Does it affect a truck with an exciter gear and speed sensor the same was as one using the traditional gear and cable? This is my first experience lifting a truck with the exciter gear set-up and am curious. If it does, as I suspect, is there any way to figure out how much it is off?

 

Yes, it does. What year are we talking about? '92 and later are electronic speedos, and can be adjusted easily. Earlier need a speedo cable gear change.

 

Yea but you can correct for it keep in mind however number of times it can be done is limited.

Programing for tire size,

Locate the connector at the bottom of the instrument panel below the center of the glove box. Should be LB/Y, has "PSOM" printed on the connector in white lettering. Held in place with a plastic retainer.

Insert a jumper wire or alligator clip in service wire and clip other end to vehicle ground with the key in the OFF position.

Turn key to RUN while holding down the trip odometer RESET button on the speedometer.
Release RESET button The Speedometer will prove out(sweep across dial and back). The English/Metric and revision levels will be displayed. The last number of the display id the dealer mode lockout count. This count shows the number of allowable conversion constant changes remaining. When the count is zero (0), no additional changes can be made to this instrument cluster. If a revisions required a service instrument cluster must be ordered.
Press and release RESET button again and PSOM conversion constant without the decimal point will be displayed followed by the word CAL.

Press and release the odometer SELECT button as many times as necessary to change the conversion constant to the correct value. The constant will only increase (not decrease) when the SELECT button is pressed so reducing the constant means counting up until the constant jumps to the bottom of the scale and begins counting up from there.

Pressing and releasing the RESET button to lock in the new conversion constant reduces the number of times the PSOM can be reprogrammed by one count. If you change your mind and want to go back to the old conversion constant, turn the key OFF BEFORE you lock in the new constant.

You should be able to get your tires conversion constant from the manufactures web site.

 

Thanks guys, I did forget to state its a 93 with the electronic speedometer. I had planned on driving with the needle on 50 instead of 55-60.

 

I've been meaning to do this for over a year. I may go out and do it tomorrow.

 

Yea gathered that from your first post, the above is instructions how to reset for tire size.

Why not take a minute and correct it so your odometer and speedometer read right?

With a manual trans not as big a deal but if running the E4OD it will effect shift points and not for the better especially if tires are several sizes larger (taller) than stock setting.

You can verify number of changes can be made, hold in odometer "reset" button and turn key to "run" left off button. last number represents number of times it can be changed, 6 means it has never been changed still configured for stock tire size, to exit turn off the key.

It'll look something like "xxx 08 06" (xx = I don't recall what if anything comes before those, first is revision number? the 08 part, the "06" shows six changes are allowed. Each change locked in will drop that number by 1 until none are left.

 

I had intended on doing it that way because I was unaware there was a way to change the reading.

 

The only thing that's stopped me is the wire part, I don't know where that part is our how to connect it.

 

Yea I see the word "had" in your sentence reading it again, didn't click when I read it first time through no idea why.

sorry bout that

 

Under the glove box door and just behind the lower edge of the dash.

Not behind the glove box itself no its under its door and right behind the narrow section of dash that runs across below it.

 

No harm, no foul my friend.

 

Update: I have tried this several times since the original posting, with no luck at all. I have no trouble getting to the point where the value can be changed, but it will not change. The display indicates it has never been changed, so it is probably something I'm doing. Have tried grounding the PSOM several different places close to the connector. Should I try grounding it somewhere else, maybe to the battery ground?

 

If the CAL number will not change it sounds like someone has tied the hot at all times wire and the hot in run wire together at the PSOM. The hot at all times must remain hot when the Ignition switch is turned off or the PSOM will not update the EEPROM on its board.

 

I have used the attached once or twice without problems.

 

^Thats the method I've tried every time with no luck. I will look it over and see if any wires have been spliced together.