Speedo Info

[CJ007]

I saw some info on here not too long ago, but am hoping someone can give me some specifics. I regeared to 4.56. Have 35's and my transfer is a Dana 300 (2.62). I think original tire size was 28" or 29" on an 83 CJ7 .

I found a calculator on my local site but it came out to 6.6 or something? and it seems most are sold by teeth.

Any help and direction to where I can pick up one up is greatly appreicated!

 

[BusaDave9]

IMHO I think the best most accurate way to figure out how to correct the speedometer is to calculate how far off the speedometer is as a percentage.

One way is to drive past one of those speed limit signs that have a radar displaying your speed. As an example you may find your speedometer is 6% too fast.

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Another way is to test the odometer. It's just as far off as the speedometer. Stop at a mile marker. Write down the mile marker and odometer. Drive 10 miles and check the odometer again. Figure out how far off your odometer is as a percentage.

Next you have to correct your speedometer. The speedometer cable goes into the rear output shaft of the TCase. On the right side of this picture.

Unscrew the cable. There is a speedometer gear in the tailhousing where the cable went in. Remove the bolt and take out the gear. Count the number of teeth on your gear. If your speedometer is 6% too fast then you need a new speedometer gear that has 6% more teeth. If it is too slow then you need less teeth.

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[JR74CJ5]

I just downloaded a gps speedometer app for my iphone but my speedo is toast so just needed something... Tested and its pretty accurate and its free

I know may not be helpful, but since runs on "gps" ( kinda ) it doesmt matter gearing, or tire size...

 

[CJ007]

IMHO I think the best most accurate way to figure out how to correct the speedometer is to calculate how far off the speedometer is as a percentage.

Thanks

I was showing 45 and sign said 33. So roughly 7%. Anyone know where to pick one up at a reasonable price?

 

[BusaDave9]

Try these guys:
Speedometer Gears for Dodge and Jeep, Gear . . . . .
Near the top of the page is the Jeep speedometer gears.