What speedo gear for AOD's?

[Idwitheld-1`]

Search produced conflicting answers.

AOD with 2.73's. Installing 3.73's.

93GT...stock 16 inch rims, tires.

What speedo gear. What is this business of 7 or 8 tooth drives? Which drive do I have?

Sorry for the amateur hour questions...but there are so many conflicting opinions on this topic.

Many thanks for your assistance.

 

[willys1]

I have a 93,and whatever the stock gear is Youll need a 23 toothed speedo gear,I have an aod,and 373's.My speedo's rite on the money

 

[87gtconv]

I would say you have a 7 teeth drive gear and need a 20 teeth driven gear. What you can do is remove the extension housing and count them. Remember it is a big job to change the drive gear on automatics! Formula for driven gear teeth is: drive gear teeth X Axle ratio X tire rev per mi all divided by 1000. In your case the tire revs should be about 757/mi! What the formula boild down to is that if you have a 7 teeth gear you need a 20 teeth (orange) driven gear and if you have an 8 teeth gear you need a 23 teeth driven gear!

 

[sn9550]

FWIW I have the purple speedo gear in mine which I believe is the 23 tooth.

 

[davs5.0]

I've been told on several occasions that the late 90's and up cars had the 8 tooth drive gear. you'll need the 23 to get it in the ballpark.