HarmsWay

While out on the town this past weekend I returned to my Q5 to find a rear tire completely flat. I'd run over a screw at some point. Anyway, pouring rain and all, I decided it was time to check out the 'spare' tire which I'd completely ignored for the first few years of ownership.

First look at the collapsable spare and I wondered how that could possible form into a tire capable of holding the weight of a Q5. I then tried to figure out why the tire had an electrical connector. It was attached to the plastic cover that appeared to be some kind of used oil collector. I thought maybe the tools were hidden in that cover but as I dug around I discovered it was the subwoofer so I put it aside out of the rain. Finally found the necessary lug wrench, jack and wheel pin. The tire took about 18 minutes to pump up to 50 psi (with a rest at 12 minutes to cool the tiny compressor). It got me home and the tire was repaired the next day.

So it does work but I would suggest people get familiar with the available equipment before they actually need it in an emergency. The biggest effort is still to come though - trying to fit all the bits and pieces back into their proper storage compartments, including the spare itself which apparently may not always collapse enough after use.

Do the US cars may have run flat tires and sealant?

SteveDu

And the car didn't have the Tire Pressure Monitor? I know it's standard in most cars in N. America.

joey jojo

nope, we have a collapsible spare with the electric pump as well.

and just to add to your post, pump up the spare BEFORE you mount it. i thought it'd be clever for me to put the spare on and then pump, but that doesn't work because of the way the spare inflates (to one side first, and then to the other side).

also, the US cars do have tpms that's based off the ABS system, if i'm not mistaken. in other words, there's nothing installed in the tire for the reading. the reading is simply based on the rotation speeds of the tires.

Redd

AFAIK a traditional TPMS system, US or overseas, will be a pressure sensor in the wheel. Which requires the tire to be unmounted about every 5 years for a battery change, and also prevents the use of tire sealant.

And costs money. And can cause air leaks because the tire sensor is o-ring mounted on the stem, and the O-rings can easily leak. In which case, again, you need to have the tires remounted to fix it.

So the newer and smarter solution, with ABS and traction control systems becoming so widespread, is to be clever and use the ABS wheel-rotation-counting software to determine if one tire is rotating at a different speed, indicating it has a different diameter, caused by a pressure difference. Really clever.

Also way cheaper to implement, so any company still using wheel mounted sensors is wasting a lot of money. And since there's no sensor, you can use tire sealant without worrying again. (Yeah!)

Games with run-flats, or no spares, or donuts or inflateables...you can justify anything but if you're out in the boonies, out of cell phone and tow call range, more than 50 miles from the next tire dealer, don't want to wait overnight or two nights for new tires to get shipped in from the nearest big city...a full size spare still makes sense for some drivers. Fifteen minutes to change to the spare versus an hour or two for a truck? Or a night or two?

I decided that since Audi thinks a can of sealant is good enough for the A8, an extra can of Slime and an injector pump (big can of slime, and the air pump will inject it into the tire and fill the tire completely, which a 'can' won't do) are my first line of defense. Unless I blow a sidewall, that should get me going again in less than 15 minutes, without needing to unload the rear compartment, or jack the car, or call for help.

The bit in the manual about "carry the spare tire around with you for a couple of hours, hold it dear till it deflates enough to fit it back in the well" pretty much nailed that coffin for me. Really? A couple of HOURS to change the spare back?

B490MTL

FYI when inflating the spare remove the tire valve, use the cap the other way around it has two prongs. You will be able to inflate your tire in less then 5 minutes. Just remember to screw the valve back.

Q5 Bob

As suspected, this spare tire set up sounds like a real PITA. If at all possible I would just wait for roadside assistance. I had a full size spare on matching wheels in my last two cars. Never had to use either, but it was nice to know they were there.

JGA5Cab

I blew out a tire and didn't know about the valve on the hose that needed to be closed. the pump was running and nothing was happening. I let this go on for way too long. I ended damaging the paint on the rocker panel because the jack is so poorly designed and has to be placed precisely. I got everything done up to removing the tire from the hub. The rim was fused to the hub because of salt. I couldn't get it off. I called Audi Roadside finally. It also didn't occur to me that there was an outlet in the cargo area. I ran the wire up into the car to the console area.

If you live in a salty area, go to Harbor Freight or somewhere with cheap tools and get a rubberized mallet. You may need to smack the wheel a bit to get it off.

That experience was truly a huge P.I.T.A. BTW, Audi sent some guy in a beat up old mini van who would have had no clue how to inflate the tire or where it was even located. READ UP

Redd

"remove the tire valve,"
FWIW, I wouldn't suggest that. If you remove the valve core, there's a good risk of losing it. And if not losing it, dropping it or getting dirt, pocket lint, whatever on it, and then the o-ring won't seat properly. Or, it may simply tear from being unseated and reseated.
Simpler to just KISS, inflate the tire with the valve core in place, the way it is designed to be inflated. If the tiny factory pump is inadequate for that...there are plenty of bigger faster stronger pumps on sale all the time.
And if you live someplace where there is winter...do you really want to screw around with valve cores at night on the side of the road in slush and snow? Nah. KISS.

One day I'm going to pull out the trim and see whether a full wheel can be coaxed in there.

Bob Petruska

there is plenty of room to have one. Cost isn't a factor as the collapsable spare and compressor cost X times more. Weight also isn't a factor. I just don't understand this with Audi at all.

Do you know that 30% of GM cars come without a spare.

When you have no spare, badly cut tire that can't be fixed and not near a large city, you call a tow truck, he tows you to a tire dealer if he is open (if not you stay overnight somewhere), next day you go to the local tire store, now you just bought a set of premium brand tires a month ago and they don't carry them so they sell you something you don't want for $200 and you will need to change it to the premium brand tire fairly quick for another $200-300. Just because you have no spare???

Redd

Bob, I'm not sure there is room. Someone said they took out the "liner" and the body pan intrudes too far to allow a full sized spare, which is why I want to get my own eyes in there.

Putting a spare in a car can add 40# to the gross vehicle weight, which impacts the EPA fleet rating for mpg, and adds costs to many things including the suspension, which is built to carry that weight. So I can understand the cheap SOBs omitting something the mass market has no use for.

I mean, most folks can't or won't change their own flat. Although I have a friend who got her license in France many years ago, who said "Do you know they make you show that you know how to change the spare, or you can't get a license?!"

When it is engineers versus cost accountants, you know who will win every time, unless the marketing boys can prove them wrong.