axle shafts or if there are any differences besides the hub bolt pattern.

 

The issue with this is that the early axle housings (pre 1984) are all small bearing axle housings. 84-85, maybe even late late 83, used a larger diameter housing and Mazda increased the axle bearing size with it. So, if you have a later housing, you could swap in the SE axle shafts and differential. If you have an early car with early small axle bearings, this will not be possible. The reason you don't hear about people swapping in the axle shafts and differential is because you would be hard pressed to find someone to sell those three parts without the rear axle housing itself. It's actually easier ro swap in the entire rear end as an assembly. All of the parking brake and disc brake provisions will be there if you go that route. You will still need the SE parking brake cables and SE brakes. You will also want to replace the front spindles and brakes with SE brakes as well. This way your brakes will match and so will your wheels. The SE has a different bolt pattern for the wheels vs a non GSL-SE. And for the brakes, lets not forget the booster, master cylinder, and proportioning valve from the SE as well. Its not just a simple rear end swap unfortunately.

 

All '84-85 disk brake rearend housings are the same part number. (Drum are different flange pattern at the bearing end but otherwise identical dimensionally) The GSL-SE and 12A axles are the same from the bearings in. The GSL-SE axles are 15mm longer between the bearing and the hub.

'83 and earlier have a smaller axle bearing so those housings won't work.

I used to swap parts between big bearing 12A and GSL-SE all the time, first putting 12A axles and brakes on GSL-SE housings, then putting GSL-SE axles and brakes in big bearing 12A housings, depending on what I was running at the time and what replacement housings were available.

All this information is/was available online, but because the web pages are like 30 years old, the search engines won't give you a hit.

 

Ah so it is 15mm!

For the OP, I can provide you my builds example.

My car is an original 1982 GS 12A. I sourced:
-Large bearing rear axle (84/85 GSL or -SE as Peejay mentions)
- LSD diff unit from a GSL-SE
-84/85 GSL rear axles, calipers, and discs (4x110)
-GSL or -SE parking brake cables

I also have a set of -SE axles, calipers, and discs ready to go. In this case, I could simply swap those in and have a -SE rear end with 4x114.3 hubs.

 

Main reason why the GSL-SE axles are longer is because it has vented rear disks and therefore its calipers are also specific to them.

So weird Mazda made this brake setup for this one trim level and only on the RX-7. Searching the part number for the brake disk only shows them in this application.

 

The GSL-SE has 40mm offset wheels vs. the 12A cars' 25mm offset. The longer axle is to keep the track width the same. Or the higher offset is.

The 4x110 cars used wheel bolts because the wheel hub face was smaller in diameter than the front brake rotor inner diameter, and they couldn't use a press in stud without making a heavier/more expensive 2 piece hub/rotor where the rotor bolts to the inside of the hub. I wonder if the whole reason for the hubs getting pushed out was so the rear studs could be replaced without having to remove the axles for clearance. Probably not.

Vented rotors *should* not matter for rotor hat height. I have a car with 330mmx32mm vented rotors and there is almost no hat height.

 

also 12A Turbo in Japan

 

The GSL-SE seems to be the 12A Turbo car with the Cosmo/Luce 13B Super Injection engine.

And the 13B Super Injection engine seems to be a mix of 12A Turbo fuel injection and intermediate housing, 12A 6 Port end housings, and 13B rotor housings...

In many markets, ALL Series 3 got the larger bolt pattern. I assume that they also got the bigger brakes and 14" wheels.