Tyre Pressure Confusion

[Shadders]

Hi all

Hoping for some advice.

I have 2017 Leon FR Mk3 with 225/45/17 tyres but the pressure settings seem contradictory.

Sticker on car shows anywhere from 36 to 41 for fronts with light load although not clear what the thermometer is trying to show against the lower pressure.

Most of the time only me & set of golf clubs in boot!

Car went to Seat recently for some work & came out with pressure increased to 38 PSI all round.

What are other people running?

Cheers

 

[SRGTD]

The significance of the thermometer and the downward pointing arrow alongside it is telling you that tyre pressures should always be checked when the tyres are cold. The intermediate setting with the letter ‘I’ alongside it on the sticker in your picture with the is the ‘comfort’ setting (the ‘I’ indicates there’s further information in the owner’s manual); screen shot of the relevant page from your manual below;

I dare say the highest of Seat’s recommended tyre pressures is determined when official mpg and emissions testing is undertaken, as the higher the pressure, the lower the tyres rolling resistance and CO2 emissions and the better the fuel consumption figures will be. However, for some brands of tyre with stiff sidewalls, high tyre pressures may result in a quite hard, non-compliant ride for some owners; hence the alternative ‘comfort’ setting.

In my VW, I have my tyre pressures set a couple of psi lower than VW’s recommended higher setting for a partially loaded vehicle (usually only me in the car) which I find gives a good compromise between comfort and mpg.

 

[Shadders]

The significance of the thermometer and the downward pointing arrow alongside it is telling you that tyre pressures should always be checked when the tyres are cold. The intermediate setting with the letter ‘I’ alongside it on the sticker in your picture with the is the ‘comfort’ setting (the ‘I’ indicates there’s further information in the owner’s manual); screen shot of the relevant page from your manual below;

I dare say the highest of Seat’s recommended tyre pressures is determined when official mpg and emissions testing is undertaken, as the higher the pressure, the lower the tyres rolling resistance and CO2 emissions and the better the fuel consumption figures will be. However, for some brands of tyre with stiff sidewalls, high tyre pressures may result in a quite hard, non-compliant ride for some owners; hence the alternative ‘comfort’ setting.

In my VW, I have my tyre pressures set a couple of psi lower than VW’s recommended higher setting for a partially loaded vehicle (usually only me in the car) which I find gives a good compromise between comfort and mpg.

View attachment 30406

Hi @SRGTD

Thanks for the quick & thorough reply!

In that case will probably stick with 38 as compromise between the two.

Thanks again
Shadders

 

[Seriously?]

Hi @SRGTD

Thanks for the quick & thorough reply!

In that case will probably stick with 38 as compromise between the two.

Thanks again
Shadders

Is yours a hatch? The only reason I ask is that the label on our 2018 FR estate on 17's gives the "comfort" setting (the middle of the 3 options) as 32 PSI all round.

 

[Shadders]

Yes mines the 5dr hatch.

 

[Koulou]

This is a bit awkward.

I also have a 2016 Leon FR Mk3 (pre-facelift) 5dr hatchback with 225/45/17, and the tyre pressures appearing on the sticker on my car are different.

Yep, mine is the pre-facelift version, but it is pretty much the same car, and I wouldn't expect such a difference in the manufacturer's advised tyre pressures.

Currently, I'm running on 36 front - 33 back, which feels OK. I was considering going a couple of PSI lower for a slightly more comfortable ride, plus hoping that my tyres would reach a decent temperature earlier, but reading the above post, it would probably make more sense to go higher. As a note, it is usually just me or me and my missus in the car with minimum luggage.

I've been a bit lost here. Any ideas?

 

[rafletcher]

Different markets may have different springs / dampers - US cars are, to most Europeams, wallowing barges ;-) so I'd go with what the sticker on your car says.

 

[Koulou]

Different markets may have different springs / dampers - US cars are, to most Europeams, wallowing barges ;-) so I'd go with what the sticker on your car says.

Makes sense, mate. Cheers for that.

 

[SRGTD]

@Koulou; The difference in recommended tyre pressures for the 225/45 R17 tyres on your pre-facelift car and @Shadders 2017 (facelift?) car referred to in the original post in this discussion thread could be linked to the launch of the facelift model in 2017. By having higher recommended tyre pressures from 2017, the rolling resistance of the tyres will be less which might help Seat achieve specific CO2 emissions targets they had for the engine range offered in the facelift model fitted with those tyres. Lower rolling resistance of the tyres could also have mpg benefits - if so, it would enable Seat to quote favourable fuel consumption figures too.

 

[SuperV8]

This is a bit awkward.

