1990 Speedometer gear swap from 3.54 to my 4.11 ratio truck!

[Erska]

Hey. I have a question what needs an answer quickly because my speedo shows incorrect numbers. I installed Michelin XML 325/85 R16 war tires yesterday and my speedo reads too low now. Of course it does.

I'm just wondering what is the difference between the 3.54 and 4.11 gear ratio speedos? Is it the thing what converts the analog reading to electrical pulses in transfer case tail? is it?

Because I just swapped my transfer case to remanufactured one and I had to take the "converter" off from my old one and put it to new one and I was wondering will my speedo read correctly(I didn't know was it from 3.54 or 4.11 truck). There is just one spiral type gear to the speedo output in transfer case tailshaft. Is it the same in all of these trucks?

So I think my speedo will read correctly if I can get somewhere speedo stuff from 3.54 truck right? Can you guys help me with this? I don't want to buy 300 usd Truespeed boxes if I can do it this way.

[Tacoclaw]

All the gearing is handled in that little plastic piece with the wires coming out of it. If you put your old one back on your speedo will still read the same as it did before. It will be wrong, due to those tires, but it will be the same wrong as it was with the old x-fer case.

If you're asking if a 3.54 converter will make your speedo read correctly with those tires and 4.10 gears, I don't know. I suck at math.

However, all you need to do is grab that little gearbox with the wires on it from a 3.54 truck nothing internal to the x-fer case has to change.

[Erska]

However, all you need to do is grab that little gearbox with the wires on it from a 3.54 truck nothing internal to the x-fer case has to change.

Thank you!!! That is all I wanted to hear! Now, where do I find one!?

[Erska]

Yes! After a long Googling I think I found a site for me!

Check it out!

http://www.transmissioncenter.org/speed ... ousing.htm

I think that "#54RA2" Should work for me! And they even ship internationally. Yes!