# Do mechanics have a way to check tire wear other than looking at and feeling the tire? **URL:** \ **Category:** Factual Questions\ **Created:** [October 30, 2013, 8:24am UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632 "2013-10-30T08:24:05Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Quintas](https://avatars.discourse-cdn.com/v4/letter/q/48db29/32.png) [@Quintas](https://boards.straightdope.com/u/Quintas)\ **Post date:** [October 30, 2013, 8:24am UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/1 "2013-10-30T08:24:05Z")
Some sort of laser tool or infared or something?šŸ˜‰ Obviously I dont know what iā€™m talking about. On my new (to me) car it feels like there is a tiny up and down shake even on very smooth pavement. I didnā€™t even notice until someone pointed it out and now I cant tell if iā€™m just over analysing tiny bumps in the road or not. The tires are about halfway through their life. Theyā€™ve been rotated and the car got a 4 wheel alignment. But it feels like perhaps it got out of alignment previously and one tire may have overly worn enough to give it a tiny shake. Iā€™ve inspected the tires and felt along the inside and nothing stands out by feel. Visually they are fine. Is there something they can do to see a wobble or bump other than just visually and physically inspecting the tire for an obvious groove or bump? As I said, itā€™s so tiny you dont even notice until itā€™s pointed out. I doubt I would replace the tires yet but iā€™d love to know if the shake is real or if iā€™m just overly sensitive due to having a new car payment. ---
**Author:** ![engineer\_comp\_geek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/engineer_comp_geek/32/504_2.png) [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)\ **Post date:** [October 30, 2013, 8:56am UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/2 "2013-10-30T08:56:08Z")
They can put the tire on a machine and balance it. If you are curious, this video shows one of the machines: There are many other things besides a tire out of balance that can cause a shake. A ā€œbumpā€ on the tire can be caused by the steel belts inside breaking and shifting around. If that happens you need to replace the tire. A bent wheel can cause shaking. I would think that they would notice a bent wheel while doing the alignment, but who knows. Did anyone driving the car hit a curb since it was aligned? The tire might have just picked up dirt/mud or something and that could be causing it to go out of balance. A different type of problem like a worn CV joint or a bent axle or bad wheel bearings can all cause shaking. A broken motor mount can cause shaking. Some types of transmission problems (like a problem with the lockup mechanism on the torque converter) can cause shaking. Warped rotors can cause shaking. This will usually be much more noticeable while you are actually applying the brakes. A good mechanic should be able to sort it out for you. ---
**Author:** ![glaeken](https://avatars.discourse-cdn.com/v4/letter/g/e8c25b/32.png) [@glaeken](https://boards.straightdope.com/u/glaeken)\ **Post date:** [October 30, 2013, 9:43am UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/3 "2013-10-30T09:43:36Z")
I have seen a tire laser scanner that gave a complete report on tire wear and exact tread depth. It seemed a little excessive to me. You can see one demonstrated on the below. [![](https://img.youtube.com/vi/ABwq5f3HkNc/maxresdefault.jpg "scanCONTROL - tire surface inspection using laser scanner") ](https://www.youtube.com/watch?v=ABwq5f3HkNc) I guess if you want as accurate a measure as possible of the health of your tire this is it. I donā€™t think most commercial tire places have these scanners as it seems more than is required for general motoring. ---
**Author:** ![tellyworth](https://avatars.discourse-cdn.com/v4/letter/t/977dab/32.png) [@tellyworth](https://boards.straightdope.com/u/tellyworth)\ **Post date:** [October 30, 2013, 10:34am UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/4 "2013-10-30T10:34:06Z")
I had a similar problem. A local tyre guy spent a few minutes with it on his balancing machine, and said there was a manufacturing problem with it that meant it couldnā€™t be balanced properly. The manufacturer replaced it under warranty (it was only about a year old). I imagine any decent tyre shop would either find the problem quickly or rule it out. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [October 30, 2013, 11:39am UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/5 "2013-10-30T11:39:00Z")
> [@](#): > > The tires are about halfway through their life. Theyā€™ve been rotated and the car got a 4 wheel alignment. But it feels like perhaps it got out of alignment previously and one tire may have overly worn enough to give it a tiny shake. Iā€™ve inspected the tires and felt along the inside and nothing stands out by feel. Visually they are fine. Generally the symptoms of a poor alignment donā€™t include a poor ride. Even if the alignment has caused premature tire wear it does not degrade the ride. Tire balance (among a bunch of other things) will cause a shake. Have all four tires balanced is an excellent starting place. When the tire is one the machine the technician will be able to visually tell if the rim is bent or the tire has a shifted belt or whatever. ---
