"Eco" tyre pressures?

[languageservicesco]

We have recently bought a CLS 500 with 19" AMG rims. It arrived (from a non-specialist car dealer) with 2.4 bar on the front and 2.7 on the rear (according to the tyre pressure monitor), which doesn't correspond to anything . I know the recommended tyre pressures are in the filler flap, but we have a Volvo XC90 and Volvo also recommend an "eco" pressure (38 psi all round) that is meant to be fuel-saving but still a good pressure. Does MB have anything similar? If not, do people generally keep to the pressures on the filler cap or have them a bit higher?

Any input much appreciated.

Kevin

 

[L John]

Thanks, I just spat coffee on my keyboard, ECO pressure on a CLS500, nice one.

There is a jokes thread somewhere on the forum to post great stuff like that though

 

[languageservicesco]

Thanks, I just spat coffee on my keyboard, ECO pressure on a CLS500, nice one.

There is a jokes thread somewhere on the forum to post great stuff like that though

Yeh, yeh. A small percentage of a large amount is worth having if you ask me. The XC90 is hardly a money-saver.

 

[languageservicesco]

If I had said it was a CLS350 CDI with AMG wheels, would the answer have been different? I guess not. So, the flip side of this question is, I assume everybody simply follows the recommended pressures given on the fuel flap and they work fine?

Cheers,

Kevin

 

[toby1]

Fuel flap settings are fine. Put the kettle on and have a cuppa.

 

[geraldrobins]

I set my tyres to the recommended pressures as at 36psi seem high enough anyway. Im sure it wouldnt do much harm to run a bit higher so long as you monitor the wear. The ride might be a bit harder however if you have 19 inch rims its probably pretty hard already.

 

[Triv]

And there I was thinking that recommended tyre pressures are recommended for a reason.
You never know, if you pump them up enough, it might fly...

 

[Oarsman]

Beware of over inflating as you will just wear out the centre section of the tread.

 

[languageservicesco]

I set my tyres to the recommended pressures as at 36psi seem high enough anyway. Im sure it wouldnt do much harm to run a bit higher so long as you monitor the wear. The ride might be a bit harder however if you have 19 inch rims its probably pretty hard already.

Already 40 odd psi at the back, but air suspension is a wonderful thing. Looking forward to what it is like at the recommended 30 all round. Recommended pressures are always going to be a compromise, but there seems to be a general feeling that they are pretty good. Will sort them out in the morning.

 

[jberks]

As oarsman says, over inflating will wear out the centres, under inflation will wear out the edges.
Never heard of an Eco value. Sound a bit mad to me. The correct pressure is when a tyre wears evenly over the whole surface.
I guess volvos figures would be categorised as over inflation, in which case I imagine it would lower the rolling resistance and improve fuel consumption. However, any saving would be swamped with the premature cost of new tyres.
Plus grip must be compromised with less tyre in contact with the road.

 

[GEORGEROV]

Certain garages when storing second hand stock will over inflate tyres , not knowing how long they will have them sitting around . They wont take the trouble to keep them at recommended pressures .

 

[Ricardo_e220]

Not specifically heard of eco inflation, apart from people on fuel saving site will advise over inflating ( or putting them to the max level in the handbook)

You will find the rears in particular wear the centres out even set at the lower end of the pressure range... Overdoing this will as mentioned accelerate this, and make the car more likely to spin in poor conditions.

Unless you are doing a lot of miles ( doubt it with a 500) you really won't see any real benefit from this, but more benefit by driving smoothly and economically in mind ( if that's what you wish to do)

I drive my merc with economy in mind, as I do 35k miles pa in it... But my lotus I drive like I stole it.. I set its tyres to where I can use it best.

Enjoy the car that's what it's about!

 

[grober]

In recent years many manufacturers appear to be "ramping up " their recommended "standard" pressures to values higher than required for the load bearing characteristics of the tyre in question. [ the load bearing characteristics of a particular tyre increases with increased inflation pressure within its design pressure profile] Thus tyre wear and ride comfort become casualties in the CO2 emissions/ taxation wars. If you research it you may find you could safely run with slightly lower than the recommended pressures on the flller flap but I would not recommend it. However what is important in a front engined +rear wheel drive car is the relative front to back pressure ratios as this effects the tyres slip angle which in turn influences the way the car handles. In most cases the ratio is set up to yield a car with slight understeer on the limit as this is the most stable configuration for most drivers.

 

[rhud]

This is exactly right and can be seen with many MB BlueEfficiency models. The standard W169 A Class pressures are 29psi all round. On my Blue Efficiency model - same tyres, same suspension,but a little lighter due to weight-saving measures - they are specified as 32/28. All in the cause of claiming mpg/emission advantages over the competition.

In recent years many manufacturers appear to be "ramping up " their recommended "standard" pressures to values higher than required for the load bearing characteristics of the tyre in question. [ the load bearing characteristics of a particular tyre increases with increased inflation pressure within its design pressure profile] Thus tyre wear and ride comfort become casualties in the CO2 emissions/ taxation wars. If you research it you may find you could safely run with slightly lower than the recommended pressures on the flller flap but I would not recommend it. However what is important in a front engined +rear wheel drive car is the relative front to back pressure ratios as this effects the tyres slip angle which in turn influences the way the car handles. In most cases the ratio is set up to yield a car with slight understeer on the limit as this is the most stable configuration for most drivers.

 

[AGordCL]

I've found that most tyres sit between 30 and 34 psi, sometimes down to 28.

I quite often see people using the tyre pressure machine at Tesco and inputting the maximum psi for the tyres thinking that's what it should be!

I suppose they might think the tyre is now 'full up'...

 

[L John]

I quite often see people using the tyre pressure machine at Tesco and inputting the maximum psi for the tyres thinking that's what it should be!

I suppose they might think the tyre is now 'full up'...

Their airline used to be free, now they charge so too right I'll take all I can get in

 

[V6Matty]

Their airline used to be free, now they charge so too right I'll take all I can get in

ooo you from yorkshire :lol:

i have mine at 34psi all round, seems to keep everything wearing evenly and ride isn't compromised (that i notice).

 

[geraldrobins]

Interestingly I have Michelins as OE but looking at the Michelin website it recommends lower pressures for my car than MB do. Emissions maybe.

 

[languageservicesco]

Thanks for all the input. I have set them to the recommended pressures and have to say I haven't noticed any difference in the ride comfort, but I will leave them there. Taking it to Germany next weekend, so we will see if we notice any difference when the pressures are put up again, as well as seeing what it is like at speed!

 

[brandwooddixon]

You may not notice a difference in ride comfort, due to your airmatic suspension, but you will notice an improvement in wet weather stopping distances by running tyres at around 30psi rather than 45psi.