ML 500 Oil Change
 

Just finished my first oil change on my 2003 ML 500. In order to get to the drain plug I had to remove a large plastic cover under the oil pan. I had to break all the plastic screws in order to remove this cover. My (question) is this plastic cover necessary ??? Is it OK to leave it off ???

After asking myself the same question a few years ago, I looked under some of the newer ML loaners I drove while having mine worked on at the dealer. They didn't have one so I figured I'd leave it off. One less thing to mess with when I do my oil changes. ;)

That plactic cover serves 2 purposes.

Keeps SOME un-wanted things from the engine area.

ON the highway it provides some "areo-dynamics" & allows for better fuel mileage.

Also gives the false impression that MBs don't leak oil.:D

OK Guys thanks for your help. If I can find some more of the plastic screws (with out going to the dealer) I'll put it back on. If not it will stay off.

Oil Change
 

I use cable ties as they are cheap and easy to use

take the easy way out and use a suction device to remove the oil. MUCH easier and no chance of stripping out the drain plug...........

I disagree. Whenever possible, you should pull the plug and drain the oil that way. MB (and most vehicle manufacturers) put it there for a reason: Sludge collects on the very bottom of the pan, as does other various matter, such as metal shavings. While suctioning can get most of the stuff out, it leaves that very bottom layer of gunk on the pan, and does not clean off the "stuff" on the end of the drainplug (for those who do not know, most oil drain plugs are actually magnetized to attaract metal particles).

The trick when pulling the plug is when you reinstall it, do not torque it within an inch of its life, as many amatures do, as they are afraid it will fall out. If you properly torque it, it should last a long time, as will the seal on it (if so equiped).

AT dealer we always suck-out the oil.. The suction machine gets way more oil than draining as the plug INS'T on the bottom and the dipstick tube DOES go all the way to the bottom..

MB recommends suction & has for decades...that is the reason that all of the filters are at the TOP of the engine.

Last car not to have filter at the top was the R107 (SL's)

The oil plug on the M113 engine (G500) is not magnetic. Nor was the drain plug on the M110. I would guess that the M112 is not either, but that's just speculation based on the fact that the M113 and M112 are clones of each other and share many of the same parts.

A good vacuum removal of the hot oil through the dip stick tube is just as effective as a bottom drain, and a heckuva lot less messy.

DCF

If you wish to continue to drain the oil, I would recommend that you replace the crush washer under the bolt with every change. It is designed to seal the mating surfaces of the pan and plug. They used to be included with the filter but now I believe you have to purchase them seperately.

I used to drain the oil the conventional way, but then I realized suction is the better way to go. The drain method shoots oil onto rubber suspension parts (not good) and I never could figure out why the drain was on the side of the pan, as opposed to on the bottom. Protection, I suppose. Anyway with the plug located a 1/4 inch up the side, draining doesn't remove all the oil anyway.

The most important rules to adhere to are :

Always run the engine for a few minutes to warm up the oil and keep the contaminants in suspension.

Use a quality 0W40 synthetic motor oil, such as Mobil One.

Use one of the new "fleece" type filters and replace all four O-rings on the housing.

DO NOT OVERFILL.......The range on the ML dipstick encompasses approx two quarts. I purposely leave my ML about 1/2 quart shy of totally full, so that I can get a more accurate reading on the dipstick.

Once you purchase and use one of the suction devices, you will be a believer. Much easier to recycle also, since you have a reservoir you can pour out of instead of a huge pan. My 99 ML430 is approaching 250,000 miles and I attribute this remarkable mileage primarily to synthetic oil changes every 10,000 miles since day one.

No question, but get one like this:

http://www.thetoolwarehouse.net/shop/MIT-7201.html

If you get a "Topsider" brand, it'll frustrate you enough (the suction tube collapses under vacuum and slows the removal down to a trickle; and it's not big enough to hold a crankcase full.) that the underneath messy way becomes much more inviting.

I guess old habits die hard, as I prefer letting the car sit, letting everything settle to the bottom, then pulling the plug and letting the crud out (I have no problem getting a little messy). However, I do agree that the positioning of the plug could be better. I also agree with the comments regarding the fleece filters, they are a great step ahead of the basic paper ones.

Playing devil's advocate (as I am prone to do here). If the "suction" method is so great, and MB endorses it, why even have a drain plug? MB obviously put it there for a reason, as they have no problem doing other crazy things on their vehicles that require special tools, so why not just force folks to do suction by deleting the plug? After all, I am sure we are all in the minority of MB owners, as the majority of US owners would never even think of working on their own car, especially those who generaly buy Benzes. So if most are going to the shop anyways, why not make it suction only?

DCF

Good question. As radbob in the first post mentioned, you have to remove a panel to even get to the oilpan. I had a 86 Porsche 944 Turbo that had a similar arrangement. A huge panel that had to be removed first. All in the name of aerodynamics. It was a very clean design but not very user friendly for the do-it-yourselfer. Heck, on the Porsche Boxter you can't even SEE the engine, all work is done from underneath.

DUTCH

That is a great price on the MIghty-vac. Mine is made by Tempo, very similar but I think the Might-vac is a little more versatile. I first got interested in the suction method of oil-changing with a boat I used to have. Impossible to even get to the drain plug on an inboard, so suction is the only way to go !!

I prefer to drain from the bottom using one of these http://www.fumotovalve.com/ with a nipple on it with an 8 inch 1/4 inch dia rubber hose attached. Does a nice clean job for me. My 2 cents. ;)