Cascade Crew

MrMike98 · Member Joined: 18 May 2010 Posts: 231 Location: Bremerton

for 1990-1992 with electronic speedo- after a rear gear swap can u reprogram the computer to compensate for the different gears???
or do i have to do gears in tranny also??

Al Hasse · Posted: Sun Jan 27, 2013 3:25 pm Post subject:

What ratio are you going to/from? You may only have to change the driven gear.

I bought the gears I needed from this site

http://www.transmissioncenter.net/

Their index of gears is here...

http://www.transmissioncenter.net/speedometer_calibration_______va.htm

They also have a calculator to figure which gears you should need

http://www.bgsoflex.com/speedo1.html

aaron_sK · Posted: Sun Jan 27, 2013 4:01 pm Post subject:

That calculator is very useful. Use it to work backwards from what you had previously and then you can easily find out what you need.

Transmission Center is retardedly overpriced. They wanted $13 plus shipping for a gear for the transfer case in my Ford truck. Titus Will in Tacoma had one is stock for seven bucks.

Once you figure out what gear you need give the local dealers a try.

MrMike98 · Member Joined: 18 May 2010 Posts: 231 Location: Bremerton

currently with 245-50/16 and 3.23 - i have 17 drive and 44 driven..
so i figure with 3.42 's i would use 15-41 ????

wait.....in tuner cats there is "road speed constant" now set at 4007

so i will set this to 4243..323/342=.9444/4007=4243..
will this calibrate speedo and computer?????????

please correct me if i am wrong...
thanks

Al Hasse · Posted: Mon Jan 28, 2013 3:07 pm Post subject:

If you're able to compensate in the ECM with electronic speedo, in theory, you should be good. My 92's electronic speedo gets its input from the ECM (VSS is fed directly to ECM), so it stands to reason that a correction to the ECM would also correct the speedo.