[Steve H]

Hi all,

Just a quick one, I've done nearly 900 miles from new now and due to some stiff bumps and road noise thought I'd check my tyre pressure when I got to work today. The plate inside the drivers door says 36psi but when I double checked with the manual that says 32psi. I'm running 195/65/R15's. Anyone know which pressure is correct?

When I checked them about 20 mins after an hours drive in the pouring rain (they didn't feel warm to touch) they were all showing around the 41psi mark but I'd had no warnings on the dash. I'll check them again tonight before I head home after Toby has been stood round for 7 hours.

Thanks

Steve

[Surferdude]

Only check them dead cold.  Or no more than a mile into your morning drive.
36 psi will give you the best handling/ wear result.

I must admit I've never seen a difference between the placard and the manual before.

[Steve H]

Well finished work and all tyres still showing 41psi so I've dropped them down to 36psi now. At least it doesn't feel like I'm hitting a house brick if I go over a cats eye....... 

[The Gonz]

I've always seen even wear at my preferred 41 all 'round, and I won't mind running over the whole cat.

[Phil №❶]

Oi, 

[xiziz]

I run mine at 3bar cold. 3.2bar when i get home after my commute. Which is what, 43psi? Think the fronts look like there bulging when using even 2.8, the factory reccomended looks like im running with four flat tyres.

[Surferdude]

Radials are supposed to bulge. Their design is intended that way to maintain the correct footprint on the road. If you inflate them to the point where there is no bulge, you are removing most of the flexibility from the sidewalls which negates the benefits of having radial tyres.

[CraigB]

I run mine at 3bar cold. 3.2bar when i get home after my commute. Which is what, 43psi? Think the fronts look like there bulging when using even 2.8, the factory reccomended looks like im running with four flat tyres.

Factory placard standard recommendation should be 32 psi on mine though 38 psi is what I like to run with the 18's, the tyre shop who fitted mine had them all on 44 psi which is probably fine but very hard to ride on.

[Surferdude]

Incidentally Gonz, you have a diesel and I'd agree with the 40 psi, at least in the front, for the heavier engine.
The OP hasn't given car details and I maybe wrongly,  assumed petrol.

[Surferdude]

I run mine at 3bar cold. 3.2bar when i get home after my commute. Which is what, 43psi? Think the fronts look like there bulging when using even 2.8, the factory reccomended looks like im running with four flat tyres.

Factory placard standard recommendation should be 32 psi on mine though 38 psi is what I like to run with the 18's, the tyre shop who fitted mine had them all on 44 psi which is probably fine but very hard to ride on.

If they're 225/40R18, then 43 or 44 is correct.

[Doggie 1]

Radials are supposed to bulge.

I must have really big radial undies then.   

[Surferdude]

Radials are supposed to bulge.

I must have really big radial undies then.   

In which case you've used too much compressed air. 

[Doggie 1]

Radials are supposed to bulge.

I must have really big radial undies then.   

In which case you've used too much compressed air. 

Trust me, my air isn't compressed!   

[CraigB]

If they're 225/40R18, then 43 or 44 is correct.

I shall return them back to that pressure then on your advice Trev they felt like driving on the Flintstone wheels though

[Surferdude]

If they're 225/40R18, then 43 or 44 is correct.

I shall return them back to that pressure then on your advice Trev they felt like driving on the Flintstone wheels though

No. Sorry. I've mislead you. Those are the maximum allowable pressures for that size. I thought you were happy at that pressure. If you're running them down in the high 30s, that's fine. Personally,  with your car, id be happy at 38psi max.

[CraigB]

If they're 225/40R18, then 43 or 44 is correct.

I shall return them back to that pressure then on your advice Trev they felt like driving on the Flintstone wheels though

No. Sorry. I've mislead you. Those are the maximum allowable pressures for that size. I thought you were happy at that pressure. If you're running them down in the high 30s, that's fine. Personally,  with your car, id be happy at 38psi max.

Cool! thanks the tyres maximum is 50 psi as written on the sidewall.

[Surferdude]

^Wow. A bit more than the AT&RA Manual says.

[CraigB]

^Wow. A bit more than the AT&RA Manual says.

I suppose being 92W and extra load rated they're a bit higher

[The Gonz]

Radials are supposed to bulge.

I must have really big radial undies then.   

In which case you've used too much compressed air. 

Trust me, my air isn't compressed!   

Doggie's used to runflat(ulent)s.

[xiziz]

Radials are supposed to bulge. Their design is intended that way to maintain the correct footprint on the road. If you inflate them to the point where there is no bulge, you are removing most of the flexibility from the sidewalls which negates the benefits of having radial tyres.

