There is no program changes for gears according to the dealership. I installed 3.92 from 3.55 in my 01. In fact I have mine if you need one. Removed at 70K.

 

How does it adjust to the change in gear ratio. Would a simple hand held tuner be able to change it. say on a 96

 

The computer doesn't need any adjustments for the gear ratios. The gear ratios in these trucks are completely independent of the computer.

Just swap out the gears. No need to touch the computer.

 

your axle ratio is either on a sticker in your glove box or as soon as you open your hood look up and see if its there

 

I am assuming that you want to change the settings in the ecm so that you show the correct speed on your speedometer after changing gear ratios. You have a pre obd II vehicle which means that in order to change that setting you would need to speak to someone from a dealer or other competent shop that has that information on how to flash your ecm with the correct information. It is obviously changeable since these trucks came with different ratios in model years. Hope that helps somehow.

 

Mr. eatinchevydumpinford, no offense, but you need to look at the dates of the threads. This thread has been done for over a month. I highly doubt the OP has been back since, otherwise he would have posted.

Second, I'm by no means an expert, but I don't believe our sensors/computers need any recalibrating for different gear ratios. Different sized tires, yes, different gear ratios, no. I'm not sure on the specifics, but thats how it was explained to me. Someone correct me if I'm mistaken.

 

Where is the speed sensor? On my Dakota it's in the transfercase. Unless it's on the ring gear or wheels, the speedometer will read faster with lower gears and slower with higher gears. Different gears (unless the speed sensor is located on the ring gear or at the wheels as previously mentioned) will throw off the speedometer just like different sized tires. You're changing the amount of revolutions it takes to drive a certain distance.

 

IIRC, I believe it is located on the rear axle. The ring gear sounds right, but don't quote me on that.

 

i had that same thought when i looked at the date of the original thread. i doubt this guy has had his truck sitting for 2 months waiting to see what everyone has to say.
i would think that changing the gears would have a similar impact on the speedo as larger/smaller tires just because its either more or less revolutions of the drive shaft depending on which ones you get, but they wouldn't be huge differences, just a little less or a little more power and maybe 1/2 mile off on the speedo. but i'm no expert so don't burn me up if i'm wrong, i'm just giving my opinion.
how come every time someone asks about gear ratios, somone mentions the sticker on the bottom of the hood but no one ever mentions the sticker on top of the axle tube next to the leaf springs?

 

Speedometers are off by a percentage. If you put on tires that are 10% bigger or gears that are 10% higher, your speedometer is 10% slow, so at 30MPH you're actually doing 33 and at 70 MPH you're actually doing 77, ect.

I've had a speedometer that was 25% off before in my B2 from a combination of gear change, tire change and transfercase change (different speedo drive gear in the t-case).