Speedometer gear

[88 Red Ranger]

My speedo is reading very slow. 88 4x4 manual trans manual tcase ext cab 2.9l 235/75r15. When we bought the truck the speedo did not work because the gear on the cable was missing. Because of the tire size, I grabbed the gear from the speedo cable at the tcase from a full size bronco. It was Yellow. I did not check to see what axle ratio I had before I did this. I THINK it is stock, but the axle tags are not on the axles anymore. The drivers door was changed before me, so the door tag information is not correct.
Now the speedo is reading slow. At 60, the GPS says I am going 68. Where can I buy speedo gears and I would I know what one to buy?
Thank you for your help.

 

[chrwilkins30]

try lmc. or see which gear ratio you have and head to the JY and get the right one.