I just recently bought a 2003 ML 350 for my wife. Sold her 1997 Cadillac SLS (most expensive car to maintain besides ENZO Ferrari). Did some minor routinemaintenance to it and the 350 is running strong. At its heavy weight, I still can't believe how hard it pulls away from the line. Anyway, love everything about it except for the hellacious gas mileage. Knew about it ahead of purchase. My idea to help with this problem is a drop-in K & N air filter. I have used these in other cars and have had good results. I will post some results when I get some good comparison data between the stock filter mileage and the K & N mileage. Please reply if anyone else out there has already tried this. Would like to hear your results.

 

Hi,

I can confirm that using a K&N air filter will improve your gas mileadge of at least 30%.
I have noticed maybe a 40% increase on my ML 320, whithout talking of a better acceleration.

I did have to spend some time and find a way to fix the new filter in order not to lose it while running on bumpy roads or just beacuse of vibrations. sothis is my only suggestion, change without worries the filter, but make sure it is well fitted and that you will not lose it during your ride.

Francesco

 

I appreciate the input but I don't understand what you mean by lose the filter. Mine is a direct replacement for the oem application. Fits perfect! 30% sounds like a lot of gain also. What is your MPG reading. So far, my first reading has only been in town driving, and I let the 350 have it. I hammered the gas at every stop light for 4 days. I drove it like a screaming F1 machine and got 15 mpg. I am waiting to see the results from some "Grandpaw Driving". Have not had a chance to drive it on a long highway trip yet. Maybe soon.

 

Yes, you are right... I have fitted a K&N Induction kit which does not resemble the original one, hence the need to fix it properly. I wasn't thinking you meant the K&N replacement to the original.

the one you mean is definitely easier to fit and cheaper on the long run (as the induction one as well) but in this case I would not know about the performance change in mpg anf acceleration.

My ML has a V6 3.2 engine and I get 14mpg now. It was much worse on gas before. Sorry if I confused you with my answer.

 

Update- My wife is consistantly getting around 16-17 mpg in town. Much happier than the initial 11-13 mpg readings. Still have not been able to go on highway trip and gas is now $4.00 a gallon. Maybe it will recede sometime soon and I can give some data.