Regarding the "A03A"...that is where the confusion begins. It is entirely possible that the current codes do NOT mean the same today as they used to in years past. I personally think that the odds are that it is more likely that we (3rd gens with 2wd) actually have 8" diffs. Especially with the comments from Gadget, Flygenstein, and others. Gadget is the only one here who has installed a 913A321 in his rig. Only problem is that his is a 4X4. Still waiting for someone that has actually had experience installing the LSD in a 2wd rig.

 

Gadget has ARB's in his 4X4 4Runner. My guess is that he put the Tru-Trac in the 2WD Red One. Not the 4X4 Silver One.

 

I also have a rear locker in mine however its not a selectable so it could be considered an LSD, lockrite 1610 or whatever the number was for it
and yes im a 2WD!!! WE HAVE 8 INCH REAR DIFFS!!!!

 

Ok. I called Toyota customer service at 1-800-331-4331. The first rep found most of the info on my truck based on the VIN and my 2002 SR5 4x4 has 4.10 gears.

She had to transfer me to another department that had access to more research materials to find out what size the diffs were. The girl put me on hold for about 5 minutes and came back to say I have a 8 INCH REAR DIFF based on my vin number and model year. This information is located in a book they have called "New Vehicle Features" If you want to find out what you have call in and ask them to check this resource.

Again, on my 2002 SR5 4x4

Front diff = 7.5"
Rear diff = 8.0"

 

Hope the orginal poster got this figured out.

A question and some advice for he or she who posted first. If you've already made up your mind about what you have, why ask? It is perhaps a waste of your time to argue with the experts since you certainly won't change their minds.

Just some food for thought.

 

Ok one more update and I think this should cover it.

For the 8" Toyota diff the TrueTrac part number is 913A610. This is UPDATED from the 913A321 as the part was re-designed to be stronger and given a new part number.

Hope this helps someone out. I'll be getting one in the next couple months to wrap up project SportRunner.

 

I just got a quote to get a Truetrac installed at a local performance shop. The guy quoted me $655 + fluids. That seems AWFULLY high to me. Am I just a cheap skate?

 

I got the same thing quoted for me @ Sams offroad here where I live (respectible offroad place): TrueTrac + install + tax for $850 something. The install is expensive! (I think i was quoted 320 or so for the truetrac)

 

OK, maybe I'm just a cheap skate. They told me to bring the TrueTrac in with me, so I have to buy it online. Labor only was $655, just seemed high to me. Things have changed since I had the gears swapped in my 91 4x4 for $200 per axle

 

So who is still convinced they have a late model, 2wd, 7.5" rear diff?

The question has been answered, I am waiting for the crow.