i'm wondering if anyone knows what color the speedometer gear is in side the tranny for a 3.73 rear-end. i have a yellowish/tan one in there now and it must be for a stock 3.23 or something cuz its off by about 20 mph at 60... anyone know what color it is for a 3.73 gear ratio?

 

Your friendly Chevy dealer parts guy. I May still have mine, I'll look tonight.

 

There are two "types" large(older cars) diameter and small(newer ones). These are small diameter. The one for the 3:73 gear is red (21 tooth).

 

http://www.tciauto.com/tech_info/speedo_gears.htm This is how I got what gears to use. Had to change both. Needed a 15 tooth (grey) and a 44 tooth (dark grey) for my 88 GTA with 3.73's and a 700R4. Speedo is certifiable it is so close!

 

A 21 tooth red is for a T5, and it sounds like he's asking about an automatic.

 

I have a T-5 and I am switching from 3.08s to 3.42s, anyone know what speedo gears I will need.

 

Yes it is. My mistake for assuming a 5 speed.

 

A 7 tooth purple drive gear (meaning you will need to pull the transmission to install it. You have a red 9 tooth now). And a 19 tooth driven gear. I dont remember its color.

 

so what gear color combination do i need with my car? with 3.73 and a 400-turbo? this **** is a bit confusing to mix and match...