KLF

I refuse to buy any vehicle that has a temp spare. Ever. Not gonna happen. Total deal breaker.

When I bought my daughter's Corolla, I refused to take delivery until they put a full sized spare in the well in the trunk.

Run-flats are simply insane.

bitkahuna

iTrader: (20)

you can blame the federal govt's gun-to-the-head policy for fuel economy. cars will continue to get less content and eventually have seats made of rice paper and airbags made of recycled butterfly wings to save weight. in fact why not make the whole exterior of paper with just a reinforced 'box' around the occupants to meet safety requirements (another govt gun-to-the-head which has increased costs).

as an aside, if a car could be offered without air bags, tpms (now required), stability control, and cost $5k less than competitors with those things, i wonder if it would sell... but we'll never know. oh wait, we had tons of cheap cars like that on the road but the govt's 'cash for clunkers' mandated they be destroyed.

i personally don't see what's so bad about the donut spare - you use it get to a place to get the flat tire fixed/replaced, and move on, what's the big deal?

mmarshall

Some automakers use the excuse that their "research" shows that very few owners actually change their flat tires anymore.....they either call AAA or the company's Roadside-Assistance-plan (which, more often than not, is actually a AAA-contract). So, in their view (not mine), that lessens the need for a traditional spare tire. However, the fact that traditional spares are still used in off-road trucks/SUVs shows that they are still, in fact, needed, and, in all types of vehicles (off and on-road alike) the fifth real tire/wheel is still useful for tire rotation and extending the life of the other four.


On a full-time AWD vehicle, donuts can place a lot of stress and heat build-up on both the center and front or rear differential, depending on which end of the vehicle the donut is used. It does that by constantly having a big difference in rotation speed between the front/rear and side-to-side wheel-rotation speeds. Center differentials are designed to correct for only momentary differences in front/rear tire-rotation speeds as all four tires gain traction, not continual and/or significant differences. That is why, on Subarus and similiar full-time AWD vehicles, a fuse-puller is sometimes provided to deactivate the AWD and run only two drive wheels when a donut/temporary sparte is used. If the flat is on one of the two remaining drive wheels (usually the front), it must be exchanged with a good tire on the back, and the donut shifted to the deactivated end of the car, before you can proceed to the tire shop.

With full-size traditional spares, this is usually not a problem on AWD vehicles, unless the other tires are badly worn, which would give one tire (the spare) with a slightly lower rotation-speed and the other tires with faster rotation. That is why, whan it is time for new tires on an AWD vehicle, it is best to replace them all at once so that they are all the exact same outside diameter, and not mixed.

KLF

Well, let me start with how unsafe they are. There is no way that tiny little tire has the same traction, cornering, and braking ability that a full size tire has. They are typically rated for 50 miles at 50 mph max. I am sure you have seen cars on the road with these tires installed, traveling much faster than that. Too many people put them on and think they can keep on truckin' at the same speed, and they drive around on them for days, going way over the mileage rating. Very very unsafe situation, ESPECIALLY in poor weather.

#2: Once they are used, they are junk. There is no way to replace just the tire. No shop that I am aware of will replace the tire, you have to toss the whole thing and get a new one. And landfills, especially in New England, don't accept them. The last time I had one in a car, I went out and bought a full sized rim & tire so I could get rid of it. The donut was brand new, unused, still had the wiskers on it. I tried many places to GIVE IT AWAY and nobody would take it. And our solid waste facility would not accept it like it was, they wanted it unmounted so the rim could go to the scrap metal pile, and the tire could go to the tire recycling pile. But, I could not find a shop that would dismount it for me. How stupid is this: I had to take my sawzall and CUT the unused tire off the rim.

#3: TODAY was a perfect example of the biggest reason why I hate them and will never have one again. We were on our way home from church, and I passed a Honda Accord on the opposite side of the road, with a flat, flashers on. So, I spun around to see if I could offer to change it for them. The nice older gentlemen behind the wheel explained that he had to wait for a repair truck to patch the tire anyway, but I could tell from the gash in the side of the tire that it was gonna have to be replaced. He and his wife were at the beginning of a long drive, they had many miles to go, and there's no way they would make it on the donut. They had to get it fixed NOW.

Similar story: many years ago (mid-80s) my wife was driving our almost-new Mazda 626 from NH all the way to Ohio. She had our infant son in the car with her. They had just gotten into PA, it was very late at night, and she got a flat. Because of the donut spare, she had to drive to the closest tire shop out in the boonies, and sit in the parking lot ALL NIGHT (it was January) and wait for the place to open, so she could pay for a brand new tire to be installed. There's no way she would have made the rest of the trip on that donut.

Tires have definitely gotten more reliable, but they are not infallible. The last time I got a flat was on a snowtire in my ES, 3 years ago. I hit a HUGE pothole that was hidden in a puddle on a dark rainy night, it gashed both sidewalls in the tire, it went flat almost immediately. A run-flat would not have survived that incident, and then what would I do? I can only imagine the bill for that tow. I was able to swap the full-size spare on, and replace the tire at my leisure.

mitsuguy

iTrader: (2)

Not true at all.