**Author:** ![HoneyBadgerDC](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/honeybadgerdc/32/1033_2.png) [@HoneyBadgerDC](https://boards.straightdope.com/u/HoneyBadgerDC)\ **Post date:** [October 30, 2013, 12:30pm UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/6 "2013-10-30T12:30:21Z")
On the big trucks we do whats known as checking runout with a dial indeicator and tire mounted on truck. I have never seen that performed on a car but for a home test it could show a problem with the tire. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [October 30, 2013, 1:04pm UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/7 "2013-10-30T13:04:55Z")
> [@HoneyBadgerDC](#): > > On the big trucks we do whats known as checking runout with a dial indeicator and tire mounted on truck. I have never seen that performed on a car but for a home test it could show a problem with the tire. Iā€™ve used dial indicators on car tires but generally spinning it and using a good old Mk1 eyeball is adequate for cars. ---
**Author:** ![aceplace57](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/aceplace57/32/3500_2.png) [@aceplace57](https://boards.straightdope.com/u/aceplace57)\ **Post date:** [October 30, 2013, 1:41pm UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/8 "2013-10-30T13:41:56Z")
Coins are accurate gauges for tire wear. I learned this from my dad. Goodyear still recommends them. I check mine with a quarter every few months. > **[Goodyear Auto Service | Oil Changes, Brakes, & Engine Repair](http://www.goodyearautoservice.com/content/content.jsp?pageName=TreadDepth)** > > Trust Goodyear Auto Service for car maintenance services near you. Convenient locations for oil changes, brakes, tire rotations, engine repair & more. > [@](#): > > There are several popular ways to check your tire tread depth. One easy way is the penny test. Simply insert a penny into your tireā€™s tread groove with Lincolnā€™s head upside down and facing you. If you can see all of Lincolnā€™s head, your tread depth is less than 2/32 inch and itā€™s time to replace your tires. > > Another easy coin test is the quarter test. Insert a quarter into your tread groove. If the tread touches Washingtonā€™s head, you have at least 4/32 inch of tread remaining. ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [October 30, 2013, 1:59pm UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/9 "2013-10-30T13:59:52Z")
> [@aceplace57](#): > > Coins are accurate gauges for tire wear. I learned this from my dad. Goodyear still recommends them. I check mine with a quarter every few months. > > [http://www.goodyearautoservice.com/content/content.jsp?pageName=TreadDepth](http://www.goodyearautoservice.com/content/content.jsp?pageName=TreadDepth) 1. True, for general home maintenance checking. Of course, unless youā€™re jacking the car and turning the wheel to check at multiple points, you could miss a spot wearing prematurly because of alignment or suspension problems.\* 2. This is a board hosted on [what is alleged to be a computer](http://boards.straightdope.com/sdmb/showthread.php?t=706063) in the Good Olā€™ United States of America (USA! USA!). But some of our Canadian friends wouldnā€™t be able to use a quarter, since theirs is pretty unlikely to have an image of that traitor to His Majesty (at the time). Maybe they can fish a US quarter out of the bin of junk American coinage that seems to invariably creep across the border. \*Well, if youā€™re conscientious, you could do the quarter check all around the exposed (non-ground-contact) diameter of all the tires without jacking, but it would require some mild contortions to get to the parts of the tread near the ground and still get multiple accurate readings across the tread width. ---
**Author:** ![ducati](https://avatars.discourse-cdn.com/v4/letter/d/cc9497/32.png) [@ducati](https://boards.straightdope.com/u/ducati)\ **Post date:** [October 30, 2013, 2:58pm UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/10 "2013-10-30T14:58:20Z")
Experience tells a mechanic/tire guy how the tire is wearing and why. Having all four wheels balanced is where you start. An alignment will reduce wear, but not bounce. You may also have worn bushings allowing some vertical play, depending on the vehicle. And, if you just want a quick measurement of tread depth, why thereā€™s a tool for everything. [Analog](http://www.promo-wholesale.com/Upfiles/Prod_q/Pen-type-Tire-Tread-Depth-Gauge_20090712619.jpg), like mine, and [digital](http://image.made-in-china.com/2f0j00ICJEDweKMPob/Digital-Tread-Depth-Gauge-310-930.jpg)if youā€™re super lazy/anal. The Mk1 eyeball is an incredibly precise and calibrated tool that can detect many problems. If yours isnā€™t properly calibrated, itā€™s important to find a mechanic with one that is! ---
**Author:** ![J-P\_L](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/j-p_l/32/3156_2.png) [@J-P\_L](https://boards.straightdope.com/u/J-P_L)\ **Post date:** [October 30, 2013, 8:17pm UTC](https://boards.straightdope.com/t/do-mechanics-have-a-way-to-check-tire-wear-other-than-looking-at-and-feeling-the-tire/672632/11 "2013-10-30T20:17:55Z")
[Tire tread depth gauge](http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=148) exist to find out how much a tire is worn, but it would not be the best way of finding an out of balance condition on a tire.