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**pjmoreland** · 03-08-2006, 04:00 PM

The TCI website indicates that your tire diameter is 29.74". TCI also indicates that with a 15-tooth driving gear, you'd need a 41.765 driven gear, so A 15-tooth (gray) driving gear and a 42-tooth (green) driven gear is the closest you'll get. You'll also need the driven gear housing for 40-45 tooth gears if you don't already have that one.

Here are the GM part numbers:

15-tooth (gray) driving gear = 8642620 (TCI 880018)
42-tooth (green) driven gear = 1362049 (TCI 880030)
40-45 Housing = 25512339 (TCI 880023)

If your housing has 40 41 42 43 on the side of it, then it should work fine.

03-08-2006, 04:00 PM	#8
pjmoreland Senior Member Join Date: Jan 2005 Location: CA Posts: 6,241	Re: 700r4 Speedometer with 20's The TCI website indicates that your tire diameter is 29.74". TCI also indicates that with a 15-tooth driving gear, you'd need a 41.765 driven gear, so A 15-tooth (gray) driving gear and a 42-tooth (green) driven gear is the closest you'll get. You'll also need the driven gear housing for 40-45 tooth gears if you don't already have that one. Here are the GM part numbers: 15-tooth (gray) driving gear = 8642620 (TCI 880018) 42-tooth (green) driven gear = 1362049 (TCI 880030) 40-45 Housing = 25512339 (TCI 880023) If your housing has 40 41 42 43 on the side of it, then it should work fine. Last edited by pjmoreland; 03-08-2006 at 04:02 PM.