Hi All,

I just bought 1988, 300E with 150k miles. I would like to switch to Mobil 1. Is it potentially damaging to the motor? Will I get oil leak? I listened to a variety of argument for and against Synthetic Oil for older motors.

Any comments from the experts here?

Thank You,

__________________
1989 300E, 152k miles
1988 300E, 172k miles


"There is nothing more expensive than a cheap Mercedes-Benz" -unknown

yes, many people said that it will cause oil leaking on the engine.

I will suggest you using semi-synthetic oil first. I am highly recommend Lubro Moly 10W40 (already mixed MOS2).

I've taken 2 cars from that era(one slightly older) past 300K using dino oil.

In my opinion, running a 16 yr. old car on synthetic oil is a waste of money. Use a good brand of dino oil, a good filter and change hot/often as Larry Bible has suggested and you'll be fine.

__________________
Mike Murrell
1991 300-SEL - Model 126
M103 - SOHC
"Fräulein"

I started the 560 out on semi-synthetic at 166K miles with no leaks or problems. At 192K miles I made the jump to full synthetic Mobil 1 0W40. After 1K miles on the Mobil 1 I see no new leaks or accelerated usage, we'll see how things look after another 2K miles.

__________________
Mike Tangas
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72

'02 CLK320 Cabriolet - wifey's mid-life crisis

2012 VW Jetta Sportwagon TDI...at least its a diesel

Non illegitemae carborundum.

Do not use oil containing MOS2. (Molybdenum Sulfide)
Although molybdenum sulfide is a very good lubricant, it is a solid (powder) and never dilutes in a liquid (oil). Some of the small oil passages in your engine can get clogged with the stuff.
Having worked in the oil business for a major oil company for all of my adult life, testing, comparing, blending and developing lubricants for major engine manufacturer, I can tell you that a good brand of mineral oil is all an engine requires. There is nothing wrong with high-end (price) synthetic but for most normal application, you are wasting your hard-earned money. I must say the oil comanies have done an extremely good job at marketing their high prices synthetic oil on with they make a very high profit margin.
I sometime compare using synthetic oil in a engine to washing your car with chirurgical certified grade distilled water. It does the job, but at what price?
JackD

regarding using an oil with MOS2 in it.... the cam oiler spray holes on my 560SL are only about 1mm square, and I would hate for any glob of lubricating gook to get stuck and cut off the perfectly good 20w50 conventional oil that the engine was designed to run for 400k miles on.

mess with a good design by adding snake oil and your bound to regret it

Mobil1 Synthetic causing oil leaks is a myth due to issues they had when it was first introduced a long time ago. Since they have added what ever to the product to take care of seals. Still I really question the value of going to synthetic on a old car. I use synthetic in my Talon Turbo but probally not the recent MB 300E I bought with 125K on it. Some advantages one may experience by using it in an older car/MB is the oil staying clean longer, so you may be able to extend oil service. Note from my experience that depends on the car and I have no experience with that in a MB. The other would be if you lived in an extreme cold climate you could use Mobil 1 0W40 all year round and get easy cranking during -20F to -40F(C) below zero and protection during the summer.

Other wise it probally not worth the extra cost if you change the Dino on a regular basis.

ahh another oil thread, it's been awhile.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Synthetic snake oil

Lets get this thread moveing. Dino is better then synthetic because it won't cause leaks, and it's cheaper. You do not want to extend oil changes beyond 3k miles. Lets see how good of a troll I can be.

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1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

I love these oil treads as they are a good benchmark to find out which oil company has made the most remarkable marketing job.
Synthetic promote leaks: That was a marketing counter offensive used by oil companies not in the synthetic oil market years ago.
Synthetic are cleaner for a longer period of time/mileage: Bull****
You get the same amount of sooth, contaminant, acid, dirt, dust, sillica in synthetic as in mineral for the same distance/time.
Synthetic can allow extended drain intervals: Bull***, Ask any engine manufacturer to give you in writing the OK to extend oil change intervals and still maintain their full warranty.
Synthetic are more stable at higher temperature: True, but the temperature at which they become more stable than mineral oils is well passed the desintegration point of an engine.
These treads are fun
JackD

I wish I had synthetic in my engine this winter! Cold starts at about 5 degrees F a few times at the airport were a little nerve racking (slow cranking)

Also when very cold my power steering pump would groan like an old lady until warmed up a little. Why would it do that? Maybe time for a rebuilt pump?

