Tag: speedometers

16 Posts

why does cold weather make the speedometer go haywire
Oct 25, 2012

Mary's Speedometer Hates the Cold

Dear Car Talk

Mary's speedometer goes nuts when it gets cold. Tom and Ray think she needs a new instrument cluster. Find out how Mary can save money on this fix, right here.


does the speedometer calculation assume a certain tire tread depth
Oct 01, 2010

How much does tread wear affect the speedometer reading?

Dear Car Talk

It occurred to me the other day that as a car is driven and the tires wear down, each tire's circumference decreases. Since the speedometer measures speed through the revolutions of the drive shaft or something, and then converts that...

tires speedometers

Are speedometers accurate
Oct 01, 2009

Are speedometers "false advertising?"

Dear Car Talk

My 9-year-old son asked me why the speedometer on cars indicate speeds much higher than legal driving speeds. If it is illegal to drive 100 mph (or faster), then why indicate that the car can travel that fast in the first...


May 01, 2008

A 7 year old asks, "Why do speedometers go up to 120 mph?"

Dear Car Talk

My name is Daniel. I drive a 2005 Escalade (OK, it's a toy car). I am 7 years old. Here is my question: Why do the speedometers in cars go up to 120 mph, when you are only allowed to go 65 mph...


Jul 01, 1999

What could be causing my speedometer to fail and the "check engine light" to come on?

Dear Car Talk

I have a Jeep Cherokee with four-wheel drive and the liter straight six I love it However occasionally the speedometer fails to register and the check engine light comes on This usually occurs on the first trip of the day...

sensors check engine light speedometers

May 01, 1999

Does tire size impact your speedometer readings?

Dear Car Talk

I'm having a dispute with my father-in-law who in a past life was a large- vehicle diesel mechanic Even though I'm a banker with no mechanical training whatsoever I still think he must be wrong He swears that the size...

tires wheels speedometers

Sep 01, 1996

How do speedometers work without a cable?

Dear Car Talk

I have just recently purchased a Dodge Caravan I was mystified when I heard that the speedometer doesn't have a cable anymore Could you explain how the speedometer works without a cable -- Steve RAY Will miracles never cease Next...


Dec 01, 1995

Do bigger wheels make the speedometer read faster or slower?

Dear Car Talk

Does putting bigger wheels on your car make the speedometer read faster or slower I've got a bet on this Jim RAY The speedometer will read slower Jim The speedometer reading is based on how many times the axle turns...

bets wheels speedometers

Mar 01, 1995

Could suspicious tachometer readings be caused by a change in wheel or tire size?

Dear Car Talk

I enjoy your column but I think you goofed recently You answered a letter from Ken who noticed that his tachometer was reading about rpm higher than it used to at miles an hour Based on his information you correctly...

tachometers speedometers wheels tires myths

Jan 01, 1994

The speedometer on my ' Toyota Camry is calibrated up...

Dear Car Talk

The speedometer on my ' Toyota Camry is calibrated up to mph Is this because a it is really capable of going mph b it provides for a nice symmetrical layout with mph being straight up at the top c...