i need help with finding a new speed sensor.... i am putting a 4'' suspension lift and 33X10.50 tires on my '88 4X4 extra cab pickup ........ my dad says that having the lift without a new speed sensor will throw off my odometer and screw stuff up so i need to find one ......HELP please

 

PPPPLLLLLEEEEAAAASSSSEEEEE i need help ASAP

 

The real answer is to regear the axles for the taller tires. With a 5 speed tranny, 4.88s are just the ticket, with an automatic, 5.29s.

Likely with an '88, you have a mechanical speedometer, so the only other option is to get a ratio converter box froma speedometer shop. I used to run one and it cost about $100.

Also, don't need anywhere near 4" of lift for those tires:
- http://www.4crawler.com/4x4/ForSale/...it.shtml#FAQ10

With the money you save on the lift, you can probably do the gears.

 

where does the ratio converter box mount?

 

Into the back end of the transfer case where the speedo cable attaches. Basically it is a little gear box, has a female metric speedo cable end that screws into the t-case and amale metric speedo cable end that the speedo cable screws onto. You run a calibration test for the odo and speedo to get the actual error in reading (with the new tires) and send that to the shop and then they make the box. I got mine about 10 years ago from NWOR, but they sent it out to some shop to make the box, so likely most any speedometer shop can do that. Also, there is nothing on these trucks that will get "messed up" if you don't recal the speedo, aside from the speedo and odo reading slow. You will lose driveability and probably gas mileage if you don't regear.

 

Who cares!!!

your speedo will be off by maybe 5%, figure it out in your head as you are driving.

Oh and the lift has nothing to do with the speedo its the larger tires. To determine the difference use this formula (new size - orignial size = X ) then (X/original tire size = percentage that the speedo will be off.)

 

Assuming 28" stockers and going to 33s, you'll see about a 17%-18% error in the speedo (it'll read slower than you are actually going), so at an indicated 60, you'll be going nearly 71. Same on the odo, it'll under report distance traveled by the same factor.