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Discussion Starter #1
This has been bugging me for a while.

My 1997 OBW manual recommends 29psi Front/28psi Rear inflation for the tires...

But obviously with 139,000 miles on the car the tires have been replaced at least once (most likely twice...I bought it used with 127,000).

The tires currently on the car recommend 35psi all around.

I emailed SOA and they said: "Good question...we don't have an answer, you'll have to decide for yourself." So I guess I stumped them.

Anyway, what psi do the rest of you OB owners keep your tires inflated to?

Currently I'm still using the Subaru numbers, but the tires look very under-inflated that way, especially during these freezing winter months. 28 days out of 31 here in January were below 30F. Brrrr.
 

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As I mentioned in another thread, I run 32psi all round. My tyre dealer recommended 36psi, which was a little too firm for me. Apparently Subaru down here in Australia also recommend 35-36psi as well.

Running higher than recommended tyre pressures seems to help reduce tyre wear.
 

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Well, I had mine very low, about 29psi all around.

Got ~260 miles on my last tank (about 13 gallons) so thats not so good.

I just filled the tank and upped the pressure in all 4 tires to 35psi. I will post again the next time I fill the tank and let you know if the psi change had any effect on mileage, I'm pretty sure it will.
 

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32-34psi depending on how I feel. Less than this and it impacts on handling and fuel economy. Under 32psi and it feels sloppy and the tyres squeal around corners when pushed hard.

I have used nitrogen fill which is supposed to give longer tyre life and better ride. I use 30-32 with nitrogen fill as the tyres don't heat up as much with nitrogen fill, so the cold to hot pressure diff is less. I've stopped using it as it's a pain to go to the places that sell it.
 

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All I have to say is remember the Firestone/Explorer issue. Always do what the car maker says, not the tire maker. If it says on the vehicles load guide/rating on the door area for 30 psi all around, do it. The tire itself usually gives you max. inflatable psi, not recommended driving psi. Always go by the vehicle suggested psi. Brian
 

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That's a good point.

If I live through this tank, I will drop the pressure down closer to the Subaru specs.
But I'm going to keep them at 35 for this tank at least just so I can get an idea if more pressure = better mileage.
 

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I will have to say that normally I put 32psi all the way around and have never had drivability problems. Of course I have a MY02 OBS though. Brian
 

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The Firestone problem was due to underinflation issues. I would still be inclined to go above the recommended Subaru psi as this is a little soft for general driving and better for fuel economy. There is also less heat build up when running higher pressures so there is less stress on the tyre. Heat build up is a major cause of tyre failure.
 

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IMO the Firestone issue was do to the FACT that Firestone makes crappy tires and that Ford makes crappy vehicles, case and point the Exploder :rolleyes:

Anyway, the tech at Stan Olsen Subaru told me to put in 36 psi and I'm fine with it. The stock RE-92's (read: JUNK) have VERY flexible sidewalls and don't ride stiff even with that high of pressure. I really think that the air pressure depends of what kind of tire you have and not nessicarily what size of tire. Most cheapo tires will have softer sidewalls where the higher grade tires will have stiff. Henceforth higher quality tires will perform well at most pressures whereas junker tires will need to be pumped up to do their best. Just a litle insightfor anyone interested :D
 

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Originally posted by FMGreen
...The tires currently on the car recommend 35psi all around. ...
If you're going by the number on the sidewall, that's the max cold pressure. It does not mean that's what you should run at. Although 35 is quite low for a max pressure - what tires are these?

As for what the car manufacturer recommend, regard that as a minimum. It's usually spec'd for ride comfort, not handling. For most cars, adding 3 psi or so works wonders, for most H-rated all-seasons.

I do 32f/31r on the oem (exceedingly crappy) Mich XWX's, as well as the current Sumi Srixon4 & previous BS re930 215/65/15's.

If anyone has any ideas as to whether the 1psi lower rear is required - I'm assuming it's for the health of the center diff - I'd like to hear them.
 

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I think its common to see that the recommended tire pressure for half load on the front is always higher, due to the extra weight of the engine/transmission up front. I wonder what the recommended tire pressure is on BMWs, they usually have a very close 50/50 front/rear weight distribution.
 

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IIRC, our FWD '92 Mazda Protege was 30f/30r, ran it at 32/32. Current '97 Miata is 26/26, running at 28/28 on BS re950's, but 32/32 on Toyo T1-S's. And '03 2wd Tacoma 29/29, running at 32/32.
 

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Discussion Starter #15
Well the results are in, 35/35 offered no improvement on gas mileage.
The ride was, as expected, A LOT stiffer than it had been at 28/28.
My ribs felt every pot hole and we've got a ton of them this time of year.

I dropped the pressure to 33/32 with this tank. Already I've gotten 54 miles and my fuel needle has barely moved past the F, but to be fair, most of those miles were country roads above 50mph. Definitely not start/stop city driving.

The ride is slightly smoother, especially in the rear, I get a lot more bounce back there after hitting bumps.

I am certain that my rear suspension is shot to ****, I often hear big bangs and clanks and knocking sounds coming from back there.

Any advice for replacements back there?
 

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ah nice, thanks. i know ive read a lot of good stuff about those ones.
are those prices at tirerack average? high/low? $66ea front, $58ea rear...

also, is it bad to replace just the rears and not do the fronts? or would it be worth it to do all four at once, for continuity?
 

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FMGreen said:
ah nice, thanks. i know ive read a lot of good stuff about those ones.
are those prices at tirerack average? high/low? $66ea front, $58ea rear...

also, is it bad to replace just the rears and not do the fronts? or would it be worth it to do all four at once, for continuity?
Sorry it took me so long to respond, I was out Friday and the weekend xcountry skiing and have been trying to catch up with work every since.

I believe that is about as good a price as you will find. Tirerack is pretty good with that.

I am researching that issue for my Legacy as well, as the front seems to be all that needs replacing. I would assume that doing all four would be best, but I can't think of a reason why you would HAVE to. I will let you know if I find a definitive answer.
 

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Discussion Starter #19
Cool.

Also, my tank at 33/32 gave me over 20 more miles than 35/35 or Subaru spec 29/28.
I did 280+ and my low fuel light didn't even come on.

I'm pretty sure it is because most of those were highway miles. But I also drove it pretty hard, a lot of high speed (+75mph) cruising, and a lot of quick acceleration (passing, and just having fun). So I'm happy with 33/32, plus the ride feels a lot more comfortable.
 

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"CLANK, BOING, BANG *bounce*bounce*bounce*"

My rear suspension is getting unbearably bad now. I definitely need to replace within the month.

No one really answered my question a few months back:
Is it bad to replace just the rear struts and leave the front as-is? The front seem fine to me, and I'd rather not spend an extra $140 to buy a new front pair as well.

I will probably order KYB-GR-2s from TireRack.
Is a strut install something best left to a professional? Or could I give it a shot with a couple jacks and a nice socket set?

141k miles on what I assume to be the original set...
 
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