What Tyre Pressures

[SLinKyjoe]

you can experiment a bit with your tyre pressures. I would have thought you should have nearer 32 in the front and 34-35 in the back by the sound if it. but if you add 3-4psi, you will not be over inlfating the tyre, but you will stiffen the tyre wall a bit, this adds an element to your road holding and loses and element of comfort. best not to go below the tyre pressure recommended, and never exceed the maxmum tyre pressure stated on the tyre.

i tend to run mine 3psi above normal to increase the road holding.

your car will naturally increase its pressures by more than 3psi when driving on a motorway anyway so it wont make them wear out wrong. in theory it will reduce the rolling resistance a small amount so you benefit from better MPG. but its tiny. to see a difference you need to inflate them to almost the maximum, and then you would need to allow them chance to cool when on motorways at regular intervals, and you would be best to avoid any long high speed runs if you do that.

 

[hawk20]

I did 30psi all round on my C class.
Then did 30psi all round on my E class.
Now do 30psi all round on my S class.
I think these figures fit what it says on the tin for when you are only two people up (as I usually am).
In theory I put extra pressure in the back wheels if I do a longish run with four people and lots of luggage. But then I hardly ever do a longish run with four people and lots of luggage. So 30 psi all round it is then - so easy to remember.

Last week was at my local Merc dealer when the foreman noted one of my tyres (passenger side rear) looked a bit flat. I was surprised as only two weeks old. Turned out a screw had gone into the tread. Pressure only 10psi. Ouch! I try to remember to check weekly, or monthly at the latest, as tyre-place notices often say to do. But slow punctures can happen any time and could be a killer or could ruin the tyre if the drop in pressure goes unnoticed (not good at £1000 for four of them). Makes we wish I had tyre pressure monitoring. Anyone got it? Is it any good??? Presumably it is not a retro-fit item?

 

[SLinKyjoe]

. So 30 psi all round it is then - so easy to remember.

I just helped out one of our Stewardessess, whose Golf had a going down tyre. or it looked like it to me. so i checked them. 8 psi and 14psi in the other rear, and 23 in both fronts. Got the compressor out and filled them up and insisted she did something about it. I put hers to 30psi for the same reason you use it. she has had 4 valves changed and the tyres inspected, rebalanced and put back on and the front to back swap ready for winter. £20 all in. Wish I was blonde!

one yesterday was 25, all others 29. topped it up to 31. today its 30. will check again next week, when her car is in our car park again. i may try to look for a screw head or something.

.
Last week was at my local Merc dealer when the foreman noted one of my tyres (passenger side rear) looked a bit flat. I was surprised as only two weeks old. Turned out a screw had gone into the tread. Pressure only 10psi. Ouch! I try to remember to check weekly, or monthly at the latest, as tyre-place notices often say to do. But slow punctures can happen any time and could be a killer or could ruin the tyre if the drop in pressure goes unnoticed (not good at £1000 for four of them). Makes we wish I had tyre pressure monitoring. Anyone got it? Is it any good??? Presumably it is not a retro-fit item?

Its a pity we learn like this. you go years checking every week and never a problem. then you check once a fortnight, then once a month, then when you can be bothered and hey presto, 10psi and a screw.
I do check them before i go on any long run that involves motorways, altho quite why i check them just before i set off i dont know. i should have a look the day before so as i can get any problems sorted before i make the trip, as opposed to cancelliing it. I, boringly, check the fluid levels inclduing washer, and the lights too.

its good practice.

The chrysler has tyre pressure monitors, and it seems accurate altho its in bar and not psi. Strange considering its supposedly yank! it registers too, as i let the air out and filled them with Nitrogen last week. one has a slow valve, so it took ages to let out and inflate again.

 

[SLinKyjoe]

D'oh......Posted the darn thread now and it wont let me delete it..

quick bit of merging and both thread now together in same place in case anyone reads it all and wonders what happened.

and just to cheer you up. the new chrysler has on the front 245-45-20 ZR's and the rear 255-45-20 zr's
Help yourself to check out on www.mytyres.co.uk just how cheap ther are and just how many options are avaliable!!!

no wonder I am still up at 3am

 

[Myros]

Joe, I just knew you had to get nitrogen

in there somehow. Have tank, will pressurize? Next time I'm at the airport, I'll pop by and get mine done if you don't mind. I was blonde when younger, but am a bit more mousey and grey now.

 

[television]

Makes we wish I had tyre pressure monitoring. Anyone got it? Is it any good??? Presumably it is not a retro-fit item?

Yes,I have it too, When I tried my spare wheels,it soon told me,"Check tyres" "check tyres" I think it is a retro fit as I have read it somewhere.

Malcolm

 

[Rory]

Makes we wish I had tyre pressure monitoring. Anyone got it? Is it any good??? Presumably it is not a retro-fit item?

Passive tyre pressure monitoring can be enabled on the latest C Class if a friendly technician knows the correct proceedure in StarDiagnose - this ties in with the cars existing ESP system and compares the rolling circumferences of the tyres.

Full tyre pressure monitoring could be retro-fitted but it looks big job.

Whether these things can be carried out on S Class, I don't know.

 

[SLinKyjoe]

in there somehow. Have tank, will pressurize? Next time I'm at the airport, I'll pop by and get mine done if you don't mind. I was blonde when younger, but am a bit more mousey and grey now.

Its at my home. feel free to call round. its free.

 

[daveenty]

@SLinKyjoe

Any benefits with Nitrogen?

I can understand it on aircraft for obvious reasons (spent too much time in Toulouse)....

Only thing I can think of with a car is the pressure stays constant throughout the temp-range?

 

[SLinKyjoe]

Any benefits with Nitrogen?

none unless you are racing. I just have a cylinder which needs using up.

it does hold the pressure more constant as its not affected by humidity, and this is also the same when driving, but for road use, its more important to keep your tyres in good condition and check the pressures regularly.

even in racing its a tiny differential, but they measure it in 0.1psi's unlike us, so they can see the difference more. to be fair, its more use to them in high humidity conditions where the moisture in air can affect the pressure more.

they also use it in air operated tools, as its less of a risk with oils and stuff knocking about, so there is the economy perspective too for race teams.

anyhow. makes no difference in road car use.