300e owners what brand of oil do you use?
 

I was just wondering what brand of oil do you use for your high mileage m103 engine? I use valvoline max life.

I use Mobil Delvac 1 (5w 40). Very inexpensive and it holds a steady viscosity very well.

http://www.mbendi.co.za/mobilsa/prodserv/datasheets/auto/auto01.stm

I don't know what you consider high mileage, and I don't feel that oil choice is related to a particular engine type except for, in some cases, whether it is gas or diesel.

pmizell is using the absolute ultimate oil IMHO. The universal grades have more detergents and although specifically designed for diesels, are fabulous for gas engines as well. Of the universal grades, Mobil Delvac One is THE BEST!

I also use universal grade, but a less expensive one, Chevron Delo 400 Multigrade. This is 15W40. I had a head corrosion problem at about 173,000 miles. When I took it apart, the cylinder walls had no ridge and showed very prominent crosshatch.

The car now has 237,000 miles and uses no oil.

I personally believe that these oils that are supposed to be for high mileage engines are a bunch of bunk. It is possible that in a worn engine, there is an advantage of some sort, but they propose using this stuff at 70,000 miles. In todays engines, with fuel injection and modern oils, if properly maintained they are not even broken in at 70,000 miles. I believe that applies to almost any make engine sold today that has fuel injection.

Good luck,

Brands of Oil
 

On the subject of oil (again). Is there a brand that is better suited for keeping the engine internals clean. I just purchased a '92 300e and looking inside the valve cover there is a black buildup on the cam and rockers. The car has 105,000 miles and was very well maintained. My old '88 260e with 142,000 miles and it is so clean inside you could eat off it. I'm trying to figure out why the one engine is so dirty. I came up with two possibilities:

1. The 300e might need valve stem seals. Combustion gases are getting into the valve cover.

2. The previous owner used a brand of oil that didn't have sufficient detergents to keep the engine clean.

Anyone else have any experience with this concern?

John,

You need to add one more distinct possibility to your list; it wasn't changed often enough. Most all modern oils will keep an engine clean if they're changed often enough. If a car is driven very short hops with no chance to warm up, then 3,000 mile intervals aren't even adequate.

The best way to now get it cleaned out would be to use a universal grade oil, such as Delo, Rotella, Delvac or any other that is designed for diesels. These oils have more detergents. If you would drain the oil while the oil is at operating temperature, which is typically about 17 miles of driving, and let it drain for a while, preferably overnight, then put in your universal grade. Do this about every 1,000 miles for two or three oil changes, I'll bet you can then pull the valve cover and find things crystal clear.

Good luck,

Thanks Larry, I'll definitely try that. I just ordered some new valve stem seals too. It seems the car is using quite a bit of oil and based on what I see in the valve cover, there is a good possibility that the seals are crispy.

Right on with not changing it often enough! THat is one major cause of head gasket repair on the M103 every 150Kmi or so. Be prepared! You might want to wait or do it all right now. Sooner or later, its very likely to need a head job.

-brian

Brian,

I respectfully do not hold with such claim regarding the M103 head gasket. I certainly do not believe the head gasket should be changed because of a certain mileage achieved.

The M104 is known for excessive frequency of headgasket replacement necessity. But even those engines do not ALL require this repair. It is easy to get the idea that all engines of a certain model that frequently have a certain failure will require the repair. This is not true. The service people see many failures of a certain model, but that means the failure right is something like 15% which would be a high failure rate, it does not mean that you are guaranteed to experience such a problem. 85% chance of NOT experiencing such failure is not real bad odds.

Merry Christmas,

I use Havoline 10/40 '90 - 300E - 2.6 - 119,600 miles

I use Shell Rotella dino, and now the Synthetic version. I firmly believe it has cleaned my innards (all my cars are used and 3 did not look so good inside the oil filler hole when I bought them).

Larry,

My mechanics usually tell me they ALL need a head job eventually, M104 is usually between 50-75Kmi, M103 is usually around 150Kmi. Of all the cars they service with this engine, I'm pretty certain they'd say every one has had or shows signs of needing the work. They do a lot of cars that they don't regularly service because they have a very good reputation. It comes in spurts, but I've seen them do 2-3 a week from time to time (M103 and M104 combined).

Merry Christmas :)

Regarding the M103 motor, consider what Steve Brotherton had to say in this thread:

http://www.peachparts.com/shopforum/tech-help/28450-average-price-valve-job.html?highlight=seals

Some might go beyond 150,000 miles before a COMPLETE valve job is required. I think alot of it has to do with maintenance, quality of fuel, driving habits and how often the engine got REALLY hot.

My 2 cents

Well, every motor will need head work eventually.

That fact has nothing to do with head GASKET failure.
The top cause of premature head gasket failure is overheating, not oil brand or lubrication.

Oil and engine wear
 

In my experience, as long as the oil and filter are changed every 3000 miles or three months, I have seen no real difference from one oil to the other. As has been mentioned throughout this post, frequency, I think, is the key.

My 103 has 127000 miles and is rapping at start up and consuming a lot of oil (1 quart every 400-500 miles).

I am planning a head job in the spring. I'll pull the head and send out for machining and valve job. Based on all the threads I've read, valve seals are probable culprit. Will do valve job to be sure.

As a side note, I think it's a little odd that this type of work (vavle job) is accepted as "routine maintenance" on these cars. My expectations prior to buying this, my first Mercedes, were that a Mercedes was bullet proof and long lasting. My car has definately not lived up to my expectations.

Have a great Holiday,
Joel

I run Mobil Delvac-1 in ALL my vehicles. some are nearing 300,000 miles with no oil consumption.