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  #1  
Old 07-13-2015, 07:24 PM
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Proper PSI

265/50R20 Goodyear Fortera HL's on a 2015 Altitude. I like a more firm ride. I see that max PSI is 51 on these guys. Right now they're at 37 and they feel blah. How high do you guys think I can go without getting dangerous?

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Old 07-13-2015, 07:34 PM
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Re: Proper PSI

I ran them at 38 psi cold which got them up to about 41 psi hot on the highway. I personally wouldn't go higher. That includes on my current Nitto NT421 which I peg at 37 psi cold.
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  #3  
Old 07-13-2015, 07:36 PM
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Re: Proper PSI

I run mine at 36 psi cold. They feel firm enough for me.
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Old 07-14-2015, 09:40 AM
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Re: Proper PSI

51 psi... no!
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Old 07-14-2015, 04:10 PM
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Re: Proper PSI

I believe that 51 psi is the max COLD inflation pressure, which if the case like most tires you could exceed when running at highway speeds--although I'd avoid risking it at high speeds in Ariz, Nev, etc. where temps are way over 100.

I run Michelin LTX MS/2 at 40 psi. They go higher on the highways, but the ride fits my preferences more than a lower pressure.

Other than staying away from max cold inflation pressure, "proper PSI" depends on your tastes, whether you are loading up the vehicle [bump pressure to cut heat], etc. There isn't a magic one size fits all value.

37 is a tad low, try 40-41 using a good guage and keep an eye on them with the tps monitor as you drive.
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Old 07-15-2015, 01:29 PM
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Re: Proper PSI

This is the first car I have ever owned where the manufacturer recommends the same PSI across all avail tire sizes (18" vs 20"). Usually the PSI requirement increases as the sidewall shrinks. This is also my first American car as well. So I think its a bit weird that the 18" stock size recommends 36 PSI as does the 20" stock size.

That being the case I have not played around all that much with the PSI on my stock overland 20", and have been running it at 36 PSI.

I will say that the stock fortera HL would run up to 40-41 PSI on the highway after heating up (TEMP rating of B). I now have the Pirelli Scorpion Verde AS Plus on the car, and they never break 38-39 PSI under the same conditions (TEMP rating of A).

That being the case, I might pump mine up to 38 cold and see if I notice a difference in handling, MPG, etc.
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Old 07-17-2015, 08:36 AM
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Re: Proper PSI

I recently had a road force done, do to some vibration in my tires. In my 265/50 20 they bumped me all the way down to 34 I was running around 40 and for some reason they believed that was way too high.
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Old 07-17-2015, 08:47 AM
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Re: Proper PSI

I've been running mine at 44 psi the last 2 days and I love how they ride. I'm a bit nervous that 44 is too high.
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Old 07-17-2015, 10:03 AM
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Re: Proper PSI

The issue with running at 44psi cold is what they get to when they are hot...you get remarkably close to max and you're likely going to wear the center of your tread faster than the edges and also potentially compromise safety and traction. Tires do have some wiggle room in pressure that allows for some minor adjustments to account for personal preference, but running that much higher than "normal" for a given vehicle and tire is risky, IMHO.
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Old 07-17-2015, 10:58 AM
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Re: Proper PSI

I set mine to 36psi cold.
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Old 07-18-2015, 08:42 AM
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Re: Proper PSI

Quote:
Originally Posted by antsjeep View Post
I set mine to 36psi cold.

Same here
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Old 07-18-2015, 09:43 AM
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Re: Proper PSI

Quote:
Originally Posted by overlanding View Post
Same here

36 psi here as well.
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