Odometer question

[Explosia]

My odometer is off, can I fix this with Insite? Or is it done through the BCM?

[Chamberpains]

You can offset it with Insite. It is mileage offset under feature and parameters.
As far as what caused the odometer to be off you may want to make sure you have the correct tire size set while your hooked up. That'll be under rev's per mile according to your tire size, make and manufacturer.

[Explosia]

What do mean by offset? Somethings not calibrated, and I was wondering all of the things I needed to check. Tire size, rear ratio etc...

[Chamberpains]

When you have your ECM reprogrammed or you run a different size tire or change gear ratio's that the ECM doesn't know about. The mileage is off on the odometer from what your true mileage is that you have moved. You can "offset" or change the incorrect recorded mileage in the ECM (under parameters using Insite) to match what your true traveled miles are on the odometer.

I've named the 3 big culprits. Reprogramming, tire size and gear ratio changes that will throw off an odometer. The last big 1 is crooked salesman will offset the odometers to show lower mileage.

Figure out what your revolutions per mile is for you current drive tire, get your actual rear differential gear ratio off the tag on the actual rear differential and make sure those numbers match under parameters using Insite. Change them if they are different then what you have on the truck.

[Rawze]

(08-04-2018 )Chamberpains Wrote:  ...
The last big 1 is crooked salesman will offset the odometers to show lower mileage.
...

I have seen this happen. One of the most severe cases is a guy who I helped one time that said he was having nothing but problems with his truck. He then went on to brag that he found an older model truck that only had 89,000 miles on it at one of the big stealershits and the dealer said it was a fluke truck, gave a long story about how it sat and did not get driven, etc. -- It was out in California for around $70k. This guy who had never owned a truck before, had not even driven a truck but a few months, was proud he found such a gem and snatched it up.

I took one look at that truck and you could see that the truck although clean, engine and frame looked like it had been re-painted at close inspection, still looked like it had a whole lot of miles on it by looking at the tiny scratches and tons of wind and road wear in the front bumper, around the mirrors, top, etc. -- I went digging through the ecm and someone had changed the ODO correction on it. The ECM records the transactions every time you connect to it and make a change, when you did the change, and what you did. -- I asked him when he got the truck, and the change happened 2 weeks before the truck was sold to him.

An Internet search for DOT violations on the truck by vin# showed a recorded mileage of 700,000miles+ about 1.5 years before for a headlight being out + a few other citations earlier in its life. -- SAD this guy paid $70k for a truck that had what looked to me like nearly a million miles on it and it was clearly worn slap to the bone. It even had the blo-by of old engine when you took off the oil fill cap.

The guy only got mad at me in disbelief even though his exact vin# came up in the search, he had all the signs + high blo-by etc. He started talking sideways like I had leprosy or something.

About 2 months later he called and apologized saying he confronted the steal;ershit about it and they claimed the eCM was accidentally "swapped" from another truck prior to them getting it. -- It was a lie and I knew it,. the ECM record showed someone changing it.

In the end, they only knocked off some of the price but increased the interest on the truck due to him being late on one payment right after he got the truck. it lead to only about $5,000 on the total cost, and was done simply to to shut the guy up. What a rip-off indeed!.

[Explosia]

My odometer is reading less than a mile after a mile is traveled. Goodyear says my rpm for my brand/size is 508. I look on insite and it has 518 entered. This doesn’t make sense.

Secondly, I bought my truck with 406k on the ecm with the odometer at 344k. So this has been going on for a while. How does the ecm calculate mileage if the settings are incorrect?

*i would like to thank rrod for helping me get insite up and running, dude has been awesome*

[snailexpress]

(08-12-2018 )Explosia Wrote:  My odometer is reading less than a mile after a mile is traveled. Goodyear says my rpm for my brand/size is 508. I look on insite and it has 518 entered. This doesn’t make sense.

Secondly, I bought my truck with 406k on the ecm with the odometer at 344k. So this has been going on for a while. How does the ecm calculate mileage if the settings are incorrect?

*i would like to thank rrod for helping me get insite up and running, dude has been awesome*

In Insite section Features and Parameters you can set parameter mile revolution for tires you have. Also in this section parameter for tire wear calculation to keep odometer correct.
ECM uses speed sensor pulsing, revolution/mile parameter, rear end ratio numbers to calculate speed and distance.

[Explosia]

Ok so my question hasn’t been answered..if my parameter section for rpm is 518 and the correct rpm for my tire is 508, and I change it to 508, wouldn’t that worsen the problem? Or I do I have it backwards?

[bubbanbrenda]

(08-12-2018 )Explosia Wrote:  Ok so my question hasn’t been answered..if my parameter section for rpm is 518 and the correct rpm for my tire is 508, and I change it to 508, wouldn’t that worsen the problem? Or I do I have it backwards?

1 of us has it backwards, lol... probably me. But in my little peanut brain if you are actually covering a mile in 508 rev's and the ECM is counting rev's and looking for 518 revs to make a mile, the ecm thinks you are 10 rev's short of a mile. I don't recall if your original post said how far off your odometer was but doing some hillbilly math I figure your odometer should be about 1/8th of mile short of a mile. Somebody smarter than me needs to jump in here my head is starting to hurt. LOL