75ZT Community

I went to check my tyre pressures the other day. One because I hadn't done it in a few weeks and two because they did feel a bit off.

To cut a long story short I had a run out to Nottingham from Lincoln today and just by making sure the tyre pressures were correct I got 44 mpg rather than the 39 I got the week or so earlier for the same journey!

I honestly didn't think it would make 10-12% difference to the fuel economy the tyre being down by a few psi each!

Clifford.

You have just proved the point. Accurate (or near enough) tyre pressures make a helluva difference, to handling, ride quality, fuel economy and tyres longevity.

Not sure what you put in but I put in 2.5 bar in the front and 2.4 in the rear. I know it might seen a little high, but I found i the best for all round economy/handling/ride.

And just a note, it doesn't matter what size tyres you have on the car, the recommended pressures remain the same because it is the pressure in the tyre, not the amount. A lot of people think that because they put on bigger tyres it needs more pressure, false. It might need more air, but the pressure reading is common.

Ciao.

I just did mine as per the service manual, so for my engine & wheel size it was 36 psi (2.5 bar) front 32 psi (2.2 bar) rear.

Yeah it's funny how people tend to ignore the meaning of the units.

Well there's me having ran with the wrong PSI since 2009 - 32psi all round! :-S

Check your own user manual for your car, there are variations. Mine reads 32 all round and that's what I use.

Hi, just thought I would post this link for those of you who have no Owner's Manual: http://storm.oldcarmanualproject.com/ro ... manual.pdf

Cheers.

Useful link, though it does disprove what you said about pressures staying the same in spite of tyre size. Look at the diesel: 32/30 on 195 65 15, 30/28 on 205 65 15.

The pressures are set to give a particular sidewall height. Not enough height and it will flex too much and the sidewall will overheat. The pressures will be similar for sure, but not always the same.

RhodieBill wrote:Hi, just thought I would post this link for those of you who have no Owner's Manual: http://storm.oldcarmanualproject.com/ro ... manual.pdf

Cheers.

The chart in the facelift manual is different, or rather has different tyre sizes to reflect what was fitted from the factory.

After Jake said his was 32 all round I had to go check again lol! For mine CDTi Auto on 215/50 17 tyres it's definitely 36 front, 32 back. Seeing as you've got apexes on yours now Jake 32 all round is right according to the manual.

Clifford.

As its Winter thought I would bring this back to life as Tyre Pressures are important.

I have just fitted my Winter Tyres, does anyone else change each year? You must by law in Germany and many foreign Countries. The difference though is surprising holds and drives better on snow/ice than a 4x4 on Summer (normal) tyres, once 8C or below they always perform better than Summer tyres in UK.

Don't also forget Pressures are different for Auto/manual gearboxes and Tourer/saloon models Rover/MG models.
The latest book supplied with my car, 215/55/R16 W XL, MK2 CDTi Auto (Year 2005) has for my car: Normal: 34F 34R over 100mph 38F 36R Towing: 34F 36R.
Normal is with 80% fuel up to maximum GVW*. *(Gross vehicle weight).

As previously stated, I put 36psi Front and 35psi Rear. But then I have driven a couple of miles to get to the garage, so my 'Cold' pressures would be slightly lower. (Tyres 215/55x16 Conti Pro-Contact2).