Last post on Feb 23, 2012 at 4:42 PM
You are in the Subaru Legacy & Outback
What is this discussion about?
Subaru Legacy, Subaru Outback, Tires, Wheels, Wagon
#107 of 124 Is replacing all four tires necessary?
Nov 07, 2010 (4:20 pm)
Last year, I purchased a 2005 Subaru Legacy with fewer than 30k miles on it. Anyhow, I recently realized that my back two tires are worn to the point of needing to be replaced; the two in the front are fine.
After going to several tire dealers, I was told by each of them that I would need to replace all 4 tires because all tires on an AWD must be the same make and have the same tread left on them. Moreover, my specific model of Tigerpaw is no longer made.
To compile the issue, when I bought the car (from a Subaru dealer) last year, the tires that were on it were different makes in the front and back (Tigerpaws up front / Goodyears in the back). At the time, I didn't know about this issue with AWD vehicles. I typically get all of my service done at this dealer. Should I bring this up to them? They are trying to sell me two new rear tires of yet another make.
Do I have a legitimate concern here? Do I need to replace all four, or should two new ones suffice? Should I bring this up to the dealer and complain?
Thanks for your help.
#108 of 124 Re: Is replacing all four tires necessary? [wired1]
Nov 07, 2010 (8:20 pm)
In a word .... YES. I've owned Subarus since 1991, and have always been told this. The only "exception" has been when one goes early on and the others have almost no wear at all. Even then it's been stressed to get the same mfr and tread pattern in the new one. Replacing both front or back only (as in 2 at a time) just doesn't work. Subarus can be very twitchy with bad tires or different wear patterns. Good luck!
#109 of 124 Re: Is replacing all four tires necessary? [wired1]
Nov 08, 2010 (10:40 am)
You're probably not going to notice any problems with the 2+2 configuration, but it does put additional stress on the car's center differential. That's an expensive repair, so I wouldn't chance it. In fact, I would definitely bring it up to the dealership that sold you the car, and have it documented, in the even you have a center differential failure in the not-so-distant future.
In the grand scheme of things, tires are cheap; I would just replace all four now and start fresh.
#110 of 124 Re: Is replacing all four tires necessary? [xwesx]
Nov 08, 2010 (3:37 pm)
With two different brands of tires on front and rear, I would be very leery of having a different rolling circumference, even with tires that were nominally the same size.
With the same model of tire on front and back, I have heard guidance that the difference in tread depth between front and back tires should be kept to 1/16" or less (so that the diameter difference is 1/8", or about 3mm, or less).
(Circumference is easier to measure on a tire, and the circumference difference will be 3.14 (pi) times the diameter difference, leading to a maximum allowable circumference difference of around 3/8", or 9-10mm. Not much, in other words...)
I don't think this is an absolute limit, but in sustained highway driving even a modest difference in diameter (really rolling circumference) is potentially leading to heating-up of the center diff, depending on the type of center-diff used.
#111 of 124 Help requested: Minus sizing for winter tires
Nov 23, 2010 (3:44 pm)
I've got a 2006 outback with 225/55R17 tires. We're going to get some winter tires (probably the Continental ExtremeWinter Contact - but I'd like thoughts on that as well). The Tire Rack website is recommending using a 225/60R16. What are thoughts on minus sizing in general, and with winter tires specifically.
#112 of 124 Re: Help requested: Minus sizing for winter tires [goldenone]
Nov 24, 2010 (6:39 am)
Minus sizing is a good idea. First, when changing to a smaller rim size, you reduce cost as the tire is less expensive and you may be able to go to a steel rim.
Second, a narrower tire is better in snow as it has to move less snow out of the way to gain traction.
#113 of 124 Re: Help requested: Minus sizing for winter tires [goldenone]
Nov 24, 2010 (10:27 am)
First on the tire size: The 225/60R16 is a near-perfect match to the 225/55R17; it is only 0.4% larger! 215/65R16 is also a good match, being 1% smaller. What that means is that when your speedometer is reading 60 mph, you would actually be traveling 60.257 mph with the first tire and 59.423 with the second.
