Auto to Manual Conversion speedo problem

[jpeterson]

I'm posting this for a friend.



He has mostly completed a auto to manual transmission swap in his '93 (the manual is from another first gen). The only problem he had is the speedo now reads close to 40% high (when he's going 55 it reads 90). The manual transmission has a speed sensor and he has tried different gears but this is as close as he can get. What do you guys do with big tires and/or gear swaps to get the speedo to read correctly, does the Abbott box work with this transmission.



Thanks

Jeremy



'02 Black HO/6speed

 

[Extreme1]

Sounds like he needs to change the gear on the output shaft or change the speedo head. Another alternative would be to take the speedo to a shop and have it recalibrated.

 

[jpeterson]

It apparently has two different speed sensors on it, one is a true electric speed sensor the other one has a gear that he has tried changing but the biggest he can fit is a 30 tooth. He was hoping there was something he missed when he did the swap that he could change. He will probably take it to a speedo shop.



thanks

jeremy

 

[Harlan]

We have a speedo shop here in Reno . take the truck in to a good speedo shop and they will run it on a masured mile and build a speedo chang gear box that bolts to the trans in the same place your speedo cable goes and you bolt you pulse sender to that. Last one I bought was $42. 00. This is the way we change speedo when you change gearing on the big trucks and how I changed speed calabrations when I went from 4. 11 to 3. 08 works very well.

Harlan

Ps: the gear is installed in the tail shaft of the trans and turns the Elec. pulse generater for the Elec part of the operation at the speedo head.