What is the "speedometer check" on the interstate?

I've seen these signs forever, but cannot for the life of me figure out what they are for and how to "use" them. I'm in the state of Oregon in case that makes a difference. I'm not sure that all states have these same signs?

Relevance

Those are measured miles for the purpose of checking the readings on your car. To use one, check the speed limit and do the math. 60 mph = 1 mile per minute. 55 mph = 1 mile in minute and 5 seconds. 50 mph = 1 mile in minute and 10 seconds. 65 mph= 55 seconds, 70 mph = 50 seconds.

Maintaining a constant speed, read the last digit of the odometer and check your second hand as you pass a sign. When passing the next sign, the last digit should be the same, and you time as noted above. Congratulations, your speedometer is correct, or maybe those ultra-low profile tires threw it off.

• Mayra
Lv 4
4 years ago

Interstate Love Song

• 3 years ago

What Is Speedometer

It's a measured mile or perhaps more than a mile. Your odometer should show exactly one mile if it's accurate, and if you are showing 60 MPH on the speedometer, it will take exactly 60 seconds.

If it takes more or less, your odometer speedometer is fast or slow.

there is probably a white line on the highway or along the

side, also could be a post painted white or floresent.

this would be the start. then at (usually) a mile there is

another either painted line or post... marking one mile

to check your odometer and speedometer..