Anyone else have a 'Groaning Power Steering Pump' in very cold weather? It works OK otherwise.

(Currently all apart for timing chain and rail job)

__________________
Gerry

59 Ranchero
83 928 Euro S
84 928 Euro S
87 300D Turbo-Frybrid "WVO, Tastes Great - Less Filling"
90 750 IL
91 560 SEL

Oh yea. Anything below 10*F and the steering groans until it has warmed just a tad. Once it has warmed up for about a minute it is as quiet as always.

10*F seems to be a magic number for the 560. I have a sticking starter solenoid that won't engage on first crank when the temp falls below 10*F, catches on the second try. I figure I will let this ride until things get warmer and I'll be in the mood to lay out on the ground under the car. Not planning on doing that until it thaws out a bit.

__________________
Mike Tangas
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72

'02 CLK320 Cabriolet - wifey's mid-life crisis

2012 VW Jetta Sportwagon TDI...at least its a diesel

Non illegitemae carborundum.

I've run synthetic in any car I've owned that didn't leak oil for some years. Never have had one spring leaks after the change.

If you do change from dino to synthetic, change the oil filter again after 500-1000 miles, all the varnish will dissolve and particulates will plug the filter.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Jackd and Jim and to all in question, I am sorry you do not believe in synthetic oils as being far superior to standard oil. The fact is that synthetic oils lubricate much better than standard oils and in that fact alone, you will have an extended life of the oil before changing because there is ultimately less wear on your engine. With this in mind, with less wear, the engine will last longer before having to be overhauled. I don't agree that synthetics being as pricey as they are should only be used for newer cars and that on older cars you are wasting your money. I have used Mobil 1 synthetic oils all my 17 years of driving I have had and I have even compared synthetic to standard and there IS NO comparison. I put synthetic oil in my 93 maxima that I bought new and the day that I was converted over to MB and I sold my maxima, it had over 160k on the clock and probably had another 200k left on the clock without ever having the engine overhauled or anything done to the engine itself. I like the Japanese cars and they will go a long time, but if I had been using standard oil, I would have never gotten 160k with nothing being done to the motor. I was so confident in that car when I sold it that I would have driven it across the country and would have never had a second thought about it and even received top dollar for it due to it's care. The car drove like it was brand new. As far as oil life, I would normally get 7k-8k out of the oil before it would need to be changed. I could tell you no sooner than it was time to change the oil just by the way it ran. I have never been able to do that with standard oil. Synthetic oil does remain up in the motor longer without dropping down more than standard oil. The prime example, I can let my 420sel sit for 3-4 hours and then check the oil. The oil will register lower and sometimes give you the impression you are low on oil. I can start the car up and drive it for about 30 minutes and come back in and check the oil. The level will be on the full mark. There IS NO "synthetic snake oil". If you don't believe syns are much better for your motor, then you just haven't used them enough to really know whether they are or not. I pay about $4.75 x8.5 quarts everytime I change the oil and you can do the math, that is expensive. But, I do know that my motor will still be running smoothly and strong when all of these "synthetic snake oiler's" motors are being rebuilt because they are worn out. I can't say whether or not syns on an older car with higher miles will cause a leak, but I can say that the syns do have a certain amount of detergents in them that will help clean the gunk that may have built up over the years. I have changed to Mobil 1 synthetic on my 90 420sel that had 100k on it at the time and also on my 89 300se that had 175k on it at the time and never started a leak. Now, I will not vouch for anything other than Mobil 1 due to the fact I have no experience with the others, but if you want good oil, go with Mobil 1 syn and you won't regret it. I didn't mean to attack anyone really in my response, but I did want to share some education to anyone that might read these postings or is curious as whether or not to try it.