Do I really need four?

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Denvermike

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One front tire on my wife's car is bad. Was told at a tire store that because her Subaru is an AWD that I need to buy four tires. The rears have well over half the tread left. I have no problem getting a pair for the front. What is the truth?
Thanks all,
Mike
 
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Sounds like someone is trying to sell you 3 tires you don't really need! 65'
 
How old are they? What is the DOT date code on each of them? Age of a tire has as much to do with a tires life span as tread depth does.
 
Here’s a link that may shed some light on the subject. Scroll down to #3 Vehicle Type. It talks about AWD vehicles and if you have to replace one tire, they shouldn’t vary more than 2/32” from another.

If it were me, I’d look for a good used tire with the same tread depth as the others. This works so long as you’re comfortable with an unknown tire. Les Schwab may be able to help you out.

Can I Replace Just One Tire on My Car? | Virginia Tire & Auto.
 
Generally yes you would want 4 of the exact same tire on an AWD car unless the system was an entirely open-diff system. but most Subaru's have a center diff with clutches in it and if one front tire is smaller you could have excess wear on those clutches
 
My son builds a lot of Subaru motors for a Subaru speed shop. A car was making noises from the trans or diff. I heard them talking that it was caused by the owner driving it on a low tire for a couple miles. I believe it is critical to have 4 of the same tires on these cars.
 
Yes, all wheel drive cars require all 4 tires be the same size and relative same diameter.
 
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I read all the responses, BUT, a good tire shop can match the diameter and tread of your existing tires. I have sold new and used cars, tires and accessories, and don't "buy" that line. What does your manual tell you? You could also call contact Subaru customer support. So... if you put your donut spare on your Subaru, it destroys the transaxles or what? Sorry for the rant, but.... my guess is that half their customers buy all four tires no questions asked, which means it works for the sales guy 50% of the time. I would just get some solid facts before I spent that kind of cash.
 
SpikeWills69 said:
I read all the responses, BUT, a good tire shop can match the diameter and tread of your existing tires. I have sold new and used cars, tires and accessories, and don't "buy" that line. What does your manual tell you? You could also call contact Subaru customer support. So... if you put your donut spare on your Subaru, it destroys the transaxles or what? Sorry for the rant, but.... my guess is that half their customers buy all four tires no questions asked, which means it works for the sales guy 50% of the time. I would just get some solid facts before I spent that kind of cash.
Click to expand...
Yes the doughnut is to get it off the road and to a service station only. They got the manual out and read it. Its in there It was a WRX
 
Oldmanmopar said:
Yes the doughnut is to get it off the road and to a service station only. They got the manual out and read it. Its in there It was a WRX
Click to expand...
Some AWD vehicles nowdays don't even have a spare.
 
Denvermike said:
One front tire on my wife's car is bad. Was told at a tire store that because her Subaru is an AWD that I need to buy four tires. The rears have well over half the tread left. I have no problem getting a pair for the front. What is the truth?
Thanks all,
Mike
Click to expand...
It's your wife, what's her life worth? My wife drives a 2016 AWD Ford Edge Sport. I keep the tire pressure where it is suppose to be and rotate her tires every 5000 miles. Her tires wear evenly. When they hit 5-6 years old I replace them.
 
Yes, it is critical. The manufacturers of AWD vehicles recommend that when you buy tires, buy them in sets of four and try to even get sequential serial numbers. At the very least, get them from the same batch. The reason is because AWD vehicles have what's called a viscous coupling instead of a transfer case. Even slight variations in tire diameter front to rear can burn the viscous coupling up. I've seen it first hand on an AWD Durango. This is why I always recommend people go 4X4 instead of AWD. Like Kitty's Escape. It's a 4X4 Escape, not an AWD Escape. They make both. Kitty's car has a bonifide transfer case, not a viscous coupling.
 
Yes replace all 4. Yes they can shave new tires down but buy new tires just to reduce them to 1/2 worn out. Some AWD have a fuse you can pull if you have to run the doughnut. Buy the extended warranty, It paid off when my wife's Journey took a nail in the side wall and her tires were like 15% worn.
 
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