I agree with the advantages Rob mentioned as well. I prefer the smaller rim size just because the tires are generally less expensive (sometimes as much as $40 per tire between a 16" and 17" rim). For my '10 Forester, I picked up a used set of those silver-painted steel rims Subaru used extensively during the middle part of the last decade. For winter tires, I also prefer the additional sidewall height to help absorb the deteriorated roads, debris (such as chunks of ice!), etc, and to protect the wheels.
Regarding the Continental tires, they are very good. If you deal with deep snow, I highly recommend Goodyear's Ultra Grip Ice, which are as good as the Conti's on ice and kick the pants off them, Blizzaks, etc., in deep snow.
I have a set of the Continentals on my Escort, and they do me very well. In fact, we are having pretty much the worst episode of freezing rain in the history of Fairbanks, Alaska, right now, and I managed to drive 20 miles to work (then home again) on Monday while most other vehicles were sliding into ditches merely due to the crown on the road! Granted, I had to *work* to keep my car on the road, but the fact that I had that option is a testament to the fact that the tires were giving me much more traction than other rubber on the roads that morning. When I went home that afternoon, I was the *only* FWD vehicle that I saw during that twenty miles. There were the occasional 4WD or AWD (plenty of Subaru's around here!).
Depending on how they end up wearing, I am likely to purchase them again.
#114 of 124 AWD & all 4 tires
Nov 26, 2010 (7:22 am)
On the way to work Wednesday, I picked up something on a Minneapolis freeway that destroyed my left rear tire. This tire was one of a set of four Blizzaks that had only one season on them. Several sources advise replacing at least the two tires on the same axle and preferably all four. Suddenly, a flat tire becomes a fairly large expense. I always do everything that either the owner's manual or my Subaru service department advises, or I exceed it. I am not even remotely "mechanical" but like knowing my car is always at its best and safest. Are there AWD systems out there that are not so "sensitive" to 1/32" or 2/32" difference in tire diameter? My car is a 2003 Legacy L SE, and although I wish I'd known the 2005 GT wagon was coming so soon after, it's a great car, and I love it. Does anyone know of a site where AWD systems are described and compared?
#115 of 124 Re: AWD & all 4 tires [gjksn]
Nov 29, 2010 (8:35 am)
For sure, that is a trade-off for a good AWD system. (cost, mileage being others)
If you think about it, though, even cars with ABS will be thrown off when you have one tire with a different diameter.
If it doesn't, that just means it would be slower to respond to a skid.
If you have a full sized spare, some folks rotate that 5th tire so it gets used up as well, that way a flat doesn't mean 4 replacements.
#116 of 124 Certified??? Really???
Jan 19, 2011 (5:15 pm)
Hi all, just bought an '06 Outback Limited, certified, with just under 30,000. The tires just didn't look right, especially with the recent weather in the northeast. The original Bridgestone Potenzas have about 6mm of tread in the centers, but there is a lot of edge wear, especially on the rears. Also, I had my nephew, who's a Firestone store manager, look at the tires, and he said one of them had sidewall damage due to having been driven with very low inflation. He said the inner side wall was pinched, and is a potential blowout hazard. Any ideas on how I should approach this with the dealer? I know he's going to push back. Also, the air filter was never changed (appears to be the original), despite being replaceable at 30k due to the maintenance schedule. I'm going to check the plugs too, which also should have been replaced as part of the certification process / 30k maintenance. And the brakes seem pretty slim too. Should I take the vehicle to another dealer, or perhaps to the Firestone store, and have them do an inspection and writeup of what needs to be done?
This really bothers me, as I assumed that buying a certified vehicle, at a certified price, meant oil changes only for the first year or so at least. Any advice would be appreciated. Thanks, Dave