So does the wheel speed sensor actually read "wheel speed" (the RPM of the wheel), or does it read the speed of something else and calculate based on engine speed, gearing and OEM tire size? If the sensor reads honest-to-goodness rotational speed of the wheel, then the gearing doesn't effect anything. Velocity = wheel radius x rotational speed, where rotational speed is given in radians per second. One would think the easiest way to do it is measure the wheel speed, then calculate based on tire size. Otherwise, as stated above, things like engine speed and final drive ratio start to cloud the problem.

 

You don't need to recalibrate ANYTHING for gear changes. The tone ring is between the carrier and ring gear. Nothing is neccessary for gear changes, only tire size changes. I know, I went from 3.73 to 4.10.

 

I love my '03 CTD QC SB SRW 4:10 6speed 2WD. It gets an average of 18 mpg and tows great.

OK, it does run out of the sweet spot about 78 mph and it might be nice to have a little less final gear, but I wouldn't want to change the rear, I would rather have one more gear in the trans! Can you get a 7 speed?

I honestly do catch myself reaching for the stick to get one more gear. jim

 

You're right. I stand corrected.

 

How is it possible to find out what ratio a truck has. I looked on the original spec sheet, nothing there.

 

Hi all , I have noticed better milage on turnpike at 70 to75 because i'm now under 2000 when with 4.10 s I was spinning around 2300 0r 2400. I was running 17 or 18 on road now i'm at19 or 20 . The biggest advantage is really the comfort at 75 . The complete job with oem gears was 1350.00. Does anyone know for sure about the calibration. Thanks