speedo help

[scotts90ranger]

I just swapped out my whole drivetrain except the engine and transmission, my speedo is WAY off. It was close with the 31's and 4.10's with the white gear in the transfer case but is reading fast now.

Current setup:
35" tires, 5.13 gears, manual 1354 with red gear in case, pink gear on speedo cable.

looking at the tech library I have a 19 tooth gear on the speedo cable, the table only shows up to 21 tooth gears, are there gears with more teeth available? going from 19 to 21 is only a 10% change when I think I need about 30% which would mean 24 or 25.

any ideas? or should i rip apart the transfer cases to swap the gears...

 

[4x4junkie]

21T is biggest for the cable.

I have the 21T speedo gear in mine and it's about 3 MPH fast at 60 (or about 5% off) with 35s. I THINK I have the white worm gear in the t-case though (whichever one is stock in a 1354 in a 4.0L truck, which is the "faster" of the two).

My BII's 1350 on the other hand had the "slower" (red?) worm gear inside it, and with a 18T Yellow gear, it was only a hair faster than it is now (about 5 off at 60, or about 7%).

I would think with the same (slower) t-case worm gear and maybe a 20 or 21T speedo gear, it should be possible to get it right on.

 

[scotts90ranger]

by eye the red one looked steeper than the white one which would make the speedo faster.

How hard is it to change the gear in the case? just take off the rear flange and split the halves? I should have looked in the other 1354 I have in the garage... might just do that

I need to get the alignment bushings in that I just got so I can drive around a little more and see how far the thing is off...

 

[4x4junkie]

It's been a couple years since I had a t-case apart, but I do seem to recall the speedo gear was right there after you pull the rear half off.

I could be wrong on the worm gear colors, though I know for sure my 1354 case has a "faster" gear in it than my 1350 did (my speedo jumped from 7% fast to like 20% fast simply after the case swap!)

 

[scotts90ranger]

I wish I would have grabbed my other T case when I did my swap... it has a white gear...

I guess it's only ~13 bolts away from being in...