TH350 Speedometer Gears - Chevelle Tech
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post #1 of 4 (permalink) Old May 20th, 09, 10:11 AM Thread Starter
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TH350 Speedometer Gears

This is my first TH350 and the speedometer reads way high, like 60 at 45 per Garmin.

Can I just change the driven gear, or do I have to change the drive gear and driven gear?

Where does one buy the gears for this puppy?


66 Malibu Coupe, home rebuilt 350. Took me 39 years to get her!
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post #2 of 4 (permalink) Old May 20th, 09, 10:35 AM
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Re: TH350 Speedometer Gears

First go here to familiarize yourself with what you need.

Then go here to get what you need.

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post #3 of 4 (permalink) Old May 20th, 09, 1:05 PM
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Re: TH350 Speedometer Gears

To slow it down that amount, you could try changing the driven gear 1st, but there are only so many possibilities. You need to remove your gear and count the teeth, I would try one with about 4 teeth more than what you currenty have. If one is not available with this amount, then you will have to change the drive gear, probably with one that has one less tooth than what you have then fine tune from there. But do as Wayne suggests, and use the gear calculator .
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post #4 of 4 (permalink) Old May 20th, 09, 1:36 PM
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Re: TH350 Speedometer Gears

Originally Posted by wayner66 View Post
First go here to familiarize yourself with what you need.

Then go here to get what you need.

What he^^^^^ said
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