ThumperPup

ok i was misstyped when i said 11 miles for every 1 i mean 11 for every 10
when i drive 10 miles and iv got past 11 mile markers or close to 11 mile markers something is wrong there with that

ok well ill let you know what the dealer says id rather find out and know for sure id rather over react than under react
at times

sometimes not good but sometimes not bad to overact about things

LexBob2

Although I've never given it much thought, I've never received a ticket where it was my speedo's fault for an inaccurate reading that didn't match up with the officer's. .

ThumperPup

I wanted to get an opinion from my old Mechanic up in Ohio
so i called him today hes one of the smartest ones i know lol really good guy

i called him and told him what was going on and asked him what he thought
first he asked
tire size proper oem tires proper tire pressure and all i said yes

then he asked how worn they where probably down to 1/4 of the original tread
he said that most likely my issue right there

so next month ill pick up some new tires
and see what it does then if it still happens then ill have it looked at


thinking of going with the same tires on there now witch are the Bridge stone Turanza

but i also have been partial to Michaline over the years usualy all i get
so i am also thinking about the Primacy MXV4 perhaps

jcat_350

There's no way that being down to 1/4 tread on your tire causes a 10% difference in odometer reading. I think your mechanic needs to recertify.

The diameter difference and speedometer difference are almost proportional to each other. That means your diameter would also have to be 10% smaller than stock, which would amount to approximately 3".

All season car tires do not come with 3" of tread.

ThumperPup

well i know i need tires anways because these look to be worn down and not even either also look to be cracking in places probably the oriainal 6 year old tires
so ill see ill have them replaced and then see what goes on
he said its propbably it and i trust him and if its not than its not

so im not even going to worry about it till i gete new tires

and then if its doing the same thing ill be back in here saying how im going to the dealer to have them check it and
im sure most of you who have already said it's normal will be saying the same things you telling me now that not even to worry about it

jcat_350

I'm sure the dealership will be glad to diagnose your car as many times as you'd like to bring it to them and pay them for it.

ThumperPup

no actually not im not going to say exactly what but i know what it would have cost or i should say what it would have not cost

not every dealer is out to rob you
i have found a few dealers over the years that a really nice and some who i wouldn't trust holding a thread i yank from a part of clothing

LexBob2

If you are out of warranty, nearly every dealer, nice or not, will charge for the diagnosis. It might not hurt to call first and a get ballpark estimate for it and then you can determine if it's worth it.

ThumperPup

maybe i miss said what i said above or you perhaps misread what i said above but
i already know how much it is or well i should say won't cost me

as in you get it ? it's not going to cost me a dime ?

hmm ok i said i just said it

an i do have a warranty on the vehicle

it's an 07 with 46k on it
and it has a full warranty

jcat_350

Well if that's the case good luck. At 6 years old it's not the original factory warranty. I believe you recently bought this so it's not certified. Aftermarket warranties don't typically cover dealer diagnostic fees.

I would also think that whatever dealer (particularly if it's a Lexus dealer) you bought it from, would extend a couple diags for you as a courtesy. It seems as if you've had serious doubts about your car since purchase so I only hope you didn't use those up in the same fashion as we've seen on here.

Bottom line is this, I'll spell it flat out so you understand where we're coming from.

If your car was registering 1.1 miles for ever 1 mile driven, that's a 10% difference. The odo/tripometer register distance regardless of speed.

That means your speedo should be off by 2mph at 20, 4mph at 40, and 8mph at 80. You said your trusted mechanic pointed toward your tires only having 25% tread left. As I said, this would require a 2.6" difference in overall outside diameter of wheel and tire from where it started, or about 3.5" of tread overall. I don't even know of any off-road truck tires aside from 40" mud boggers that have treadblocks that tall over the flat of the tire.

You said the car is 2mph off all the way across. That right away should tell you it's not due to anything in the drivetrain, but rather in the speedometer itself, as multiple members have told you they've observed on their cars as well.

