LargeOrangeFont

iTrader: (7)

Did all GTUs come with the 4.33 rear gear?

I just found out my car has the rear end out of a GTU. Wondering if I might have the 4.10 rear or the 4.33 rear gear?

Easy way to tell? RPM at 80 MPH?

Thanks!

Icemark

yes all GTUs models had the 4.3 rear end, however the 89-90 GTU had either a 3.9 or 4.1 rear end (depending on if it had an auto tranny).

LargeOrangeFont

iTrader: (7)

Is GTUs a seperate model? or is that refering to the early sport/GTU model?

Any way to identify which gear I have without counting teeth? I guess I could jack up the rear end and count the turns of the driveshaft...

wrankin

FAQ.

The GTUs is a separate model from the GTU. Only came out in 89&90 IIRC.

It gets confusing because people often type "GTUs" as the plural or possessive form of "GTU".

LargeOrangeFont

iTrader: (7)

I read the FAQ and it was just as confusing as that statment above. Thanks for the clarification.
Based on the FAQ the 89-90 GTU did not even have a limited slip diff. The car definately has a limited slip, so I would assume that the diff came out of a GTUs, which does in fact have the 4.33 rear end? But it says nothing about a 4.33 anywhere in any of the specifications.

Were ALL the GTU manual?

CLH

How do you know it has an LSD, and why would you assume that it's from a GTUs? With the low production numbers of the GTUs the odds that your car has a transplanted GTUs diff are pretty low. I would consider it more likely that you have a diff from an S4 GTU, which is a better LSD than the GTUs had anyway (clutch-type vs. viscous).

If you believe that your car has an LSD because there is a 'Limited Slip' gear oil tag on the drain plug, then what you have is a clutch-type diff - which is definitely *not* from a GTUs. Give us some additional info to work with and we can be of better help...

LargeOrangeFont

iTrader: (7)

The guy I bought the car from owned the car for 18 years. He said he bought the hubs, brakes and diff from a GTU. I dont know if he meant GTU or GTUs. I've been driving the car on the street and the track and it definately does not have an open diff.

I am leaning towards the possibility of the diff being out of a S4 GTU as well. There is not a tag on the drain plug that I remember (it has been a month since I had the car on a lift) but I will check specifically for that in the next couple days.

If it indeed has the S4 clutch type LSD out of a GTU is it safe to assume that it has the 4.10 rear end? Or did the S4 GTU come with the 4.33? I don't have any other RX-7 to reference, but based on how the car runs and pulls through the gears, I don't think it has a 4.33.