4406 speedo issues

[DJRockit69]

Hey everyone
I just completed my 4406 swap last weekend and on my way to work the next day I noticed my Speedo is off by 2 mph. Now I'm using a 21 tooth gear in the transfer case. I did some playing around with a 18 and 19 tooth gear and it was way off. Now my question is what do I do when I put my 31 inch tires on? That will throw off my Speedo when I do that I was thinking about getting the Jet accu speed #50109 to correct that has anyone used one of them before and how well does it work?

 

[bronchole]

Not sure about the Jet Accu but I do know that if you cannot achieve the desired calibration with just changing the speedo gear you can change the drive gear on the output shaft of the T-case. The drive gears from a NP208 work. I have done this!

 

[albi1cnobi1]

I use the Accuspeed. I went to 32's and changed my gearing. On the 98-01's there is no speedo gear so that was my only option. I've had it for about a year now and no issues whatsoever. Speedo is dead on.

 

[DJRockit69]

Mine is a 96 that uses Speedo gears. How much did Ur Accuspeed run u?

 

[albi1cnobi1]

I bought mine from a member here on the forum for $75.

 

[DJRockit69]

Ok so if I where to change the gear on the tail shaft witnoone from a np 208 how many teeth would I need to match what the explorers have factory?

 

[FIND]

Wait 2mph off at what speed? The difference in your speedo between a brand new set of tires and an old set of tires can be op to 2mph at highway speeds depending on the tires you are running. So it's not that far off if you are talking 65mph and nothing you'd be able to correct with a different gear, but if you are 2mph off at 20mph, then you have room to correct it with a different speedo gear.

 

[DJRockit69]

2 mph fast at 55 with a new set of 235/75/15 I need a 22 tooth gear due to the 4406 swap I did which they don't make plus I won't be able to correct to Speedo when I put my summer tires on which are 31x10.5/15

 

[DJRockit69]

The lower the amount of teeth the Speedo gear has the fast my Speedo reads and the more it's off