At minimum, Firestone will replace them (they need to be ordered, but they will replace them).

Also, 50 miles at 50 mph is because of heat buildup. Its not trash when it hits 50 miles, its just like any normal tire in that regard - if there is tread (minimal, I know), then it is fine. On a hot road though, there is simply not enough surface area to dissipate the heat when driven for about 50 miles. If its not hot out or you keep the speeds lower, you are fine driving well more than 50 miles at a time.

The biggest problem I see with these, and even their full size brethren, is that people rarely check the pressure. Compact spare are almost all 60 psi.

KLF

Well, admittedly I am working on info that is probably out of date. My last experience with one of those stupid tires was about 10 years ago. I'm hoping the industry has at least figured out a way to replace the tire when it wears out.

I'll still never own one. I was very dismayed to find out that some of the Lexus models now come with them (GS, for instance, maybe others). When I was car shopping back in '03, I came very close to buying a Saab turbo, until I found out they also have them in all their models, and the well in the trunk won't accept a full-size tire. Pretty pathetic given how they are soooo concerned with safety in all their promotionals. I really wanted to by my daughter a Matrix last year, but it has the same issue.

bagwell

back on topic ---

from the SLIME website...http://www.slime.com/faq.html

My vehicle has a TPMS device; can I use SLIME?

TPMS STATEMENT OF COMPATIBILITY

As leaders in the tire care and repair industry, Accessories Marketing, Incorporated (AMI), the manufacturers of SLiME Tire Sealant wish to address the mandate set forth in the Transportation Recall Enhancement, Accountability and Documentation (TREAD) Act, passed in the fall of 2000. In response to this mandate, the National Highway Traffic Safety Administration (NHTSA) established the Federal Motor Vehicle Safety Standard that requires the installation of Tire Pressure Monitoring Systems (TPMS) to all vehicles by September 1, 2007.

From our findings, and after significant dialog with the leading manufacturers of TPMS devices, SLiME Tire Sealant will not damage TPMS devices. We understand TPMS manufacturers have conducted extensive testing to ensure their sensors remain operational after exposure to any chemical fluids that might come into contact with the sensors. This includes after market products, such as SLiME Tire Sealant. AMI has also conducted independent testing, which supports and verifies SLiME Tire Sealant’s compatibility with TPMS devices.

Currently, there are two types of TPMS devices available: Direct and Indirect. SLiME Tire Sealant’s TPMS formulation is compatible with all TPMS systems. However, it is important to note that once installed, Slime Tire Sealant may come in contact with the sensor in a way that renders the sensor TEMPORARILY inoperable until it is properly cleaned, inspected and re-installed by a tire care professional.

Because SLiME is a water soluble flat repair treatment, it is easily removed from the tire with water. At the time the affected tire is inspected by a tire care professional, they should clean the sealant from the tire, prepare the area and repair with a Rubber Manufacturer’s Association (RMA) approved patch/plug. The TPMS device should also be cleaned off with water to remove any sealant which may have come into contact with the device. Do not use any fine objects to ream and clean the small pressure sensor opening as it may damage the electronics. After the repaired tire is replaced and inflated the TPMS system will resume operating as normal.

Please note that SLiME is recommended as a REPAIR for all Over the Road (OTR) applications.

Byprodrive

iTrader: (1)

Anybody notice alot of the cars & trucks from the 1920's & 1930's had 2 spare tires? What happened to that? Better roads, better tires. Think people were having simular conversations then? "Wow do we dare venture out on the open road with only 1 spare tire?" Does it make sense to transport a spare tire that weighs 2 or 3 times what a "Space saver tire weighs & costs? By this logic I would expect that we should never leave home without a backpack filled with emergency supplies: (first aid kit, drinking water, defibulator, spare shoestring etc.) Anytime a driver exceeds the limits of his or his cars abilitys bad things can happen. If you are driving on a tire with a slow leak you have to adjust accordingly. If you are driving with a spacesaver tire adjust driving to prevent exceeding the limits of the tire. 25 years ago driving my mother in her car had a flat, installed spacesaver tire drove to our destination 70mph, 350 miles away, bought a replacement fullsize tire when it was convienant. Like all tires proper air pressure is the key, Spacesavers are usuall 60 psi.

KLF

* I disagree that a full size spare is "2 or 3 times" heavier. But, fortunately I don't own one to compare.

* Most cars have a well in the trunk that will fit a full-sized tire, so where is the space savings?

* All of my vehicles are equipped with emergency supplies: tools, tire plug kit, air compressor, jumper cables, fluids, first aid kit, even a blanket. My 24 year old pickup truck is equipped with a winch on the front bumper, locking differentials in both axles, and enough tools and spare parts to fix just about anything. I'd carry water if I could figure out a way to keep it from spoiling and freezing. I'm not a back woods survivalist militia type, but I like to be "that guy" that is prepared for almost anything, as it has come in very handy on lots of occasions.



We all accept a certain level of risk in our lives. To me, it is unacceptable to rely on that dangerous tire as a potential solution for myself and my family.