Slick 60's

The rearend in my truck is a newer 9'' 28 spline geared to 3.25. I have no idea what was in it before. I need to figure out if i can adjust the speedometer for it or i just have to get a new one.

Correct me if I am wrong members but when you do this can't you just swap out the plastic gear on the end of the speedo cable? Theres a plastic gear on the end that goes into the tranny and you can swap it out for one that has different number of teeth. I got to figure that out also as far as which one to get ,my rear end is different from original.

Yup. . . .it's called a speedometer driven gear & it's sold by ratio in rear.

ergo: Request a speedo driven gear for a 19' whatever year U have with a 3.25:1 rear gear. . . .then install it.

FBp

Thomas, I have several plastic gears laying around. The twist on the gears are differant between a top loader which is what I have, and the automatics/three speeds ( I think ). What transmission do you have?

There are charts on line to figure out what speedo gear you need after changing gears. They are stated in no. of teeth, so the part no. would be T-17 for 17 teeth, for example.

i have the nylon gear i saved from a 3.25 truck.i will see if i can find it.i think its still attached to the cable too.

I recently installed a new C6 in my old bug. Speedo is off by 10mph. It really felt like it was off but to be sure I checked by driving by one of those roadside speed reminders. I was at 30mph and the sign said 41. I had a 17 tooth gear in there so I tried a 20 tooth and its off more now. I will try gears with fewer teeth until I get closer. Any one have a 14 or so tooth gear to swap?

thanks for all the info guys i will check into it. I have a C6 behind a 302 and the orginal speedometer.


Also my compliments to all the members on here everyone is a huge help!
This has to be the best forum ive ever been apart of.

-Thomas

William, like I said above there are many charts on line to help you find the right gear. Work smarter not harder! Here are a couple examples:
http://www.sccoa.com/faq/speedgr.html

http://www.mattsoldcars.com/techinfo/gearteeth.shtml

Oh, and I forgot about the color coding on the gears. I think they're all like that, not sure though.

Here's another. Disregard the fact that it's a Chevelle site:
http://www.chevelles.com/shop/speedo.html