Tyre Pressure Gauge

[rjn]

Thought I had already posted this last night, weird, anyway, anybody got a recommendation on a tyre pressure gauge?

Nothing too ott, but a good quality one preferably round dial with short hose and pressure release button. Pressure up to at least 50psi would also be good.

[Paradoxx]

Yep that's what you should be looking for... not a digital one or anything with too much plastic.

They are all pretty much made in the same manner so just buy one that suits your budget.

[SavageF6]

Got a little one from Autoburn for $10. The dial is a little bigger than a large watch face, and reads to 50psi (60? dunno). Either way, each mark around the dial is 2psi, making 1psi readings in my range of 30-40psi a piece of piss. Seems accurate enough, as good as any digital reading at a servo.

Might be too winky-dinky for your requirements though.

[Cro]

Got one from one of those snap on trucks for $60.

Got everything you asked for, except goes to 60psi.

[rjn]

Got one from one of those snap on trucks for $60.

Got everything you asked for, except goes to 60psi.

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Perfect! thanks for the info Cro.

It just had to go to at least 50psi, 60 is no problem.

I have a go kart gauge but it only goes to 40psi, which is fine as I don't run over that except if you accidentally pump them up to over 40 and then check, it screws the internals in the gauge, learnt that the hard way

Any more info, part number, where to buy (not sure about flagging down a snap on truck??)??

Might try my local mechanic.

[Cro]

Sorry it's been a couple of years since I've bought it.

It's a round one, with a tube hanging off it. The pressure release valve is ontop of the guage itself, and the guage is covered with a black rubber ring.

Ask your service dept/mechanic/tyre mob when they get visited by the snapon truck.

I was driving along when I saw one up in the distance, caught up to it and flashed. He was more than happy to pull over, especially after spending a couple hundred bucks. It's like a bunnings in there, lots of toys that you'll never ever use

[SavageF6]

mmmmm mobile bunnings...

[Iconic Bionic]

From some tyre nut:

Tyre pressure and gas-mileage.

For the first two years of our new life in America, I'd take our Subaru for its service, and it would come back with the tyres pumped up to 40psi. Each time, I'd check the door pillar sticker which informed me that they should be 32psi front and 28psi rear, and let the air out to get to those values. Eventually, seeing odd tyre wear and getting fed up of doing this, I asked one of the mechanics "why do you always over-inflate the tyres?" I got a very long and technical response which basically indicated that Subaru are one of the manufacturers who've never really adjusted their recommended tyre pressures in line with new technology. It seems that the numbers they put in their manuals and door stickers are a little out of date. I'm a bit of a skeptic so I researched this on the Internet in some of the Impreza forums and chat rooms and it turns out to be true. So I pumped up the tyres to 40psi front and rear, as the garage had been doing, and as my research indicated. The result, of course, is a much stiffer ride. But the odd tyre wear has gone, and my gas-mileage has changed from a meagre 15.7mpg (U.S) to a slightly more respectable 20.32 mpg (U.S). That's with mostly stop-start in-town driving. Compare that to the official quoted Subaru figures of 21mpg (city) and 27mpg (freeway) and you'll see that by changing the tyre pressures to not match the manual and door sticker, I've basically achieved their quoted figures.

So what does this prove? Well for one it proves that tyre pressure is absolutely linked to your car's economy. I can get an extra 50 miles between fill-ups now. It also proves that it's worth researching things if you think something is a little odd. It does also add weight to the above motto about not trusting forecourt pressure gauges. Imagine if you're underfilling your tyres because of a dodgy pressure gauge - not only is it dangerous, but it's costing you at the pump too.

What's the "correct" tyre pressure?

How long is a piece of string?

Seriously though, you'll be more likely to get a sensible answer to the length of a piece of string than you will to the question of tyres pressures. Lets just say a good starting point is the pressure indicated in the owner's manual, or the sticker inside the driver's side door pillar.I say 'starting point' because on every car I've owned, I've ended up deviating from those figures for one reason or another. On my Subaru Impreza, as outlined above, I got much better gas mileage and no difference in tyre wear by increasing my pressures to 40psi. On my Honda Element, I cured the vague handling and outer-tyre-edge wear by increasing the pressures from the manufacturer-recommended 32/34psi front and rear respectively, to 37psi all round. On my Audi Coupe I cured some squirrelly braking problems by increasing the pressure at the front from 32psi to 36psi. On my really old VW Golf, I cured bad fuel economy and vague steering by increasing the pressures all-round to 33psi.

So what can you, dear reader, learn from my anecdotes? Not much really. It's pub-science. Ask ten Subaru Impreza owners what they run their tyres at and you'll get ten different answers. It depends on how they drive, what size wheels they have, what type of tyres they have, the required comfort vs. handling levels and so on and so forth. That's why I said the sticker in the door pillar is a good starting point. It's really up to you to search the internet and ask around for information specific to your car.

The Max. Pressure -10% theory.

Every tyre has a maximum inflation pressure stamped on the side somewhere. This is the maximum pressure the tyre can safely achieve under load. It is not the pressure you should inflate them to.

Having said this, I've given up using the door pillar sticker as my starting point and instead use the max.pressure-10% theory. According to the wags on many internet forums you can get the best performance by inflating them to 10% less than their recommended maximum pressure (the tyres, not the wags - they already haves inflated egos). It's a vague rule of thumb, and given that every car is different in weight and handling, it's a bit of a sledgehammer approach. But from my experience it does seem to provide a better starting point for adjusting tyre pressures. So to go back to my Subaru Impreza example, the maximum pressure on my Yokohama tyres is 44psi. 10% of that is 4.4, so 44-4.4=39.6psi which is about where I ended up. On my Element, the maximum pressure is 40psi so the 10% rule started me out at 36psi. I added one more to see what happened and it got better. Going up to 38psi and it definitely went off the boil, so for my vehicle and my driving style, 37psi on the Element was the sweet spot.

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[Cro]

I wouldn't trust anything an American says about tyres...

They usually want big milage rather than performance.

[rjn]

For anyone who is interested, bought one of these a couple of weeks back. Probably the same as Cro's. Works well.

Dangerous to know you can buy online from Snap On........