VW Golf GT Sport (140 BHP) - 91W and 91Y Tyre Pressures

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Mon 28 May 2012 23:59
VW Golf GT Sport (140 BHP) - 91W and 91Y Tyre Pressures - Tony1DB

Hello all and Honest John!

I hope you can help me!

Basically, my question is whether 91W rated tyres and 91Y rated tyres (NON-XL) should have different tyre pressures?

I have a VW Golf 2ltr diesel (GT Sport 140 BHP) which has 225x45x17 tyres - normally 91W rated, I believe.

About 3000 miles ago, I changed all 4 tyres to 225x45x17 91Y rated Goodyear Eagle F1 Asymmetric 2 tyres (non-XL), which are excellent by the way.

I have noticed that my fuel consumption has dropped by between 5% and 10%.

The info. on the filler cap, says I should inflate my size tyres to 2.3 BAR (about 33.5 PSI). The AA website claims these size tyres (no mention of the rating) should be 35 PSI front and 32 PSI rear - though I have been following what the Manufacturer says (no offence AA!).

This does not bother me as I would happily sacrifice some fuel consumption for safety, but now I am thinking that maybe my new 91Y rated tyres are not correctly inflated.

I know that the GYEF1's are excellent tyres with very good grip, so maybe the drop in fuel consumption is due to them being slightly more 'stickier'/grippier than my old tyres (which were worn, so maybe that is a factor?), but I keep reading reports saying that these GYs also have low rolling resistance?

Soooo, my questions are whether 33.5 PSI is too low for 91Y tyres and, if so, what should they be inflated to, or whether tyre pressures for W or Y are the same?

I do not want to over-inflate the tyres at the risk of safety but I also do not want to under-inflate them and wear them out too soon!

HELP!

Thank you very much and I look forward to hearing from you...

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Wed 30 May 2012 21:28
VW Golf GT Sport (140 BHP) - 91W and 91Y Tyre Pressures - Mike H

There's no right or wrong answer. The manufacturer simply bases their recommendations on what works - i.e. they try different pressures and go from there. I can say that, on my Saab (see your other thread re winter tyres) with the same size tyres, Saab recommend 36psi front & 35 PSI rear. I use 94 (XL) rated tyres BTW. I ran the F1 asymmetrics by coincidence at a higher pressure, normally around 38 front and rear, and they wore out in the way that you'd expect from over-inflated tyres, with less tread in the centre. Didn't make any difference to fuel consumption, perhaps it drove a little more sharply which was the plan, but lesson learnt there - use the manufacturers recommendation! And the wear rates are rubbish, I got around 12,000 miles from the fronts, never seen lower than 20,000 with any other tyres. But they did grip well!

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Sat 9 Jun 2012 14:54
VW Golf GT Sport (140 BHP) - 91W and 91Y Tyre Pressures - Tony1DB
Many thanks Mike (and sorry for the delay in replying!).
I will follow your lesson and just stick with what the manufacturer says...
Not sure if you had the F1 Asymmetrics (1) or the F1 Asymmetric 2's. I have heard that the 1's did wear out quickly but that GY had improved the wear rate with the 2's - well, I hope they have!
I bought the 2's knowing that wear might be an issue, but I was after the grip, which, to me, is more important than wringing every last mile out of a tyre.
My 2's have only been on for about 2000 miles, so I'll wait until I've done at least 5k and I will report back with wear rate.
Thanks again for your reply!
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