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Trying to find an accurate tyre pressure gauge

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twas_brillig

Jedi Knight
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I found a thread under the 'Restoration and Tools' forum entitled 'tire pressure gauge accuracy' started in 2016 but the forum doesn't appear really active so figured I'd follow up here. I've got probably half a dozen tire gauges, and they all read differently. I'd like to buy a couple of gauges (Christmas is coming) that specify their accuracy: I think I'm running our street legal Meyers Manx dune buggy clone fronts at 18 psi; but the gauges I own imply it could be 15 through 21 psi.
Michelin sells their MN-12279 and advertises that "Gauge accuracy is +/- 1% plus 0.5 PSI ". I figure 1% of 30 psi is .3 psi so they're claiming an accuracy of +/- .8 psi. Snapon advertises 1% accuracy for all their gauges (.3 psi at 30 psi), but I'm bothered that it's the same claim for the entire assortment: stick, digital, dial.
Andy suggestions as to suppliers that specify an accuracy? Thanks, Doug
 
Good ole Milton brand. Been around forever and USA made unless they have been gobbled up recently by a holding company and shipped offshore like nearly every thing. Don't know if they are precisely accurate but they are pretty much indestructible.

Kurt.
 
https://www.leevalley.com/en/garden/page.aspx?cat=2,42194,76255&p=76104
I just picked up several of the 'cheap' version and one of the 'less cheap', as I was concerned that the 'cheap' ones might have trouble reaching the tire stems in a few cases.
I've only found Snap-On and a Michelin gauge that claimed a specific accuracy; these tyre gauges are less costly and claim +/- 1% accuracy. I haven't opened them as they'll be stocking stuffers for Christmas so haven't done a comparison, but have my fingers crossed. Doug
 
The accuracy they quote is relative to full range. If full range is 0 to 100psi and the accuracy is +/- 1%, the accuracy is +/- 1 psi over the full range.

Marv J
 
They have the same +/- 1% standard for both the 100 psi and the 150 psi gauge. I'm assuming that the +/- 1% applies to the specific pressure (i.e. 30 psi means +/0 .3 psi) being measured. If it was measured only at the full pressure, then presumably (me presuming) then they'd specify +/- 1 psi for the one gauge, or +/- 1.5 psi for the 150 psi max. Notice all the 'presumes' in here. Come post Christmas, I'll borrow a couple of them back and do some comparisons. Doug
 
Healeysince59 said:
The accuracy they quote is relative to full range. If full range is 0 to 100psi and the accuracy is +/- 1%, the accuracy is +/- 1 psi over the full range. Marv J
Click to expand...
True in my experience. That's why you don't want to use larger ranges than you need.
 
Finally smartened up and dropped Milton a note last week, asking about their accuracy. I'll report back if/when I get a reply. And they do identify if the tire gauge was manufactured in the USA (found one; the rest I looked at were off-shored); couldn't find any accuracy info though. Doug
 
I am a little confused with this. LBCs are not NASCAR or F1 and the majority of us do not put our cars on the track. What is the concern with tire pressure accuracy. How much does it matter if we are at 25psi or 25.5 psi.
 
I'm not concerned about 0.5 psi; I am concerned over several psi. Plus, we all have our weird little interests (i.e.: hangups). Doug
 
I understand the hang ups thing, but still would say my bigger concern would be consistency, same reading on multiple attempts even if a pound or two off, so that even if your two fronts are at 30 lbs instead of 32 at least they are at the same pressure.

I have several guages. A few years ago a buddy who likes to spend money more than me (if I only hung out with people as cheap as me I wouldn't have any friends) made fun of my cheap "stick" gauge, afterwards I decided to check them against each other, all within a pound. Ranging from real cheap to kinda cheap, and one digital. I don't trust the digital gauges as much as a well built purely mechanical. My own little quirk I guess.

I would also add that the gauges seem to vary more depending on how firm and perpindicular your push on the stem is than the gauges themselves.
 
I agree that a pound or two higher or lower isn't a big deal as long as they are consistent. Air pressure is just a suggestion, suspension settings, driving style, vehicle loading, etc. varies by driver and no 2 are the same. I pay more attention to tread depth over the long run as the most important concern for street use is even wear. As long as the tread wears evenly you are making the best use of the entire tire which I think is the most important aspect of proper inflation.
 
First stop using air and fill with nitrogen if your trying for accuracy
 
Just an update regards my note to Milton: never did hear back as to which (if any) are manufactured offshore or USA; never heard back as to their accuracy. Doug
 
Googled Milton and they are pretty proud of being made in the USA. All I know about them is that they have been making tire tools for all my adult life. I always liked them and go out of the way to buy Milton.

Kurt
 
Bill - had a look at your jbtools web-site michelin gauge, and it's the same one that I'd found earlier in this process: "Gauge accuracy is +/- 1% plus 0.5 PSI"
I'm not too hung-up on our LBCs as I can find recomendations for tire pressures and figure that the recommendations (as well as the gauges) are somewhat 'more or less' as there are a lot of factors in determining 'best'.
My primary concern is our dune buggy - those 7" rims and tires are sure a lot wider than the original VW 4J x 15 rims 5.60 bias ply. Life is too short and mileage per year too low for me to figure out what pressures should be, based on tire wear. I'd done some testing using a hardware sourced laser temperature reader to measure temperatures across the tire tread and varying pressures as I drive down the highway. I also borrowed a tyre pyrometer from a racing buddy and did the same - in both cases, I did not get meaningful results. This could be a function of the stiffness of the radial belt and sidewalls, but I'm buffaloed as there should have been a measurable difference in temperature across the tire tread (3 measurements; centre and outer). I'll try again when the flowers bloom again next year, and move my outside measurement in an inch and maybe I'll get some info that way. Whether or not my tyre gauge was accurate for these tests wasn't as relevant as being repeatable - as pointed out by others.
However, I'd like to have an accurate result so that if I learn something and report it, then the tire pressure results will be meaningful.
And I'm gong to try the samething with our 3000; not sure if the wee 165s (?) that we have on the Yellow BE are wide enough to have a temperature differential....
Later, Doug
 
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