More speedometer gear questions

[liquidfluidity]

So finally got my spare axles in and have some questions about speedo gears. I'm running MT/R 33s and have a 3.73 gear ratio.

Questions:

I have the 231 transfer case and the 3 speed auto 2002 Sport, 30/35 axles

1. Do I need the short or long shaft gear?
2. Different sites show the use of a 30 or 31 gear tooth - which is correct?

I haven't measured true tire height yet but have seen many posts regarding the MT/Rs to be pretty accurate and only 1/2" short of advertised height.

Please share your thoughts and experience, guys

 

[pagrey]

Those gears are expensive, don't guess. Measure your speed with GPS and compare it to your speedometer. Take out your gear and count the teeth. Do the math and buy the correct gear. If you need help after you take some measurements just post back. I'm sure somebody will help out.

 

[liquidfluidity]

Thanks, I'll check speed vs mph using GPS on my way home from work. I have an app installed that I totally forgot about. Where is the info on doing the math to figure out what number of teeth you need for the closest mph reading located?

 

[Chris]

Or just get a speedo healer

https://rover.ebay.com/rover/1/711-...0001&campid=5337789113&icep_item=274046516383

More expensive, but oh so painless and easy

 

[liquidfluidity]

I wondered about that but have yet to look into them. How accurate are they and is the only thing that makes them vehicle specific, the loom that it attaches to the vehicle with? I guess my question is - can this be used on different cars with the purchase of the correct connection loom?

Like I said, I haven't read on them yet but that price would be easier to swallow if the purchase of a different loom would make it compatible with something else

 

[pagrey]

Thanks, I'll check speed vs mph using GPS on my way home from work. I have an app installed that I totally forgot about. Where is the info on doing the math to figure out what number of teeth you need for the closest mph reading located?

Speedo-math

 

[liquidfluidity]

Thanks!

 

[tworley]

I wondered about that but have yet to look into them. How accurate are they and is the only thing that makes them vehicle specific, the loom that it attaches to the vehicle with? I guess my question is - can this be used on different cars with the purchase of the correct connection loom?

Like I said, I haven't read on them yet but that price would be easier to swallow if the purchase of a different loom would make it compatible with something else

They can be wired differently for different vehicles. There is a how-to on here that shows some members buying a used speedo healer from a motorcycle and changing plugs to fit their TJ. @rasband , off the top of my head, has done it. Mine is less than a 1/2 mph off according to my GPS.

 

[pagrey]

Here it is:

How-to make a speedohealer harness

 

[freedom_in_4low]

when I knew my build was going to involve both a gear change AND a tire change at different times, rather than buying a new gear twice I went with the speedo healer. It's been great.

 

[rasband]

They can be wired differently for different vehicles. There is a how-to on here that shows some members buying a used speedo healer from a motorcycle and changing plugs to fit their TJ. @rasband , off the top of my head, has done it. Mine is less than a 1/2 mph off according to my GPS.

Yep, easy install and under $100 if you find a beat up speedohealer from a bike. The flexibility to correct over time as other moving parts are at play (Tire and gear changes) are great and in the mean time you don’t throw off the clock.

 

[pagrey]

They are always on ebay cheap, one right now for $40 shipped. If you hard wired it with some waterproof connectors you'd be done for under $50.

 

[rasband]

They are always on ebay cheap, one right now for $40 shipped. If you hard wired it with some waterproof connectors you'd be done for under $50.

Even better! The cheapest I found when I did mine was $70 and then added the connectors you documented in that other post. At <$50 you're right next to a speedo gear and it's a nobrainer.