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Recently bought my first camaro and the speedometer is off the guy who sold it to me said it could be the tire size but he's not entirely sure. What can I do to fix it?
Last edited by Gman1020; Oct 11, 2016 at 10:33 PM.
Would also be helpful to know the speed that it's off by 5 mph at.
After all, I'm sure it's not off 5 mph while sitting still; off 5 mph at 30 mph; off 5 mph at 70 mph; off 5 mph at 150 mph; etc.
More likely, it's about accurate sitting still, off 2 mph at 30, off 5 mph at 70, and off 10 mph at 15; or some similar pattern. In other words, off by some PERCENTAGE or PROPORTION.
Regardless of those details, the fundamental reason most likely is, the rear gears have been swapped at some point in the car's life, and whoever did it, didn't also swap the speedo gears.
Your not answering the question. Its going 5 mph faster but at what speed? 5mph faster all the time? Or just at 35 mph or at 75 mph. And what speed are you measuring your mph at.
Your not answering the question. Its going 5 mph faster but at what speed? 5mph faster all the time? Or just at 35 mph or at 75 mph. And what speed are you measuring your mph at.
5 mph over all the time like 35 mph in reality is read as 40 on the speedometer
I think I'd be looking at other solutions first..I'm guessing if it's only off by 5 mph, it's probably the tire size, but he hasn't yet told us what size is on the rear of his car.
Take a note pad and make a chart with three columns.
In the first column, list some random but ascending speeds. Like 10-20-30-40mph...etc. up to what ever speed you feel like...145mph? j/k
Leave the middle and third columns blank.
Take your note pad and your GPS with you and go for a drive on a deserted stretch of road.
Drive at a steady speed say 10MPH as indicated on your speedometer. Look at your GPS and note the speed. Write it down in the middle column next to the 10mph. Do this for each speed in the first column.
Now subtract the number in the first column from the number in the second column and put this difference in the third column.
If the numbers in the third column are the same (or pretty close), it's probably a tire diameter issue.
If the numbers start out close to zero and gradually increase, then the problem is most likely the speedometer.
no way a tire size difference is going to cause a speedometer that originally showed 0 mph when the car was stopped to start showing 5 mph when the car is stopped.
no way a tire size difference is going to cause a speedometer that originally showed 0 mph when the car was stopped to start showing 5 mph when the car is stopped.
Might be a semantics issue...he might mean 5 MPH WHEN moving as "all the time"...
Then again, my dad's '67 SS/RS was pegged so often, the speedometer read 10 MPH at a stop...but was reasonably accurate once he got moving.
We REALLY need to know the tire size, and quite frankly, I don't understand why he hasn't told us the one piece of information that would pretty much help us nail down what the problem is.
Might be a semantics issue...he might mean 5 MPH WHEN moving as "all the time"...
Then again, my dad's '67 SS/RS was pegged so often, the speedometer read 10 MPH at a stop...but was reasonably accurate once he got moving.
We REALLY need to know the tire size, and quite frankly, I don't understand why he hasn't told us the one piece of information that would pretty much help us nail down what the problem is.
245/55R16 sorry I took so long I've been busy with work
