G35cJ

We have just made a 3000 mile trip from DC to Florida in our new 09’ ML320 BlueTec. I bought the car in late September last year and decided to take it on the family trip to Florida this holiday season. The car had about 3000 miles before the trip, so it’s broken in. The oil level was a bit low by then and looked very dirty. I topped it off by adding half a qt of oil, but the dirtiness of the oil still bothers me, especially the factory recommended oil change is still 4000 miles away. I checked the tire pressure first time since delivery and found both rear were low at ~33psi. Factory spec for tire pressures are 32psi front and 38psi rear.
Before the trip, the mpg was hovering around 23~24mpg for combined city/highway driving. I was hoping for some big improvement in this trip, which I got indeed. I have not calculated the mpg for the entire trip, only data from the dashboard reading from different sections of the trip. The first part from DC to Jacksonville (~800 miles) I averaged 27.1mpg with two adults and two kids on board, all highway mostly cruising 75 to 90mph. The best gas mileage I got from this car was a 28.9mpg, a round trip from Homestead to Key West (~260 miles) on route 1. This was surprising, since we had lots of traffic jams along the way, and took us 6~7hrs driving time for the trip. But when moving, the speed was around 60~65mph, so that’s probably the reason.
The car felt very stable on highway at reasonable speed. The driver’s lumber support is superbly comfortable for the long trip. I am not sure about the back seat, but my kids had not complained about it. We drove though pouring rain for long stretch of roads in South Carolina and Georgia, and the ML always felt secure and sure footed. Highway acceleration was satisfactory, I never felt under powered, but the thing did feel out of steam above 90mph.
Now some cons about the car. The A/C ventilation system is wired. In many different settings, one would be too cold, but one click up would be too warm. This is not limited to one particular temperature, I have no idea why. Also, the rear vent is a joke. The air pass through it was so weak. I am wondering if it’s working right. Also, the right side mirror is partially blocked by the window frame; maybe they can mount it further back a little.
Just before our trip, we had 2 feet of snow here in DC and the ML drove through it without any difficulties, just in the cold weather, the fuel economy seemed decreased a bit.
So overall, I am satisfied with my ML and looking forward to more road trips in the future.

C-rod

somewhere, that their is a software upgrade to allow more air through the rear vents..l know it sounds crazy !!!!! l will try to find it and post it....

C-rod

still doesn't make sense !!!!!!!!!!!

http://www.benzworld.org/forums/w164...ir-center.html

gsrjc

I believe that if the rear vents are on, you actually have to have one of the three vent buttons pressed (the ones that allow air to go up, straight at you, or down). If none of these are pressed, I don't think air goes through the rear vents. I'm just as confused.

Cal

Excellent report! Amazing what the real world gas mileage on the Bluetecs is. They really underestimated the published EPA gas mileage for these cars.

boiler1991

With just over 5000 mi on the clock, I've taken 3 or 4 short road trips. Two weeks ago from Louisville to Nashville averaged about 27mpg. Best was round trip to/from Milwaukee - 29mpg! Consistently seeing 20-21 around town.

scootr29

It is the nature of a diesel to get the oil "dirty". This is the reason oils for diesel vs gas are not interchangeable. Soot is a by product of diesel engines and the diesel oil is designed to accept and work with this soot. Soot is black so the oil turns black almost immediately.

It is very important that you make sure the correct oil is used when you do the first oil change. If you take your ML320 to the Mercedes dealer just double check with them and make sure the correct oil is used. If you do your own oil changes again make sure you purchase the correct oil. It is imperative that the oil you use has 229.51 on the bottle.

I currently use Mobil 1 ESP 5w30 or 5w40. I have attached a list of all oils that are 229.51 certified.

http://bevo.mercedes-benz.com/bevoli...898641a88c6693

dgiturbo

Ditto on the oil type. I have 65K miles on mine, and used the Mobil1 ESP from day one. I also change it every 5K miles. I know Mercedes claims 10K+ on the oil change interval, but I intend to keep this truck for a very long time, and would like the turbocharger to have a fresh supply of oil at all times. Do double check with the dealer so they are no errors. It will destroy the DPF if even a small quantity is used.

As for the mileage in winter, gas stations switch over to "Winter Blend" which has some additives (possibly kerosene) to prevent fuel gelling. This blend causes a marked drop in mileage. (Probably why your Key West MPG was so good, as I doubt S. Fla uses winter mix.)
Above 50 degrees, I usually average 27-31 MPG on the highway, but once they winter fuel hits, it drops to 21-25. If temps where you live drop below say 20F, I would recommend a fuel additive. I use Power Service and have had no issues at -15F. (Previously without the additive, the truck did not start at the same temp.)

As for the side mirrors, you will have to get used to looking over your shoulder. Sorry. It is a bad design. And have no fear when you have to go through deep snow. What this thing can do is unreal!! I have towed a loaded utility trailer through an unploughed alley with snow about as high as the front grill, and the truck could not care less. Punched right through and kept going. I made a posting about it with pics, do a forum search.

Check your mileage again after 15K miles on the engine. You will like what you see!! Enjoy the truck.

azcarguy

[QUOTE=G35cJ;3880789]I checked the tire pressure first time since delivery and found both rear were low at ~33psi. Factory spec for tire pressures are 32psi front and 38psi rear.


I assume you're talking about the rear tire pressure as the "loaded" number at 38 psi? If I read it correctly on my fuel door the "normal" pressure is 32 front and 32 rear.