Tire pressure - range between 4 tires?

WestCoastDan

WestCoastDan

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I didn't see the answer posted on the many previous threads & posts on this subject, so here goes.

What is a realistic range between high & low pressures between all 4 tires?
Meaning, lets say if I measure all 4 tires, and I get 30, 32, 32, & 36 PSI. If measured under the same conditions, at the same time, using the same digital gauge...
Should a 6PSI difference between the high & low readings cause concern or is it OK in the real world?
If 6 is too much that's OK, my example was hypothetical, but what about a 2PSI difference between H & L?

Whats a realistic range to try and maintain?

How many have that much faith in their gauges? :D
 
6 PSI is probably too big a difference but I'm sure there is worse out there with many drivers/owners not noticing anything.

As for "faith in the gauges", I don't have much. I'd be surprised if a gauge didn't read consistently from tire to tire but I'm never surprised to find that two different gauges read two different PSIs on the same tire.

Some time in the past I compared all the gauges that I had access to, one TPMS in a Pontiac, a couple digitals and maybe a half dozen not digitals. None of them read the same. IIRC, the biggest difference was 10 or 12 PSI.
 
I recently bought an inexpensive digital gauge. It wasn't as much of a choice as it was a necessity because I threw that old stick version acrosss the garage last month after not being able to read it any longer. It sure as hell is easier to read the digital one; not that I trust it any more than the old one, it just eliminates ME as the potential error when reading it.:ROFLMAO:
 
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I like dead nuts and I agree 6 is too much but 1-2 is margin of error.

If you're circle track racing you set different pressure on all four tires since you're always turning left.

I bought an air down kit with screw adjustable valves...makes it fast easy and accurate.

-Mac
 
I tried to get within 1-2 psi of each other when I air back up to around 25. I tried to get them within a closer range when i air down to about 6 psi. Amazon has a decent digital pressure gauge for 3 of them for 17 bucks. Reasonably accurate.
 
macleanflood said:
I bought an air down kit with screw adjustable valves...makes it fast easy and accurate.
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So did I, a couple times, and stopped using them due to them being so inconsistent. One of them, Coyote I believe, has a good reputation and came highly recommended but I wasn't seeing consistency from them either. I was at a 4x4 show and saw their rep selling the same deflator I have so I ran out to my Jeep and grabbed them and had him set them using his super-duper adjuster. They were no better and just as inconsistent after he set them too. I stopped using them and rely on my Currie deflator with the big gauge.
 
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When I'm inflating them, I stop when they're at my desired pressure so they're gonna be within 1psi.

If I'm just checking, I don't pay much attention to the range between tires, but if I catch one 6psi low I'm going to air it back up to 25.
 
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I don't trust my ability to read a stick-type gauge repeatedly (from tire to tire, for instance), thus i tend to overinflate, and air down to the desired pressure.
The new digital gauge has a release button that allows for this approach, and can read down to a tenth of a PSI, which is far more accurate than my old gauge and eyes.
 
If one side is in the sun and the other in the shade I’ve seen them several pounds different. Seems like the bigger the tire the more this is true.
 
You check em cold in the morning, in the shade, and set them to where you want them. Expect a 1-2 lb increase as they get warm from driving or sitting in the sun and adjust accordingly.
 
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Just be sure your gauge is a good, accurate gauge…

image.jpg
 
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Brianj5600 said:
I don't worry about having a accurate gauge as long as it is repeatable. The vast majority of us don't run recommend pressure on road and definitely not on the trail.
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This is very much the best advice. Make sure you get the same read every time you use the gauge. I have seen some gauges vary as much as +/- 3psi on repeatability checks. Mechanical dial gauges you will need to tap lightly as you use them, especially if it’s a cheap or old one. Fluid filled gauges you’ll need to burp first. Digital are ok, but they don’t like moisture, and if you use beyond their range, you probably just damaged the pressure membrane.
 
A gauge with less range will be more accurate and easier to read.
In addition to a 0-40, I use a low pressure (0-20) for offroad.
 
LONGJP2 said:
A gauge with less range will be more accurate and easier to read.
In addition to a 0-40, I use a low pressure (0-20) for offroad.
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Only true for digital. For all analog gauges they are a percentage based on readings at 20%, 50%, and 80% full range.

For scaling, lower ranges will have more resolution. A 60psi gauge usually has 1psi divisions, and is ideal for most auto use.

For most people, really just need to make sure it is repeatable. If you have a gauge, like mine above, you can characterize your tire gauge before use each time.
 
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