I also have a 2016 Leon FR Mk3 (pre-facelift) 5dr hatchback with 225/45/17, and the tyre pressures appearing on the sticker on my car are different.
View attachment 30974

Yep, mine is the pre-facelift version, but it is pretty much the same car, and I wouldn't expect such a difference in the manufacturer's advised tyre pressures.

Currently, I'm running on 36 front - 33 back, which feels OK. I was considering going a couple of PSI lower for a slightly more comfortable ride, plus hoping that my tyres would reach a decent temperature earlier, but reading the above post, it would probably make more sense to go higher. As a note, it is usually just me or me and my missus in the car with minimum luggage.

I've been a bit lost here. Any ideas?

There are over 50 different tyre pressure stickers for the Leon mk3 - most starting with 5F0 010 xxx

All linked to PR codes, and will vary depending in vehicle weights, tyre sizes etc...

for example your sticker is 5F0 010 000 BA which is linked with PR codes:

PR:B0A,B0H, B0M,B0N,B1C, B2D,B2F+K8C, K8G+D33,D36, D38,DB1,DB8, DG6,DP7,DS8

and

PR:B0A,B0H, B0M,B0N,B1C, B2D,B2F+K8C, K8G+FM0+DK5

 

[Glosphil]

My 2018 FR shows lower pressures than shown in your photo. Can't remember the exact figures - I'll look later.

 

[Jay5959]

Sticker in my pre-facelift is different (I think, but will check later) but I have the heavy diesel lump in the front of mine. I’m running 41 in fronts and 38 in rears, as per the sticker. The car handles well and is a comfortable drive

 

[Koulou]

Yep, I thought of that after my initial response: a similar car with the same wheelset could be carrying the 2.0 diesel engine, which should be much heavier than the 1.4 TSI. Significantly higher tyre pressures make sense in this case.

 

[SuperV8]

Just FYI while we're discussing tyre pressures,
My sticker below: 5F0010000E in my 2015 2.0 TDI 184 ST FR with 225/45/17 tyres.
I usually stick to 33 all round. Will bump them up on our family holidays.

I'm not really convinced by the higher pressure = better MPG, in my humble opinion it may save a fraction of a % and when multiplied over a million vehicles might make VW look good! But for my car in the real world I doubt I could even measure the difference! when weather/traffic/temperatures/driving style/DPF regen etc make massive differences.

What's more important to me is even tyre wear across their width, and mine seems to be wearing evenly so i'll stick to what i'm doing.

 

[Woody_72]

Just for reference, mine is code B0N and this is the sticker:

 

[SuperV8]

Just for reference, mine is code B0N and this is the sticker:

View attachment 30996

Interesting, same front axle pressures as mine - same engine - but my rear axle is 2psi higher being an ST, and yours a 3 door?
Would you mind sharing your axle weights? Be interesting to see what difference in axle weight would require 2psi extra?

 

[Koulou]

The responses here confirm my feeling that 36 psi at the front seems to be too much, and it gives me a bit of a "harsh" feeling. I'm surprised that some cars come with a 38 or even 41 sticker...

I'm planning to try 34-32. My car came with a pair of "Sunny Sport" tyres at the back, which I really dislike. I hope that slightly lower pressure will work better with them. The plan is either to rotate the tyres and put a pair of fresh Dunlop SP SportMaxx RT (the ones at the front are less than two years old and have minimum mileage) or keep them as they are and change all of them to a fresh (probably a "summer biased" 4-season) set in autumn.

 

[Woody_72]

That was my first thought, mine's a 3 door so the back would weigh less than a 5 door. Where would I find the axle weights?

 

[SRGTD]

That was my first thought, mine's a 3 door so the back would weigh less than a 5 door. Where would I find the axle weights?

Is there a vehicle identification data sticker on the B pillar? My VW has one at the bottom of the passenger side B pillar which includes information such as the VIN code, vehicle weight and axle weight.

 

[SuperV8]

Is there a vehicle identification data sticker on the B pillar? My VW has one at the bottom of the passenger side B pillar which includes information such as the VIN code, vehicle weight and axle weight.

Yes that was the sticker I was thinking about - forgetting it only shows maximum weights. Probably only helpful regarding maximum tyre pressures of 41psi you would expect similar axle max weights?

The weight in running order is available in the manual - but not split by axles,
my ST 184 is 1415kg, the 3door SC is 1350kg and the 5door hatch is 1370kg.
The ST looks like it has arround 100kg higher rear axle max and 140kg GVW difference to the SC - but still the same 41psi! strange.


1980kg GVW (gross vehicle weight)
3580kg GTW (gross train weight)
1. 1020kg =maximum allowed front axle weight
2. 1010kg =maximum allowed rear axle weight