superangrypenguin

Ever wonder what tire pressure you should set your W204 at?

I entered into a lengthy discussion with MB corporate once I figured out that the tire pressure that is to be set for the various W204s is dependent on year of make.

I found this to be really odd given the fact that the suspension geometry didn't change (as evident by the alignment printouts that indicated the ranges of what is considered 'green' is the same for cars made since 2008 for the W204 body).

After pushing their engineers on this, I was told that the tire pressures slowly increased over the years in order to help MB stay 'green' on fuel efficiency. Therefore, MB jacked up the tire pressures year over year in order to try and boost fuel economy.

Therefore, if you're like me and you don't really care for 1MPG here or there and you want a more comfortable ride, feel free to set the tire pressures as low as 28 front and 33 rear.

I've attached a PDF from MB corporate which lists front/rear tire pressure for each body shape (some of these are referencing coupes - and some are sedans). However, as I can tell, in the 2008 body shape, 28 front and 33 rear was listed as OEM spec for the staggered 17" setup. - so now I've set it to such on my vehicle and it's MUCH more comfortable.

**warning: If you live in a place that has wildly different cold/hot temps in a given day, make sure you set your PSI when it's coldest out otherwise you run the risk of being underinflated on a cold day if you set your tire pressure on a hot day**

Hope that helps!

Carsy

Good thinking for a more compliant ride but if you drive on potholed road, a higher pressure will protect your rims from damage.

C300CA

I used to set couple psi higher than the sticker psi, ie, 30 on front 35 on rear. I do that not because of slightly higher mpg benefit, but because of air slowly leaking. When I went in for service, dealer always bled them down to standard 28/33.

Last time B service, dealer set front and rear both to 36. I found it and bled them down to 30/35. I posted in another thread that this dealer screwed up the brake fluid service but they fixed it and gave me free 2016 map update DVDs upon my request.

superangrypenguin

Great feedback - and duly noted. I've been riding on the 28/33 setup for a while now, which for 90% of my driving actually means it's closer to 30/35 because it's usually 15 or so degree Celsius warmer than the coldest temperature at night which I where I set my 28/33 setup.

I can't say I've run into any issues at all. I used to set whatever was on the door filler cap (33/38 IIRC?) which probably meant 35/40 on a hot day, and so this drop of quite a bit of PSI hasn't affected my fuel efficiency or caused damage to my rims. However, the ride is MUCH more to my liking

//old man rant over