Fustrated with tyre pressure...

[huhjared]

ok the story goes like this...
was complaining that my tyre noise is loud on my euro and everyone here thinks its because of my tyre pressure... ok accept that went to buy a tyre pressure guage from supercheapauto and being a cheap ass i bought a pen style one (metal) apparently the better ones among the cheap ones for $7/$6.99...
went to the servo to check my tyre pressure... ok pumped 32 ( as recommended for quietness) then used the tyre pressure with the pen... ITS 36...
confused as it is... went down to pump it to like 28 and it shows 32... to be on the save side... i pumped "32" from the servo which equates to 36 on the pen drove home and checked my neighbour's tyre perssure which is a new corolla... it shows 32... i am like dont think a new car with 4000ks be wrong would it???
which should i trust? servo or pen? if its the servo wont that mean that i was on 40psi for the past 2 weeks??? and that wont be true as the guys who fitted my tyres check over the pressure when it had 40psi and said its all good...

confused confused... going on a long trip to Gold Coast tom morning and wont want the tyre pressure to be wrong eating my rubber on such a trip especially when its spanking brand new...

reason for all the frustration:
just gotten the 2nd hand euro 4 weeks ago and it was supposed to be a comfy car especially when i gotten the lux version... it is embarrassing when people sit in the car and ask why is your "new" car so noisy...

[aaronng]

The pen pressure gauge is CRAP. Return it for a dial pressure gauge instead. The Corolla's pressure reading is useless for your comparison.

[Dy_]

lol dont buy them pen things.

[huhjared]

pffff.... yeah the thing is i spoke to him regarding his tyre pressure and he said its on 32 on his corolla... so wont that be like a standard to follow on the gauge? what about the digital pen one which is like $20 at the warehouse... saw its like $9.90 today when i went there...

[aaronng]

Stay away from the digital shit too. I bought one and it stopped working within 6 months. The dial type is the only one you should trust. I bought the $11 Aunger one from BigW, and when I compared it to a calibrated gauge (complete with serial number and all that shit), it was off by only 0.5 psi! It's been 2.5 years and it still reads as good as when I bought it.

[itshk]

try another servo :)

[huhjared]

I bought a dail tyre and i broke in like 2 days... hahahaha... paid $9.99 for that... the needle inside popped out... arh... anyway could you say whats the difference between your dial gauge vs the digital gauge at the servo? if you pressed like 32psi on the servo what would be be roughly reading out from your gauge?

[Crapdaz]

go to a local petrol station (not the big name petrol stations), they will have a manual air gauge pump so you can see the proper reading.

i never use the automated sh*t, trust the manual stuff all the way.

What tyres are you running?
and does it sound like your tyres/road noise(humming sound) or suspension (rocking)?
Have you checked whether or not you have rocks stuck inside your tread?

[huhjared]

humming and bumpy... so i guess its due to the high tyre pressure...

[VTECMACHINE]

I've been driving my Dad's Euro lux for the past few days! Heaven I tell you.
Come to think of it, the stock tyres are a bit loud. Meh, beats a stripped out DC2R for noise. The 17's on the Euro make it a nice firm/harsh ride also, compared to the ones on 16's ive driven.

[CB7_OWNER]

When you mention the automated pressure inflators at servos... i noticed...

Say i inflate the tyre to 36 psi....then i remove the hose,...and to double check, i put the hose on again on the same tyre.. and it starts pumping up from 34psi...soo its lyk soo wtf???

But back to topic, i don't think 3-4psi is goner make much of a difference in tyre noise??

[huhjared]

with the whatever tyre pressure i am running on right now its bump absorbing and quieter maybe 50% quieter than my previous tyre pressure... imagine hearing humming noise on the euro... to me that is like hearing significant tyre noise on a BMW its just not right...

[aaronng]

When you mention the automated pressure inflators at servos... i noticed...

Say i inflate the tyre to 36 psi....then i remove the hose,...and to double check, i put the hose on again on the same tyre.. and it starts pumping up from 34psi...soo its lyk soo wtf???

But back to topic, i don't think 3-4psi is goner make much of a difference in tyre noise??
On my car, there is a very big difference between 34psi and 38psi. 38 is bad enough for me to stop at the side of the road after inflating, just to deflate it back to 36psi!

[Mugen Civic]

humming may come from the tyre uneven wear, not so much like camber wear but that the tyre may not be exactly circle. May not be noticable to the naked eye.

happened to me sometimes due to bad shocks.

Just a thought

[vinnY]

out of curiosity what tyres are on there at the moment?

[huhjared]

supposed to be quiet tyres... goodyear excellence... erm... regarding them being not round... they are brand new... 4 weeks old... yeah...jest came back from the servo with the manual pump things... did 34 psi on the front and 33psi on the back... hopefully would be as quiet as when i got them from the dealer (26PSI) but i doubt so...

[JohnL]

I think it might have been 'Choice' magazine that some years ago did a survey of servo pressure guages, and found that very few were reasonably accurate, and some were very very inaccurate. Don't trust them. The 'pens' are junk. Not all the dial types are good, but it's a better chance than the other types (decent ones probably start around the $50 mark?, but some cheaper ones are probably OK, though the cheaper it is the less likely it is that each individual guage is checked at the factory...).

When I first bought my dial guage I took it to a tyre shop and checked it against a rather flash / expensive looking guage they kept to calibrate their air line guages, and it was within 0.5 psi of that one, which is pretty good.

Even good quality dial types tend to be rather fragile, i.e. the calibration is easily thrown off if you say drop them onto a hard surface. This is why you'll see the more expensive ones fitted with a protective rubber ring around the guage body. I dropped my dial guage and wrecked it, so as an emergency measure I bought a $20 digital guage from BigW, which seems to work acceptably and does at least give consistent readings (though I haven't checked it's accuracy against a known good guage).

If you get a good guage, it's a good idea to get a sturdy container to store it in. I used a tupperware style box and put some foam into the box into which I cut pockets for the guage to sit.

[JohnL]

humming may come from the tyre uneven wear, not so much like camber wear but that the tyre may not be exactly circle. May not be noticable to the naked eye.

happened to me sometimes due to bad shocks.

Just a thought

A bit sceptical on that one.

My understanding is that tyre noise comes from the tread pattern itself (some patterns being inherantly noisier than others, tending to be noisier with the patterns that give better steering response etc as used on 'high performance' tyres...), but can be excacerbated by stiffer sidewalls or higher inflation psi.

I suspect (meaning I'm only speculating) that this might be because more noise is transferred through the stiffer sidewall (being actually stiffer or effectively stiffer due higher psi) into the suspension and steering linkages, and from there into the chassis...?

[JohnL]

i am like dont think a new car with 4000ks be wrong would it???

My mum's Mazda came from the dealer (new) with 32psi on both left side tyres and 52psi on both right side tyres....