A/G-series diff compatibilty

[JustCallMeOrlando]

Hey all,

A-series diffs aren't exactly thick on the ground, and when my car gets a V8, it's going to need an LSD.

Someone has drawn my attention to the fact the G-series diffs in numerous other cars may be able to be jammed into an A-series housing. If anyone has any first hand experience, this means you John, can you please divulge as much as you can? I'd like to dispel all the hearsay surrounding it?

Cheers,
Nathan

[whatthe?]

I'd also be interested, but only in someone who has actually put a G series centre in the JZA80 housing, as it seems a large % of newer toyota/lexus RWD vehicles have diffs of different sizes that have an A series classification (according to the build plates anyway)

[whatthe?]

Case in point, GXE10 IS200. I know for a fact that the internals of this diff are identical to F series (put a TRD LSD in a couple of weeks ago, 7.5" F series centre, same TRD part no. as the item for an MA61)

Yet here it is on the build plate, axle code A01A

All is not as it seems....

[JustCallMeOrlando]

Which is exactly the same as what my ID plate says

[Soarer21]

Funky code challenge there whatthe.
I cant answer it, cause Ive only done the switcheroo on the JZX90/100 diffs for my JZX90 race car. Its diff code is A01C which clearly differs from the 7.5in unit in your GXE10. Perhaps we should be quoting last digits as well? Im now interested to know the full code on the JZA80. Maybe its A01x? With a different digit thereby denoting a different specification altogether.

However, with my situation using an A01C diff housing I fitted up a TRD centre that I took from a JZX81 housing. The JZX81 most definately had a G series diff code on the build plate. The 4.3 ratio gears were provided by Duncan at TopCog in Caloundra who does all my diff and gearbox work and he stated they came from a Hilux he'd had on the shelf. Later on I bought a new 4.556 ratio crownwheel and pinion set from Toyota which was also a G spec and had this fitted to a second A01C housing with another LSD unit.

Anyway, based on the pic above showing the IS200 having an "A" spec diff, Id say the "A" is no longer a reliable means of identifying what you have/need.

We do know now however that A01A is 7.5in and A01C is 8in

[Soarer21]

Originally Posted by JustCallMeOrlando

Which is exactly the same as what my ID plate says

So you have a JZA80 SZ with an A01A diff code?

[Draven]

my puppy (2000 6-speed TT) has an A03B

and it looks phyiscally bigger than any 7.5 diff

[whatthe?]

Originally Posted by Soarer21

Funky code challenge there whatthe.
I cant answer it, cause Ive only done the switcheroo on the JZX90/100 diffs for my JZX90 race car. Its diff code is A01C which clearly differs from the 7.5in unit in your GXE10. Perhaps we should be quoting last digits as well? Im now interested to know the full code on the JZA80. Maybe its A01x? With a different digit thereby denoting a different specification altogether.

However, with my situation using an A01C diff housing I fitted up a TRD centre that I took from a JZX81 housing. The JZX81 most definately had a G series diff code on the build plate. The 4.3 ratio gears were provided by Duncan at TopCog in Caloundra who does all my diff and gearbox work and he stated they came from a Hilux he'd had on the shelf. Later on I bought a new 4.556 ratio crownwheel and pinion set from Toyota which was also a G spec and had this fitted to a second A01C housing with another LSD unit.

Anyway, based on the pic above showing the IS200 having an "A" spec diff, Id say the "A" is no longer a reliable means of identifying what you have/need.

We do know now however that A01A is 7.5in and A01C is 8in

So what we need is someone with a IS300 to confirm that A01C is the code on that car (which would substantiate what Ive heard about G internals fitting) and someone with an N/A JZA80 who isnt blind (I'm looking at you Nathan ) to let us know the code on the build plate there.

All very interesting...

[whatthe?]

Originally Posted by Draven

my puppy (2000 6-speed TT) has an A03B

and it looks phyiscally bigger than any 7.5 diff

But still an A series

[Draven]

*runs off to check the IS300*

edit: IS300 has a B04B

[whatthe?]

Yep, I dont get it

[Soarer21]

Originally Posted by whatthe?

But still an A series

It has an A prefix but the suffix is B so I wonder how that alters things.

A01A must be 7.5
A01C is definately the 8in

This recent code for Toyota is annoying. Wonder how you tell if its LSD or open?

And now to throw another spanner in the works...

Just checked another JZX90 build plate which showed another A01C but then looked at another which supplied the diff housing and torsen centre for my 4.556 setup and wouldn;t you know it, the plate says it has an A02D!!!

Also checked a UZZ31 V8 Soarer and it reads as having an A01A in it. I wouldn't have expected that behind a V8 if it truly is a 7.5in diff.


So anyway, I can confirm that A01C and A02D can both utilise G series components having done so myself.

[whatthe?]

Yes, but I'm pretty sure the IS300 wouldnt have the 8.7" JZA80 B series, yet the code is B04B apparently

And the UZZ31 is on the TRD parts list sharing the same part number as JZZ30, JZA80 N/A and JZS14x. I'd bet none of these are 7.5" centres, no matter what the build plate says

It dont make sense I tells ya!

[Draven]

none of this apparently shit

[Draven]

apparently (according to the NZ MKIV site)...

JZA80s with an a-series are an 8" diff. The number is the ratio code. the last letter is the type of diff (a=open, b=torsen)

As matt sai9d, I seriously doubt toyota stuck an 8.7" monster of a diff behind the little 2jz-ge in the IS300.

[whatthe?]

But JZA80 "A" the same as G? That's the million dollar question....

[whatthe?]

On a side note, your IS300 has a torsen? What's your address and when will everyone be out next?

[Draven]

dunno... because I'd love to know what the "c" and "d" codes mean with toyota's weird new diff codes.

The IS is not for parting out. if it gets crashed, the diff becomes a spare for my JZA80

[Soarer21]

Originally Posted by Draven

apparently (according to the NZ MKIV site)...

JZA80s with an a-series are an 8" diff. The number is the ratio code. the last letter is the type of diff (a=open, b=torsen)

As matt sai9d, I seriously doubt toyota stuck an 8.7" monster of a diff behind the little 2jz-ge in the IS300.

OK, well the A01C was a JZX90 Tourer V Mark2 with an automatic transmission
The A02D was a JZX90 Mark2 Tourer V with a manual transmission

If the Supra site is right, then an A spec diff is an 8in same as the JZX90 diffs Ive played with and therefore the G series parts should fit.
As with a lot of things though, the proof of the pudding is in the tasting... So go taste your diff

[Draven]

how about no?