I'm haveing a hard time finding it. . .when I wasnt working, or waiting for some equipment to warm up I was searching and couldnt find anything.

however, you could always get yourself a smarty from Mads Electronics, I know it will adjust tire size in more that one way if you catch my drift

 

http://www.obd2allinone.com/yahoo.asp?yid=scan+tool


look @ the bottom of the page... tons of links to scan tool software... I will keep looking for what is needed...


slick!!! look at the bottom of the page and the reference to Labview... my programming language... I could develop my own applications...

http://tunertools.com/prodimages/DrewTech/DrewTech.htm

"Drew Technologies also provides an application programmer interface (DLL) for OEMs, integrators, or end-users to develop their own PassThru (SAE J2534) applications. Create your own applications in LabVIEWâ„¢, C or Visual Basic"

 

the more I think about this, the less likely I think it is to get done... you need to have a programmer. the address space for where the tire size is will be independent for each computer and car so the only way to make that happen is to know where it is in the address space.

that is why the programmers for the trucks are different from year to year.. changes in the program on the PCM...

 

I have an update..I went to another Dodge dealership that I referred a friend to. I talked to the Internet guy and I said, "hey, you still owe me favor for referring my buddy that bought a Dodge RAM". He said, "what can I do for you?" I said i need a little help with the service manager. So we go over and talk with the service manager. I told himI wanted to recalibrate my speedo. He said they could only do it up to a tire size of 285. I said I got 315/70/17. He said I dont think we can do it. Then I said all my buddies (you guys) have done it at their local dealerships. I said you just have to select and advanced feature on the STARscan and plug in the #of rev's per mile (More info I got form you guys). I then said that the 285 number is pre-programmed (more info from you guys). So heasked someone else, and I heard the service manager say, this guy has researched this (thanks to you all). The other guy said it can't be done. So I said, "Can we talk to your tranny guy?" In walks mr. tranny guy. The service manager asked him about it and the tranny guy said, he had not done it buthe thought there was an option in the menu. So the service manager saysbring in your truck( i was at work) and we will figure it out. So I said cool. Theservicemanager says when you come in? I said tomorrow!

So I have an appt. at 10:30 am.

I will take mental notesof what they do and how they do,and post it here so the nextpersoncan tell their Dodge place what to do. If anything, you will sound like you know what your talking about and hopefully it will be easier....

I already have a BDTD and dont want to spend more money on another programmer if I dont have to......

 

good work John. . .keep us up to date

 

you are the man. if you can post up what they do maybe then i will be able to convince the dealership here that it can be done. definately keep us up to date on how it goes for you.

 

right on, hopefully, they will set you up without any further hassles...

 

Okay here is the lastest.....
I went to the dealership this morning met with the service manager, he brought my truck right in and took the tranny guy off another job to work on it (so now I am feeling good). The guy hooked up the machine into my truck and walked over to another computer, the STARscan unit is wireless. He want into a menu, then went into a tire size menu and pulled up a list of pre-programmed tires sizes. He went all through the program trying to find a custom menu to that would allow him to enter the number of tires revs but he could not find anything. He then wrote down several tires sizes in the 20's and 22's they had to see if any of those had a revs/mile similar to my tires. Unfortunately nothing was close. So he selelcted the 285/7017 option for the interim. He said another way would be to change the axle size do a road test and try it that way, but that would take some time and it would be trial and error. I watched him go through the various looking for a way to manual enter my tires size to revs/mile and we/I couldn't figure it out. I asked how did the tire sizes they had pre-programmed get there in the menu. He said it was in the software when the got it. So I did get the 285/70/17 update and while he was there I said, hey can you activate my high idle. He went into another menu, click and a button and said, "Its Done!!" The whole thing took less than 5 minutes. He was more that helpful so I told them I would be back.......

I left and went back to the anotherdealership whose Service Manager did not want to help me. I walked around to the back and found the tranny guy. I said, "Hey, I just came from a dealership and the tranny guy tried to fix my speedo but could not figure it out with the STARscan." I asked him if there wasa special menu he needed to go into and could he show me on their computer then I could go back to the other dealership and show them. The tranny guy said that when they plug the machine into my truck and and selected tire size there should have been a option for "othertire size", thru that you can enter the revs/mile. I said that"other tire size" was not listed, bceause I was standing there when he did it. He said that when my truck was built and originally programmed, that it probably was not put in theat that time. Soaccording tohim my truck was not programmed with that option(kinda of take that with a grain of salt).

So, that is all for now....I am going to reasearch a couple more things and I will let you allknow.

 

Changing the gear ratio in the computer won't change the speedo. The speed is read off of the tone ring in teh rear end. It's attached to the ring gear. The speed that this turns at is directly related to how fast the tires are turning, not how fast the d-shaft is turning. Changing the gear ratio to a different size may make your tranny shift weird, as the computer thinks it's should be turning different RPM's.

The only thing that affects your speedo reading is tire changes. I's not like a Jeep or any other vehicle that reads the speed from the t-case or tranny. Those are affected by tire changes, gear changes, tranny gear changes, everything.

This wireless one that he was using. I've never seen it, so I have no idea what it might have. The one that I have seen was a plug in to the OBDII port. Not sure if it makes a difference, but it may.

 

According to the 2006 Dodge Service Manual, the speed sensor is located in the overdrive gear case, which is right behind the transmission. So if the speed sensor is there, how is it reading "the tone ring in the rear end"?