You also said you're measuring this by GPS. Do you know the error tolerance of the GPS system you're using? Reason being, most recently made units get you within about 30 meters (~100ft) of your destination. Some more accurate ones get within 30 feet of your destination. The difference of .1mi you're talking about is 528 feet.

If our tripometers (i assume that's what you're using due to the decimal point you report) display 1.1 as a rounded number (as in once it passes 1.06 would round to 1.1) and your GPS doesn't display it until say 1.095, you have a degree of error in between the 1.06 and 1.095 where the GPS would read 1 mile, but the tripometer reads 1.1.

You mentioned that you drive past 11 mile markers in 10 miles. Easy explanation for that. Mile markers don't start counting 1-10, which would be 10 mile markers (1,2,3,4,5,6,7,8,9,10). The first mile marker starts from 0, adding another mile marker to the group (0,1,2,3,4,5,6,7,8,9,10). This is of no consequence to the issue you think you're having.

I hope that helps explain it, at least from where I'm coming from and I know some of the other members are coming form the same place as well. I wish you luck, but would caution you that even if the dealer is doing courtesy diags right now, that may not always last.

ThumperPup

thanks the mile marker the way you explained it going from 0-to 10 helps me understand that better

also the warranty that i have we have on other cars and never an issue
Aslong as its a item that they cover then they cover the diag charge also

100 Deductable is what i would pay on any visit i have had some visits where i pay 100 and the warranty company has had to fix 4 items at once

and another few times where i have had 100 deducables and only 1 item wrong
it's 100 per visit
and it includes Diag fees

i don't think i have ever heard of a company that doesn't reimburse or cover diag fees aslong as its a covered issue

also this dealer was not going to charge me the diag fee at all and he was also going to fill my tank up for free since they forgot to call and tell me the other day when i came in on Monday that there tech was out sick as an apology 70 bucks in free gas

also the car is 5 years and 4 months from the In Service first reported date of purchase
it still has the factory Drive triain warranty on it
that they also already fixed a axle no issues on that

all in all im happy with the car im happy with the warranty company i use witch is threw Santander usa its the S-gaurd warranty
i am one who used to be against warranty years and years ago when they where not from the factory because they never paid out on anything usually but the past 6 years i have been getting these warranty and have not had issues with them

from Santander from Wynns and from warranty's direct

jcat_350

I think you missed the point of my entire post. Good luck with your car.

SW17LS

Bottom line...if you go to the dealer and they do a diagnostic, they will charge you for the diagnostic. Its not about "robbing" you, its about a business charging customers for their service. People don't provide service for free. Your warranty will pay the diagnostic fee and the repair, less your deductible if its a warrantied repair. If there is no repair, they won't pay anything. I'm telling ya, the dealership will return your car and say its operating as designed and give you a bill for $120.

Your GPS, and certainly not a GPS phone app, will not provide you with an accurate speed or distance reading. These things are seldom exact, even highway mile markers outside of the logical post jcat made above that might explain your discrepancy. We've given you a lot of ideas how to try and determine whether or not there is an atypical issue, and you don't seem interested in doing that.

You have an incredible amount of knowledge on this vehicle here in this forum. There are members here like me who have driven this car for hundreds of thousands of miles, you have people who have done a ton of their own maintenance on them, rebuilt suspensions, etc. If one doesn't want to follow any of the guidance or recommendations put forth on the forum...I'm not sure what the benefit to being here is.

ThumperPup

it just seemed like i was getting mixed msg i guess because some of you said it was not normal and some said it was then some said that it was probably done on purpose to take miles away so warranty runs faster

so i guess when i get and 3 reasponses and first seems like you are all saying its normal but they did it on purpose to make miles go faster then i have some saying its not normal
well if you where me what would you do

ever try to tell a dog up down at the same exact time and see what it does ?

SW17LS

Its normal...and the purpose is not to make miles go faster. You also don't know that any difference in actual speed vs displayed speed on the speedometer translates into the odometer being inaccurate...as I and others have said.

I just looked back through the thread, everybody has said it was normal, nobody said it wasn't normal.
This is also a scenario where searching the forums will help you, because there are many threads on this topic on here.