What Tyre Pressures

[Ian Brown]

Wear wise, I've just done a check and after 7,700 miles, I have around 6.5mm left (pessimistic measurement). Wear is even front to back which is odd, given that the front Bridgestones lasted twice as long as the rear bridgestones (and replacement contis), the first time round.

You must be about the only merc owner I know that there front tyres last longer than the front or you must have a very heavy right foot.

 

[jberks]

You must be about the only merc owner I know that there front tyres last longer than the front or you must have a very heavy right foot.

heavy - probably but not excessively so.

On my previous 2 mercs I rotated front to rear to get around the edges wearing too thin on the front and adjusted the pressures to keep the wear even across the width as time went on. In that way, I managed to get all 4 worn out at the same time. Then again, they were primarily town cars. It's only fairly recently that I've returned to the motorways.

However, I think my driving style does err towards the rear. Round town, I'm the same as everyone else I suspect, but on motorways I learned a while ago that if you simply keep a sensible distance, even in traffic (tricky but it can be done), you can use engine braking to the extent that I now consider any use of the brake pedal, whilst driving on a motorway, a failure. I found that in 80+% of cases, by backing off the throttle when someone 2-3 cars ahead starts to brake (guy in front is irrelevant as he's normally too close to the car in front and has to do whatever he's told by the brake lights in front of him), by the time you've used up the gap and are finally going for the pedal to lose that last 25mph, the car in front has already taken off again and you actually have no need to brake at all. This keeps front brake and tyre wear down, and best of all, reduces fuel consumption dramatically. Easily worth 5mpg.

You still need to accelerate again though, and with the bucket full of torque in the 270cdi, plus the occasional squirt of power to discourage that 'clever chap' passing up the inside in his BMW just because you can temporarily get more than a sheet of paper between me and the guy in front, the rear tyres can still take a bit of stick.

 

[television]

SL's like my V70R have a huge appetite for rubber, the V70 has been on federals (front) for I year, I have found them very good and quiete.

SL's don't do much more than 10k on the rears at over £200 for the Pirrelli roso's £100 for the federal's must be the way to go.

Malcolm

 

[OlafMaxwell]

I use Pirelli P6000 and find them best, compared with Michelin. Good all round. I have to run them at high pressure, about 38psi.

 

[OmniCognateNeutronRangler]

blimey that is high! I usually run around 28 to 30 psi on Contact ContiSport 2's. Do you not get odd tread wear at such high pressures, or am I running low?

 

[daveenty]

Got Conti's on mine and run them at 43 rear, 40 front.

Sort of in between makers recommendations for laden/speed & light/slow.

It works for me and wear is very even.

My rears also wear quicker than the fronts, probably is my driving style

 

[OmniCognateNeutronRangler]

maybe I have it wrong. Perhaps that's why I don't get this pulling to the left thing. Sounds like I should start a new thread on what tyre pressures "should" be.

Were did you see the recommendations? Are they in the hand book?

 

[daveenty]

Were did you see the recommendations? Are they in the hand book?

Usually under the fuel filler cap

 

[OmniCognateNeutronRangler]

Based on some comments on other threads I either have very low tyre pressures or others have very high pressures. I'm sure there are plenty of people on this forum that can point me (and I'm sure others) in the right direction to determine what tryre pressures we should be running.

I have 225x50x16 ContiSports front and rear on a 2003 C240 Avantgarde and I'm running them around 30 psi front and rear but it sounds from others that this may be a tad low.

Suggestions?

 

[OmniCognateNeutronRangler]

Ignore This, It Was Just Pointed Out To Me That I'm A Bit Of A Berk (although In A Much Nicer Way) And That The Tyre Pressures Are Shown On A Sticker Inside The Filler Cap. Live And Learn....

 

[OmniCognateNeutronRangler]

D'oh......Posted the darn thread now and it wont let me delete it. You are right of course. Mind you mine says 30 front and 33 rear when not fully loaded and I tend to be in the car on my own most of the time so they're only a little under. I think I'll put some more puff in tonight. As you say, put them in the middle somewhere.

Thanks for that, only had the car since March! Can't believe I didn;t pay any attention to the label.

 

[daveenty]

Can't believe I didn;t pay any attention to the label.

It's just one of those things you see everytime you fuel up, but your sub-concious directs you away from it (as fuelling is why you've opened it anyway)

Incidentally, mine are high because of the profile & width (265x35x18 rears)

Can't remember the fronts and it's raining so I ain't going out to look

 

[OmniCognateNeutronRangler]

Incidentally, mine are high because of the profile & width (265x35x18 rears)

rubber bands on bike wheels

 

[daveenty]

Yeah, but standard fitting (and *reasonably* comfy)

 

[OmniCognateNeutronRangler]

not to mention look serious cool (sorry, are 40 year old blokes allowed to say cool?)

 

[daveenty]

(sorry, are 40 year old blokes allowed to say cool?)

Don't know about 40 year olds, not been there for a few years

 

[Rory]

blimey that is high! I usually run around 28 to 30 psi on Contact ContiSport 2's. Do you not get odd tread wear at such high pressures, or am I running low?

I run my C270 estate with 30 front and 33 rear (the normal recommendation from the fuel flap).
RWD drive cars tend to wear the centres of the rear tyres and overinflation does the the same. If you combine the two you ought to considerably reduce the tyre lifetime.

Only prob with running pressures on the low side is you've got to be careful if you suddenly load up the car - like taking a bunch of people & their luggage to the airport. If they tyres flex too much they'll overheat and could blow out. However my tyres have never been anything other than slightly warm, even after fast motorway runs.

 

[television]

Don't know about 40 year olds, not been there for a few years

Go back there again, its great with the knowlegde you have gained since.

Malcolm

 

[television]

Running on the high side makes the car more economical, sinse less friction.

Malcolm

 

[brianha0]

The tyre pressures that are shown on the inside of the filler cap will be for the standard wheels that originally came with the car. If these wheels and tyre were changed to a different size then a different pressure would be required.
Regards Brian