# "New tires on the rear" law **URL:** \ **Category:** Factual Questions\ **Created:** [June 25, 2012, 1:08pm UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239 "2012-06-25T13:08:28Z")\ **Posts on this page:** 13\ **Page:** 3
**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\ **Post date:** [June 26, 2012, 9:46am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/41 "2012-06-26T09:46:34Z")
> [@Gary\_T](#): > > Well, now you know whom to do business with, and who’s a lying sack of shit. Agreed. While they’re not obliged to service anyone’s car, there’s no need to abuse your customer if you don’t agree with the service they want. ---
**Author:** ![ZenBeam](https://avatars.discourse-cdn.com/v4/letter/z/3ab097/32.png) [@ZenBeam](https://boards.straightdope.com/u/ZenBeam)\ **Post date:** [June 26, 2012, 4:22pm UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/42 "2012-06-26T16:22:28Z")
> [@Rick](#): > > Of course the shop can refuse to put them where the customer wants, just like I often **refuse to plug a tire** (not safe, no longer an industry accepted practice), or to repair a puncture that in my estimation would result in an unsafe repair. Plug a tire in or near the sidewall (which I’ve previously heard is unsafe), or plug a tire anywhere in the tread area? Is this relatively new? [/hijack] ---
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [June 26, 2012, 4:41pm UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/43 "2012-06-26T16:41:07Z")
> [@ZenBeam](#): > > Plug a tire in or near the sidewall (which I’ve previously heard is unsafe), or plug a tire anywhere in the tread area? Is this relatively new? [/hijack] Plugging it anywere. I first asked about this [eight years ago](http://boards.straightdope.com/sdmb/showthread.php?t=294191), but that was after several years of having the inside patches. So, it’s within the past 10-20 years in my area that all the garages have moved away from plugs. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [June 27, 2012, 1:59am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/44 "2012-06-27T01:59:27Z")
> [@ZenBeam](#): > > Plug a tire in or near the sidewall (which I’ve previously heard is unsafe), or plug a tire anywhere in the tread area? Is this relatively new? [/hijack] Anywhere. The problem with a plug is the guy doing the plug cannot see what damage has been done to the inside of the tire. The correct industry practice is to dismount the tire and inspect and if everything looks OK install a plug/patch from the inside. A plug/patch is a patch with a hard on. It has a plug attached. The patch seals the hole and the plug portion prevents water intrusion into the wound channel which might cause corrosion and a failure at a later date. This is the only way we will repair a tire at my store. ---
**Author:** ![Shosy](https://avatars.discourse-cdn.com/v4/letter/s/919ad9/32.png) [@Shosy](https://boards.straightdope.com/u/Shosy)\ **Post date:** [June 27, 2012, 6:12am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/45 "2012-06-27T06:12:08Z")
Well when I worked on cars, I always, and the customer normally requested, the new tires go on the front, rear or front wheel drive not withstanding. However, tire manufacturers do suggest the best tires go on the rear, and as someone pointed out, it’s nothing to do with blowouts, it has to do with braking. It’s the same reason why it’s suggested to put snow tires on all 4 wheels, ABS aside. It’s also the same reason why you should chain all 4 wheels as well. Now I know, understand, and believe the rational. Yet, on the other hand I know that under normal conditions, ie I’m not trying to floor the brakes going downhill on an icy mountain road, that it’s better that the best tires are on the front. I need 2…not 4 but TWO new tires, and I want them on the front. The worn tires are on the rear. I’d like them to put the new ones on the front, if they want to charge me a modest fee because they need to take off 10 additional lug nuts to do it, thats fine. If not I’ll just move them myself. ---
**Author:** ![The\_Universe\_Lashes\_Out](https://avatars.discourse-cdn.com/v4/letter/t/8797f3/32.png) [@The\_Universe\_Lashes\_Out](https://boards.straightdope.com/u/The_Universe_Lashes_Out)\ **Post date:** [June 27, 2012, 6:59am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/46 "2012-06-27T06:59:19Z")
> [@Rick](#): > > The problem is you cannot predict if the blowout will occur on a straight piece of road or a curve. I do know which way Mr. Murphy will vote. > Look all the people that are in the business (Tire Rack, Michelin etc) all say new on the rear. No one has provided a cite for new on the front. Despite this lack of cites to support their position of ignorance the NIF people stick their fingers in their ears and go La-La-La I can’t hear you, my post is my cite. Well, it sure seems like getting the new tires on the front would be the better option. But I don’t know shit about cars. The tire place I usually go to does it as standard practice. Maybe I should be going somewhere else? ---
**Author:** ![Cheesesteak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cheesesteak/32/3694_2.png) [@Cheesesteak](https://boards.straightdope.com/u/Cheesesteak)\ **Post date:** [June 27, 2012, 9:51am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/47 "2012-06-27T09:51:36Z")
> [@Shosy](#): > > Yet, on the other hand I know that under normal conditions, ie I’m not trying to floor the brakes going downhill on an icy mountain road, that it’s better that the best tires are on the front. Based on what? The people who make and sell tires test their tires constantly and they ALL recommend putting them on the rear. All for the same reason. If you lose traction, you’re most likely going to lose it on your worn tires, not the new tires. If you lose traction in the front, you’re more likely to keep control of the car than if you lose traction in the rear. Why? Because, if you lose traction in the front and slow down, you stay in line and stop. If you lose traction in the back and slow down, the back wants to swing around and become the front, now you’re going sideways, and you have no control over anything. Put new tires on the front, you’re going to feel better traction, so you drive more aggressively, and put yourself at risk of the bad rear tires letting loose. The same thing happens with SUVs in the snow, the owners feel their 4WD, think they have tons of traction, and don’t realize that 4WD doesn’t help them turn or stop as well as they think, so they wind up in a ditch. ---
