Speedometer Re-calibration

[pwknapp]

Anyone know where I can get the NV4500 gears to reset my speedometer other than a dealer? I've got a '96 truck with some 36" tires and want to be able to drive it without using my GPS. Also the wife drives it once in a while and says she is sure she is going faster than the 65mph on the gauge.



Thanks, Paul

 

[Bob4x4]

They go in the transfer case in a 4x4 Anybody who does trans or transfercase work should be able to help you out.



Bob

 

[biggy238]

An offroad shop but they are only $30-40 at the dealer. I think you will be pushing your limits with the gear though because they only go down so many teeth. I think mine has 27-26 teeth and is off by 1mph at 60 with 3. 55's and 35 inch tires.

 

[biggy238]

My Post from early this year:





The PCMs only allow for stock tire sizes on the 95 trucks. (mine has a 95 prom woo hoo)



If you want to do it yourself the part number is 520676XX



The XX needs to be replaced with the number of Teeth you will need on the Gear.



I think Mine had 245/75's stock (they weren't on there when I bought it so i'm guessing) with 3. 55 gear ratio and a 31 tooth gear. I put a 28 tooth (52067628)

and my speedometer shows 56. 0000 (whatever) when the van showed 55. I need to GPS mine too.



Keep in mind the gears will only have even numbers of teeth. When you put the gear in, the VSS has number ranges on the side. One is 26-31 (teeth) the other is 32-35 I think. The number range that your gear falls between will require you to put that number range at the 6 O'Clock position (down) when you install the VSS. The unit has a retainer (looks like a chevy distributer hold down) with a nut on the Transfer case (I think it's 10mm-there's another on the VSS-don't remove it) and the unit just pops out after disconnecting the wires. The gear should slide off a square axle and the other will slide in until it bottoms on the plastic. Clean the seals, replace them if needed, clean the T-case mouth and apply some transmission fluid to the gear and seals. Reinstall it and clean the plug before reassembling.



Sorry I don't have pics, I wasn't thinking.

 

[pwknapp]

Thanks for the replies. Called a few shops and dealers in Salt Lake and they could'nt help. I'll still look for someone who can guess better at which gear to buy with the 305/85's vs the stock 215/85's.

 

[SBettencourt]

Paul,

What rear gear do you have? It's not difficult to figure out what speedo gear you need. I have a calculation at work that comes out pretty close. There used to be a speedo gear calculator on a Jeep website but it is gone now.

The gear is about $13 to $24 from the dealer depending on the gear count. Use the PN format Biggy posted. You can also order from an online source like dodgeparts. cc but its just as easy to go to the dealer.

Found a link to a speedo gear recal page. Jeeptech page

 

[WDixon27]

heres my favorite number cruncher

http://www.bncoffroad.com/tire_gear_cal.html