13 replies to this topic

[hellosubaru]

I'm attempting to swap in an '01 Outback rear diff into my '87 GL. They look like they are exactly the same on the outside, so I think they should bolt right in:





My question comes in with the axles. On EAs, there are stub shafts in the diff. On EJs, the axles spline right into the diff:

EA:


EJ:


What is the best option for putting rear axles in? Will EJ axles just spline right in, or should I transfer the chunk from the EA diff to the EJ housing and put the EJ ring gear on the EA chunk, that way I can reuse the stub shafts and axles from the EA?

The whole reason for the diff swap is for changing to 4.44 gearing w/LSD.

Thanks,
-Jason

Edited by hellosubaru, 03 October 2012 - 10:02 PM.
Corrected terminology

[Crazyeights]

Perhaps the inner cups for an EJ axle will fit on an EA inner joint. You can probably make this work by mixing and matching axle parts. Is this RWD only? If not do you also have the matching trans (with 4.44 front diff) installed?

[hellosubaru]

Perhaps the inner cups for an EJ axle will fit on an EA inner joint. You can probably make this work by mixing and matching axle parts. Is this RWD only? If not do you also have the matching trans (with 4.44 front diff) installed?

Yes, I have a 4.44 5spd trans.

[suberdave]

if you get the correct rear shafts from a GL. i believe they are 7/8" diameter. with 22 splines, the inner cup from a WRX axle will fit onto the GL shaft, and will fit right into your car...

-=Suberdave=-

[Gloyale]

Custom axles (mix n match cups)

Or swap the EA carrier into the 4.11.

You will also need to swap to the EA input flange. The '01 diff has a larger flange won't fit your driveshaft.

[hellosubaru]

Custom axles (mix n match cups)

Or swap the EA carrier into the 4.11.

You will also need to swap to the EA input flange. The '01 diff has a larger flange won't fit your driveshaft.

Awesome, thanks all. I think I will go with the carrier swap so I can use the stub shafts and original EA axles. I'll post up pics when I'm done.

[czny]

Don't forget to measure your bearing preloads(turning torque) of your ej r160 at the pinion fully assembled with a inch-pound torque wrench(about 27-35 in-lb). Then measure the pinion preload with the carrier out(about 12-15 in-lb). You don't need to remove the pinion from the ej case - just change the companion flange & tighten to correct preload.
You'll want to duplicate these figures for long brg life. Keep R&P backlash at .004-.008"(measured with dial indicator at outside teeth of ring gear). Measure the shim packs from both diffs to determine which way you need to shift the ring gear.
Find some Prussian Blue paste at the auto parts & run your contact patterns.
You want an elongated olive shape - most of that contact toward the toe(inner diameter) of the ring gear.

Edited by czny, 06 October 2012 - 09:19 PM.

[hellosubaru]

Don't forget to measure your bearing preloads(turning torque) of your ej r160 at the pinion fully assembled with a inch-pound torque wrench(about 27-35 in-lb). Then measure the pinion preload with the carrier out(about 12-15 in-lb). You don't need to remove the pinion from the ej case - just change the companion flange & tighten to correct preload.
You'll want to duplicate these figures for long brg life. Keep R&P backlash at .004-.008"(measured with dial indicator at outside teeth of ring gear). Measure the shim packs from both diffs to determine which way you need to shift the ring gear.
Find some Prussian Blue paste at the auto parts & run your contact patterns.
You want an elongated olive shape - most of that contact toward the toe(inner diameter) of the ring gear.

Thank you for bringing this up. I was talking to my friend about this (who does rear end and trans work all the time), and he thinks it would be a better idea to get the EJ inner cups and mate them with the EA axles, so I don't have to mess with all of the preloads.

Thanks again!

[Gloyale]

Thank you for bringing this up. I was talking to my friend about this (who does rear end and trans work all the time), and he thinks it would be a better idea to get the EJ inner cups and mate them with the EA axles, so I don't have to mess with all of the preloads.

Thanks again!

NAh.......overthinking it.

People swap carriers all the time. It's easy.

Making hybid axles is a mess, and next time you need an axle, you'll need to another hybrid axle.

either wll work.

[czny]

Tearing down the LSD carrier to remove the nut buttons from inside. Cutting grooves for the slip-in sub axles. Clean up & reassembling the LSD. Trial assembly & checking the fit.

Agreed - a lot of extra work for hybrid axles.

[hellosubaru]

Haha, right on, sounds like I'll do the carrier swap. Thanks again guys for the advice and pointers. I'll post back here when its done on how it goes.

[suberdave]

really you think its easier to swap the carrier, than it is to pull the inner joints off of a few axles...

bring me 2 EA rear axles and $25 and ill send you home with 2 bolt in axles...

i have many sets of WRX inner joints in my shop.

-=Suberdave=-

[el_freddo]

really you think its easier to swap the carrier, than it is to pull the inner joints off of a few axles...-

Personal opinion of mine: If I can put in a little more effort in an area that will allow me to buy off the shelf replacement products then I will go to that effort.

When it's drive shafts we're talking about, they come into this category for me.

Cheers

Bennie

[Gloyale]

i have many sets of WRX inner joints in my shop.

That's why it's easier for you. Break an axle, build another.

Most people would find it easier to replace with an off the shelf option. EA rear axles are cheap at junkyards and seldom break in stock rigs.

All though, the hybrid axle is arguably the stronger setup.