tyre Pressures - conflicting Info

[richtung]

Morning guys,

Before someone flames me, ive done a search and im still confused!

Looking to take delivery of a pair of Michelin PS3's (225/40/18 XL 92Y) to go on the fronts of the ED30. The rears will have Vredestein Ultrac Sessanta's.

Now, when it comes to tyre pressures, I used to fill to 30 PSI all round. After having 4 wheel alignment carried out, the technician advised that I should always fill to whatever the manufactures recommends. In my case, its 36PSI front and rear (IIRC).
However, just been looking at a couple of online tyre pressure guides such as:

http://www.hiqonline.co.uk/Expert-Advice/Tools-and-Reminders/Pressure-Guide/
http://www.tyresafe.org/tyre-safety/tyre-pressure-check
http://www.national.co.uk/information/tyre-pressure.aspx#tyrecheck

They all indicate that I should be running (for normal loads):

Front: 44 PSI
Rear: 29 PSI

You can clearly see a difference in what is advised compared to what VW recommend, hence my new found confusion 

Im going to give the Michelin helpline a ring to see what they recommend.

What pressures do you guys recommend as "optimal" pressure for a regular driver after maximum fuel economy, max grip and minimal wear?

Thanks in advance

Rich 

[rich83]

Somewhere around 2.1-2.3 bar is about optimal for normal road use. 

[Tortaruga]

I do mine to the pressures in the fuel flap. I always assumed the car maker knows best, however you've sown a seed of doubt as to whether this applies when you fit new tyres made by a different manufacturer than those supplied oem.

[xjay1337]

I run 36 all around, I prefer how it handles, rides, is more economical, and does not effect my tyre wear.

[richtung]

I do mine to the pressures in the fuel flap. I always assumed the car maker knows best, however you've sown a seed of doubt as to whether this applies when you fit new tyres made by a different manufacturer than those supplied oem.

This has what got me thinking. Im not sure what brand of tyre the ED30 left the factory with but im confident that tyre technology has advanced since 2007 so would 7 year old info be applicable to modern tyres?

Rich

[Tortaruga]

^^^My thoughts entirely. Will be interested to hear what Michelin have to say-keep us posted!

[MikeA]

Just swapped to my winter tyres on my ED30, Vredestein WINTRAC XTREME 225/45/17 and the vredestein web site advises front 2.9 bar (42psi)  rear 3.3 bar (48psi)    also checked Michelin as i have PS3's summer tyres and they advise 29 psi all round or front 33.4psi and rear 40.6psi for motorway driving.

Well that hasn't really helped with your question but its trust the tyre manufacturers figures or VW figures from the hand book (filler cap cover)

[richtung]

^^^My thoughts entirely. Will be interested to hear what Michelin have to say-keep us posted!

Well, just got of the phone to Michelin. The bloke I spoke to recommended to follow the manufacturers guidelines on tyres pressures.

I think a call to VW uk to see if they have any updated data in regards to tyre pressures...

Rich

[JigBake]

Im running Michelin PS3's all round. 38psi in every corner for me.

[richtung]

Im running Michelin PS3's all round. 38psi in every corner for me.

Just got off the phone from VW customer services. The agent handling my call put a query to their technical department and they came back with 38 PSI front and rear.
I guess the data has been updated since the 2007.

Jake - where did you get the figure 0f 38 PSI from out of interest?

Thanks

Rich

[rich83]

38 is too high in my opinion!

[Homer]

35 PSI all round. I would say that 38 or higher is way too much, I have tried it and car does not appear to handle as well as when its around 35 PSI. If the tyre is the same spec/size as your original ones supplied with the car why would the pressure have increased?

If someone goes for different size alloys/tyres then I could see why the tyre pressure would be different. I think we all have a habbit of overthinking when it comes to our cars.. sometimes I think some of us need therapy to be honest including myself...

[jonnym]

Mine say 35 but that's on 7.5J rim but at 225/40. Although a small different, surely that's needs to be considered?

[edd666999]

I run 33 all round. Tried higher and lower and this felt right.

[Scottymon]

I run 38-40 all round on 225/40/18 F1 AS2's soon to be Ultragrips