**Author:** ![voltaire](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voltaire/32/313_2.png) [@voltaire](https://boards.straightdope.com/u/voltaire)\ **Post date:** [June 27, 2012, 11:05am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/48 "2012-06-27T11:05:25Z")
> [@Shosy](#): > > Now I know, understand, and believe the rational. > > Yet, on the other hand I know that under normal conditions, ie I’m not trying to floor the brakes going downhill on an icy mountain road, that it’s better that the best tires are on the front. Your example of what you consider abnormal conditions is a huge exaggeration. Conditions where it is safer to have the better tires on the rear don’t require ice, or downhill, or even hitting the brakes - much less all three simultaneously. It includes common situations where even a very careful driver may need to swerve quickly to avoid an accident or has to drive in the rain and take a curve on a mountain road or a highway off-ramp. Slight and predictable under-steer is always preferable to major and sudden over-steer, unless you’re a drifter or rally racer on a closed course. ---
**Author:** ![kayaker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kayaker/32/441_2.png) [@kayaker](https://boards.straightdope.com/u/kayaker)\ **Post date:** [June 27, 2012, 11:57am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/49 "2012-06-27T11:57:34Z")
> [@Una\_Persson](#): > > It sounds very similar to the apocryphal case of a confused average person standing in a shop while a bunch of smirking mechanics say “nope, sorry little lady, I know you just came in for brakes but the law says I can’t legally let you drive out of here on those tires. You have to buy 4 new ones from us before we’ll take your car off the rack…and you need some new muffler bearings too; don’t want to break any noise ordinances either! Heh heh…” When my car was having exhaust issues, I stopped for a “free exhaust inspection” at an exhaust shop beginning with the letter “M”. The mechanic had my car on the lift and suggested costly repairs, which I felt (and later proved) were overkill. He then refused to return the vehicle, saying it would be illegal to do so, citing safety concerns. I got out a pen and wrote down his name and other info. He explained, while I wrote, the payment options accepted. I then told him I had to go find a payphone (this was pre-cellphones) to file a police report. He returned my vehicle. ---
**Author:** ![Zep\_Tepi](https://avatars.discourse-cdn.com/v4/letter/z/59ef9b/32.png) [@Zep\_Tepi](https://boards.straightdope.com/u/Zep_Tepi)\ **Post date:** [June 27, 2012, 1:30pm UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/50 "2012-06-27T13:30:40Z")
[quote=“Shosy, post:45, topic:626239”] However, tire manufacturers do suggest the best tires go on the rear, and as someone pointed out, it’s nothing to do with blowouts, it has to do with braking. Shosy. The majority of braking is on the front of the car not the rear. I would imagine 65% front 35% rear. if you look, your discs are much smaller on the rear than on the front. ---
**Author:** ![Shosy](https://avatars.discourse-cdn.com/v4/letter/s/919ad9/32.png) [@Shosy](https://boards.straightdope.com/u/Shosy)\ **Post date:** [June 27, 2012, 1:45pm UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/51 "2012-06-27T13:45:46Z")
[quote=“Zep\_Tepi, post:50, topic:626239”] > [@Shosy](#): > > However, tire manufacturers do suggest the best tires go on the rear, and as someone pointed out, it’s nothing to do with blowouts, it has to do with braking. > Shosy. The majority of braking is on the front of the car not the rear. I would imagine 65% front 35% rear. if you look, your discs are much smaller on the rear than on the front. Obviously anyone who has done brakes know this simply from the wear, or especially if they’ve ever ridden a motorcycle. However that doesn’t change the fact that if you lose traction in the rear during braking two things happen. 1. The transfer to the front brakes is less effective (also, the brake modulator (unrelated to ABS but these days they are the same unit or integrated into the master cylinder, applies the rear brakes before the front brakes). 2. the rear end comes around, sometimes in an unpredictable fashion because even if the wheels aren’t locked up, and turning at the same rate as the front, they still carry load which may cause the vehicle to pivot off the front tires. Fear of this is one of the reasons that in the past before ABS became widespread, it was common for truckers to disconnect their front brakes. ---
**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\ **Post date:** [June 27, 2012, 1:46pm UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/52 "2012-06-27T13:46:39Z")
> [@Zep\_Tepi](#): > > The majority of braking is on the front of the car not the rear. I would imagine 65% front 35% rear. if you look, your discs are much smaller on the rear than on the front. What do you suppose would happen if that rear 35% suddenly went away, while leaving the front 65% functional? Unbalanced braking _is_ a real risk, in wet-road or slippery-road conditions, when the rear tires are too worn to deflect water effectively. But the key is the wear and the weather. Where I live I’m rarely driving in the rain, so I’m fine putting a pair of tires with 6/32" or more of tread on the rear axle. If you live in Arizona where it never rains, you don’t have to worry about this at all. ---
**Author:** ![thelabdude](https://avatars.discourse-cdn.com/v4/letter/t/dc4da7/32.png) [@thelabdude](https://boards.straightdope.com/u/thelabdude)\ **Post date:** [June 28, 2012, 1:41am UTC](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239/53 "2012-06-28T01:41:51Z")
I agree it is likely the same liability crock that forces me to to buy speed rated tires that are totallly wrong for my style of driving. I often show up with just the wheels. I take the3m home and mount them in the rear where **I think** they should be. [Previous page](https://boards.straightdope.com/t/new-tires-on-the-rear-law/626239.md?page=2)