Why get AWD?

Everytime I blow one tire and have to buy 4? [emoji16]

You could buy one new one and have it shaved down to match tread depth of the others. With AWD, tread depth should usually have no more than 1/4 inch variance between all tires.
 
Disagree. That's not been my experience.

Seconded.

But Over time, the front camber on my 528i moved to 0.0 degrees which worked fine just not so great for cornering. Modern cars hold their alignment quite well.

Maintaining your car is always changing the oil on time and other items like your air filter, spark plugs etc
 
You could buy one new one and have it shaved down to match tread depth of the others. With AWD, tread depth should usually have no more than 1/4 inch variance between all tires.

1/4" is more than 6mm which is more than half of the useable tread in most new tires.
 
1/4 inch VARIANCE, NOT 1/4 inch of tread left...

Understood. 1/4" is 8/32" If you buy a new tire with 10/32" of tread, the only way it could vary from the other tires by 1/4" is if the other tires were 2/32" remaining tread or less. At 2/32" they are ready to be replaced anyway.

You'd be an original kind of crazy if you bought one new tire and shaved it down to 2/32" so you had a matching set of tires that all needed to be replaced.
 
Ideally it would be good to change tires in pairs. However if you should decide to change just one tire for budget purposes, you should also consider the thread depth of the opposite tire. If it's nearing it's life then I guess it really needs replacement.
 
Understood. 1/4" is 8/32" If you buy a new tire with 10/32" of tread, the only way it could vary from the other tires by 1/4" is if the other tires were 2/32" remaining tread or less. At 2/32" they are ready to be replaced anyway.

You'd be an original kind of crazy if you bought one new tire and shaved it down to 2/32" so you had a matching set of tires that all needed to be replaced.
You're missing the point. It doesn't literally have to be a 1/4 inch. Maybe a 1/4 inch is just a bad example. It varies. Some manufacturers offer a variance as little as 2/32 inch. Are you going to throw away 3 good tires then if all the tires are fairly new? My point is this, AWD demands 4 tires with a circumference fairly close to one another set by the manufacturer otherwise you're going to damage the AWD system. FWD isn't so picky but if I had to replace a tire I would do it in pairs per axle putting the good tires on the rear.
 
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I wanted to do some math on the actual cost of the extra FUEL USAGE for the AWD.

Driving 12,000 miles per year, and our AWD getting a combined avg of 25mpg for the year equals 480 gallons of fuel a year. (12000/25=480)

If we had a FWD our combined mpg for 12,000 miles would be 27 mpg, or 445 gallons used per year. (12000/27=444.44)

So if AWD makes us use 35 more gallons of fuel over a year of driving 12,000 miles, at an avg cost of $2.50 a gallon, that means our annual fuel bill is $87.50 a year higher.
 
the good tires on the rear.

I don't understand why people do this for FWD cars. The wheels that drive, stop and steer need to have less traction just so the rear end doesn't step out on you?

If you're such an inexperienced driver (not you, but everyone else who thinks this is the rule) that you're worried about some oversteer, you're not gonna be causing a FWD car to drift because you just don't have the skill to do that. It makes absolutely zero sense to me.
 
I don't understand why people do this for FWD cars. The wheels that drive, stop and steer need to have less traction just so the rear end doesn't step out on you?

If you're such an inexperienced driver (not you, but everyone else who thinks this is the rule) that you're worried about some oversteer, you're not gonna be causing a FWD car to drift because you just don't have the skill to do that. It makes absolutely zero sense to me.

Agree, always put the best tires on the front on FWD.
 
I wanted to do some math on the actual cost of the extra FUEL USAGE for the AWD.

Driving 12,000 miles per year, and our AWD getting a combined avg of 25mpg for the year equals 480 gallons of fuel a year. (12000/25=480)

If we had a FWD our combined mpg for 12,000 miles would be 27 mpg, or 445 gallons used per year. (12000/27=444.44)

So if AWD makes us use 35 more gallons of fuel over a year of driving 12,000 miles, at an avg cost of $2.50 a gallon, that means our annual fuel bill is $87.50 a year higher.

If you really need it, I would think it would be worth it no matter the cost.

But I drive about 30-35K per year and live in Texas. I usually trade around 100K, so with your formula it would cost me an additional $750 at the low prices we have for fuel now. Add $1300 for additional purchase price. And then there is the tires. If I run over something and need to replace 1 tire, I will replace 1 tire. I might replace 2 if they are worn pretty bad and put them on the front. No way I am replacing 4 tires if they don't all need it. Also, I am out in the middle of nowhere a lot. Not sure what you AWD guys do when you have a blowout. I guess you drive on the temporary spare that has a significant difference in outside diameter? What if you are 100 miles from a tire shop?
Anyway, at least $2k saved and probably much more for a feature I don't need and will possibly be a hindrance to me. That will get me the HUD, power passenger seat, and memory driver's seat and some money left over.(cheers)
 
If you really need it, I would think it would be worth it no matter the cost.

But I drive about 30-35K per year and live in Texas. I usually trade around 100K, so with your formula it would cost me an additional $750 at the low prices we have for fuel now. Add $1300 for additional purchase price. And then there is the tires. If I run over something and need to replace 1 tire, I will replace 1 tire. I might replace 2 if they are worn pretty bad and put them on the front. No way I am replacing 4 tires if they don't all need it. Also, I am out in the middle of nowhere a lot. Not sure what you AWD guys do when you have a blowout. I guess you drive on the temporary spare that has a significant difference in outside diameter? What if you are 100 miles from a tire shop?
Anyway, at least $2k saved and probably much more for a feature I don't need and will possibly be a hindrance to me. That will get me the HUD, power passenger seat, and memory driver's seat and some money left over.(cheers)

Yikes that is a lot of miles! At your pace you would also have to add ++ the extra $ maintenance for the rear diff.

Since we lease, we don't have to worry about the rear diff service or the tires as the originals are still on the car when we turn back in.
 
Yikes that is a lot of miles! At your pace you would also have to add ++ the extra $ maintenance for the rear diff.

Since we lease, we don't have to worry about the rear diff service or the tires as the originals are still on the car when we turn back in.

I know, lots of miles lol. By the way, I just checked and the temp spare is about 2.5" less diameter than the factory tires.

Since guys are talking about mm of tread depth and shaving tires, what do AWD people do when you have a flat in the middle of nowhere? Call a tow truck? Just curious.
 
You ride on your spare. It's not like you can't drive on a different size tire to safely get home...
 
I know, lots of miles lol. By the way, I just checked and the temp spare is about 2.5" less diameter than the factory tires.

Since guys are talking about mm of tread depth and shaving tires, what do AWD people do when you have a flat in the middle of nowhere? Call a tow truck? Just curious.
Our owner's manual doesn't give any warning specifically for AWD when we put on the temp spare. Othe AWD I've owned either give you a full-sized spare or says a tow truck is needed with all 4 wheels off the ground while towing when you have a flat tire.

▼ Spare Tire
Your Mazda has a temporary spare tire. The temporary spare tire is lighter and smaller than a conventional tire, and is designed only for emergency use and should be used only for VERY short periods. Temporary spare tires should NEVER be used for long drives or extended periods.
 
Good info Yrwei. I always move the temp spare to the rear when I am a long way from getting it repaired/replaced, so no drivetrain involved. Another reason FWD is better for me.

I kinda laughed when 7 said you drive home. Sometimes I'm 450 miles from home and and still in Texas, lol.

And I think run-flats are now common for a lot of AWD vehicles and they have no spare, or they have a full size spare like you mentioned.
 
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