Hi all,
Read that 3:73 should be the max with an A4. Why is that? Also what's the difference between a series 2 carrier and a series 3. Can you replace a series 2 with a 3? How can you tell the difference? 1 more question. How will gas mileage be effected going from a 2:73 to a 3:73 (not that it really matters but don't want to be shocked or anything)Getting mid 20's with the 2:73 now.

Thanks,
Doug

<small>[ August 05, 2002, 06:56 PM: Message edited by: Jocko1960 ]</small>

 

The reason 4.10s are bad is they will need a shift to 4th before the traps. I think you can still use the 2 series carrier for 3.73s if you order them for that carrier (ring gear will be thicker).

 

Thanks.
Anyone know if there is an easy way to tell which carrier you have? For instance my car is a 99 Z28 with an A4 and 2:73 gear does that make it a certain carrier type or is it based on year model or something else? Reason I'm asking is I have access to a series 3 carrier, 3:73 gears and the ABS exciter ring and wondering if that will be a problem with what I have presently.
Any input would be great.
Thanks,
Doug

 

I'm 98% sure it's 2 series. Check your door sticker. If it says GU2 and you are sure the rear is stock then it's 100%. Usually it's 2 series for 3.08 and lower and 3 series for higher ratios.

I haven't seen 2 and 3 series side by side but I would assume 2 series is shorter or at least ring is attached more to the left for compensating the beefier pinion. That's why you need 'thick gears' if you want to use 2 series carrier for 3.23 and up.

2.73 -> 3.73 MPG losses vary, but I lost 0-1 in the city and 3-5 on the highway. The loss is less if you manage keep RPM around 2000.

 

Oh, and you can throw in 3 series carrier. But if you have ABS/TCS you don't have to worry about any ABS ring stuff as that's only needed if you don't have TCS. If you have TCS then just ingore the ring.

 

Jocko just put a converter in your car youll be happy with that i think.

 

Ok. Thanks everyone. As far as a stall converter, since I don't go to the track or anything like that I thought I would just go with the gear change. I like the bottom end torque and chirping the tires a bit when fooling around on the road.

Doug