Stratus R/T - MPH higher than clocked/Odo higher than driven

midge314

I purchased my 2002 Stratus R/T 3 days ago. The dealership was over 100 miles from my home. On the drive home I noticed that my odometer was adding more miles then what the mile markers were saying I was driving; about 1/10 mile per 3 miles driven. My husband, who had just purchased a 2003 Dodge Dakota 2 weeks before, and I decided to make a test drive to see exactly what was happening. His truck adds miles properly as per miles accumulated based on the highway mile markers. We both drove our cars, with him following me, and I set my cruise control dead center on the 60MPH mark. While he was following me, my husband's speedometer said he was traveling 56MPH. Also it took me 63 seconds to travel from mile marker to the next mile marker. The trip was over twenty miles. In the end, his trip showed his truck traveling 24.5 miles whereas the Stratus showed a trip of 25.3 miles. I took it to the dealership who test drove it by stop watch & by the mile marker method but said they cannot reproduce the problem so are not sure what they can do about it. Are there any suggestions as to how to solve this issue and get my vehicle fixed under warranty?

zueslewis

could be off a little and there is absolutely no way they would match exactly. Even the "calibrated" police car speedometers were tested and shown to be off by 2-3 mph at 60, which would, of course, affect mileage driven and shown.

I would recommend a much longer drive to determine fault, but DO NOT use the mile marker system as it can vary over 100 meters - have another vehicle get involved, drive quite a few miles, logging an exact measurement; then use the Dakota, then the Stratus - only my recommendation.

Bear in mind your car will not measure mileage perfectly due to several reasons, the main one being that your speedo is not a radically calibrated tool. No car's speedo is, unfortunately.

midge314

You are right, it's very possible my husband's dakota could be slightly off, but we did a test on his vehicle and it increased by only one mile from one mile marker to the next, and did this so close to the minute mark at 60MPH it was eerier. And I realize that the markers are not perfectly spaced but in my experience are pretty close to miles driven by most vehicles. I also know the odds that the Dakota trip and the Stratus trip would be identical are as good as an estimate for future cost being exact is, but a .8 mile difference over a 25 mile trip is too big a delta, in my opinion, for there not to be something wrong with one of the vehicles. In my case I believe it's the vehicle that is increasing miles faster than the one that is not. This means for every 30 miles an additional 1 mile will be added to my odometer. And yes this is small but with this happening I'll lose approximatly 2300 miles off my warranty. I'm paying over $900 for their extended warranty. I really want to get the entire miles I am purchasing. Also in the end this will affect the value of my vehicle when I wish to trade it in. I wouldn't be researching this otherwise. I am taking your advice into consideration and hopefully I can find one additional vehicle that will do the same trip.

zueslewis

then go back to the dealer with your info.

jgmilberg

Find out what the original tire size is. It should be on a label on the drivers door. If the tire size on the door do not match the tire size on the car that could be the problem. If the tires are smaller than what Dodge put on the car it will knock off the speedometer and odometer.

midge314

Your answers are appreciated. I just bought this car from the dealer on 11/11/02. Everything is stock as it came from the factory as far as I know. It doesn't appear they made any changes to the vehicle. And yes I have taken it back to the dealer and they said they couldn't reproduce the problem. The mechanic put 60 miles on the car in checking. I can't understand how he couldn't have seen how the odometer is off. I'm going to try another chrysler dealership and see what they come up with. Thanks for writing.

midge314

Hi all, My issue was proven by another dealership. The other dealer did a roadtest today by clocking with stop watch and checking odometer with milemarkers then using a DRB to check the speed. The tech determined that when the Stratus says it is going 60MPH the vehicle is going 58MPH. The thing is they do not know how to fix it. They are going to work with Chrysler headquarters to try to figure it out. At least I now have documentation that there is a problem. Is there anyone out there that might know what fix can be done to solve the problem?

speedshift

There was an article about this in a recent Road & Track. I'm no expert but the 2 mph difference at 60 mph sounds well within the usual tolerance.

As someone here said, speedos aren't precision instruments, I suppose due to cost concerns, but they always read a little high (or a lot high in the case of certain German cars) instead of a little low. I always assumed this was automaker CYA.

I've noticed this whenever I drive past one of those machines the cops park by the side of the road that give you a reading on your speed. Even at 35 or so they're usually a mph or so higher than what the speedo shows.

haspelbein

There is actually a German law that mandates the speedometer reading to never be higher than the actual speed, causing the speedometer to show less than the actual speed in many cars.

However, the odometer is usually correct.

Other than that, I would assume the 2 mph to be an acceptable tolerance.

zueslewis

reprogramming the Body Control Module (BCM) can recalibrate the speedo. That is an acceptable tolerance, though.

speedshift

Sorry, meant to say that the roadside signs always flash a mph slightly *slower* than what my speedo says, even a low speeds where speedo error is minimal.

For some reason this reminds me of a '62 Chevy I had that someone had put 4.11s in without changing the gear in the tranny that drives the speedo. The stock gears had probably been 3.36s or something close. Around town the speedo error wasn't too large but on the freeway an indicated 75 was more like 55 IIRC. Of course with 4.11s you're always in the slow lane. Just thought I'd share.

midge314

The NIST lists an allowable speedometer error limit of 4% and mine is 3%, but the odo is calibrated to the speedo. It is clocking 1 mile for every minute that I drive when it is showing 60MPH when the actual speed is 58MPH. This means it is clocking 2 additional miles for every 60 actually driven. In other words I will lose over 2,000 miles off my 70,000 mile warranty. This is my main concern. So the question is "What is the fix for the odometer?" Any suggestions are appreciated.

zueslewis

"The NIST lists an allowable speedometer error limit of 4% and mine is 3%, but the odo is calibrated to the speedo"

There is no need for repair. Everyone who owns a car deals with this.

tboner

Then you will be "just right"

Really, this might work. If you run something like a 215/55-16 then a 225/55-16 is about 1.7% larger, or even closer to what the speedo reads. So a plus zero tire upgrade would give you a more accurate speedo and perhaps a bit better handling.

However, 3% really is nothing in the grand scheme of things.

Besides, when you calculate MPG, you'll get better numbers this way, LOL.

TB
Thinks this might be a new "conspiracy" to run warranties out 3% sooner, LOL

speedshift

Before you spend any more time on this maybe you need to contact the company underwriting the warranty to see what their position is. (I have a feeling I know.) Maybe there's some fine print in your warranty agreement.

midge314

I'm sorry all I haven't answered this discussion in a couple of weeks. I didn't realize there were any post. So to begin with I'll take this a person at a time.

First off, zueslewis, you are right, in this day and age people have to accept problems and not be satisfied. In fact I found someone with a GPS that shows the Speedometer is showing 3 MPH more than I'm actually driving. That's a 5.2% error, well out of scope of the acceptable limit. Do I now accept the problem?

Now, tboner, I loved your post. I have a 17" wheel but maybe that will help. I'll look into it when I buy my tires maybe even get a 4-5% increase in size.

And finally, speedshift, thx too. Yes there is fine print in the warranty about an inaccurate odometer voiding it, and boy did I have a discussion with one person about this saying just that. The dealerships and shops don't believe what was said when it's a manufacturing defect this is causing the problem.

Anyway things are being worked on and I heard from one of the people I'm dealing with that mine is not the only vehicle seeing this problem. I'm not being provided with the quantity and I'm wondering how many out there have this problem and do not realize it. If it hadn't been for a long drive home I wouldn't have discovered the issue.

Oh well, thanks for listening all. Hope your Thanksgiving was a happy one.