Interesting, I just looked at the max(3.5bar), and dropped it down a bit after some quick research I found that a lot of people seem to prefer using a high pressure around here, lots of cornering. Summers are 205/55/R16 91H and the winters are 195/65/R15 91T. 2.2bar(32psi) is recommended. I think I'll try and drop them down a bit after sundown, got 250km driving tomorrow to test it out on. What would you put them at?

Edit: Put 2.6(~38psi) front and 2.4(~35psi) rear.

[Surferdude]

Radials are supposed to bulge. Their design is intended that way to maintain the correct footprint on the road. If you inflate them to the point where there is no bulge, you are removing most of the flexibility from the sidewalls which negates the benefits of having radial tyres.

Interesting, I just looked at the max(3.5bar), and dropped it down a bit after some quick research I found that a lot of people seem to prefer using a high pressure around here, lots of cornering. Summers are 205/55/R16 91H and the winters are 195/65/R15 91T. 2.2bar(32psi) is recommended. I think I'll try and drop them down a bit after sundown, got 250km driving tomorrow to test it out on. What would you put them at?

Edit: Put 2.6(~38psi) front and 2.4(~35psi) rear.

38-40 front and 35-36 rear should be fine.

[Surferdude]

^Wow. A bit more than the AT&RA Manual says.

I suppose being 92W and extra load rated they're a bit higher

Yeah. The EL would do it.   

[sundiz]

What would you put them at?

Edit: Put 2.6(~38psi) front and 2.4(~35psi) rear.

I have 195/65-15 in summer and winter tyres. I use 2.5 bar in both. Runs much better and I can see a difference in fuel consumption when compared to 2.2 bar. If I have full load in the car and trailer then 2.7 in the rear. Winter tyres I usually set to 2.7 bar when I put them on due the drop of pressure in the cold. When it gets colder, I'll rise it up to 2.5 bar.

[Steve H]

Incidentally Gonz, you have a diesel and I'd agree with the 40 psi, at least in the front, for the heavier engine.
The OP hasn't given car details and I maybe wrongly,  assumed petrol.

Should be showing in my signature thing? No worries as no harm done. 1.6 diesel, should I top the front 2 up to 38psi in that case?

[Surferdude]

Incidentally Gonz, you have a diesel and I'd agree with the 40 psi, at least in the front, for the heavier engine.
The OP hasn't given car details and I maybe wrongly,  assumed petrol.

Should be showing in my signature thing? No worries as no harm done. 1.6 diesel, should I top the front 2 up to 38psi in that case?

Couldn't se it before. It's there now.
Yeah. 38.

[pidim]

I run my car at 36 PSI but to be honest, the ride quality of the GD is my biggest disappointment and have never really enjoyed it.

I have tried 32~36 and there is some difference in ride quality but not enough to justify premature tyre wear, so now I stick with 36 all round.  The car ride never settles and jiggles and crashes over expansion joints on bridges and road joins... it's awful.  The tyres are not what you would call low profile either.  In fact I even changed perfectly good tyres to another brand to see if it would help, but nothing much. A friend has a Mazda 3 Maxx and all road test suggests it also has a harsh ride, yet compared to my GD, it's like an S series Merc when I ride in the car.  Well that's my gripe for today   

[Little Mick]

I run 40 psi and since have added just over 10,000km, 62,000km to 74,000km,  to my total tyre wear while running the same tyres since dealer delivery.
On the first set running 40psi since tyres were new and so far the wear difference is very clear.

[The Gonz]

Most have seen me post this before: I've run all 4 tyres at 41psi and two are still original, the other two changed out at 67Mm due to an alignment problem only. 85Mm so far.

[DaveK92]

Hi guys,

I had done some reading regarding the pressure of the i30 and see most people running 36psi, however I see this is on a lot of 16" wheels, today I just noticed my mam's i30 is 15". It's silly that Hyundai recommend 32psi for more or less all their models, even the 1.6 diesel. Her car is also an automatic so is even heavier again. I see the OP of this thread is also on 15s.

Is 36 the same recomendation of 15" as it is 16"? What about for a 1.6 diesel automatic, which is around 200kg heavier (if I'm correct) than the 1.4 petrol manual? As far as I know all tyres on the car are 195/65 R15. I believe max pressure on 16s is around 44psi, on the 15s it's 51 or something, so should I run 38? Higher?

I changed them from 30/31 to 36 all around, it felt a bit more firmer over potholes and manholes but in a good way, it felt more agile and reliable although I only drove about 2-3km so it's early days. Hopefully the economy will increase too as it's hard to resist the power sometimes

[Asterix]

I run 36 psi on 195-65/15, no problems...