Oils ain't Oils - how true ?

[John S]

A valid question Fotografa. Mobil 1 is a very good synthetic oil that Mercedes recommnends for their cars, while the 15W 50 has been used extensively in W116's for some years by Mercedes mechanics who have had their own business in the USA and Hawaii - they swear by it.

 

[BenzBoy]

A valid question Fotografa. Mobil 1 is a very good synthetic oil that Mercedes recommnends for their cars, while the 15W 50 has been used extensively in W116's for some years by Mercedes mechanics who have had their own business in the USA and Hawaii - they swear by it.

That is also my understanding too John. M-B dealers of course use only Mobil 1 but the agreement to do so will finish in the next 2 years and it will be interesting to see what is then the M-B recommended product. Already Mobil has ceased supplying bulk oil to independents in Australia and Castrol has taken their place.
One thing I could never understand is why the supposedly same oil at a delaer is twice the price as it is at K-Mart. I am told by M-B, Mobil reps and some independents that it is a higher quality than what Mobil sells through retail shops. Now if that is so, what happens to all the higher quality oil now that it is no longer sold to independents?
Even Catrol markets two ranges of Magnatec; that which is sold at normal rtail outlets and one labelled Magnatec Professional sold to independents.
I suspect the truth is not quite out there yet on the marketing score...
Regards,
Benz-Boy

 

[Styria]

Gentlemen, just to be a "smartie-pants", let me remind you of Oscar's 350SE maintenance record. It had never seen any better oil than Castrol XL in its entire life, and at 370K. odd kilometers, it still managed to show 150lbs./sqin. on all cylinders - it might even have been 175 ! Therefore, just maybe, the secret is to change the oil frequently - never mind what you're paying for it ! ?..quasi question....

There are two things I do know for sure - one is my experience with the Statesman, and the second refers to the use of the $28.00 per 5 liter Shell Helix in the blue bottle, and of course the Castrol Magnatec. On long, fast trips, when running with Shell, the rear bumper would always be coated with an oil film - similar running with the Magnatec left the bar free of that oil film. That has got to mean something. Regards Styria

 

[Styria]

Regarding to what JohnS is saying - it will indeed be interesting to see what transpires at the end of the contract between MB and Mobil. Also, it'd be curious to know their per liter price, and what they are selling it for.

I also wonder if in fact there is any difference in the quality of the oil between wholesale and retail...hmm. Styria

 

[Fotografa]

Gentlemen, just to be a "smartie-pants", let me remind you of Oscar's 350SE maintenance record. It had never seen any better oil than Castrol XL in its entire life, and at 370K. odd kilometers, it still managed to show 150lbs./sqin. on all cylinders - it might even have been 175 ! Therefore, just maybe, the secret is to change the oil frequently - never mind what you're paying for it ! ?..quasi question....

There are two things I do know for sure - one is my experience with the Statesman, and the second refers to the use of the $28.00 per 5 liter Shell Helix in the blue bottle, and of course the Castrol Magnatec. On long, fast trips, when running with Shell, the rear bumper would always be coated with an oil film - similar running with the Magnatec left the bar free of that oil film. That has got to mean something. Regards Styria

I think anecdotal evidence has it's place, but it must be remembered that not all our cars have had the same treatment up until this point, and I believe it pays to look at getting the oil that best matches your engine's current condition, as well as the environmental and driving conditions that your engine will experience.

I've quite often seen cars with excellent compression, no leaks, etc, that after an engine flush develop compression drops and leaks. In that case, is your oil preventing a problem, or just masking it?

It's all food for thought.

 

[John S]

I have seen other list discussions on the price / quality of Mobil 1 which is sold through discount chains and dealers, and the consensus has been that it is exactly the same oil - the price difference is mainly associated with the lower purchasing volume of the dealers and the overheads. This seemed logical to me.

 

[oscar]

Gentlemen, just to be a "smartie-pants", let me remind you of Oscar's 350SE maintenance record. It had never seen any better oil than Castrol XL in its entire life, and at 370K. odd kilometers, it still managed to show 150lbs./sqin. on all cylinders - it might even have been 175 ! Therefore, just maybe, the secret is to change the oil frequently - never mind what you're paying for it ! ?..quasi question....

Well actually, after doing some research and studying the maintenance record to respond I'm surprised and happy to see how cared for the car was originally. The abuse happened between say 1994-2004 approx. But from new, oil changes put my regime to shame:

First bought by a farmer in Guyra NSW from Armidale dealer 22/12/73, Castrol GTX has been used at 700, 1472, 2300, 3900, 6000, 7512, 9425, 10800, 12309km and it goes on and on until 52,719km in 1983 where Castrol LX is used. 52,000km in 10years, not bad and too many oil changes to count.

There was a change in ownership but I can't find exactly when but the service intervals blew out. March '84 56899 then Oct '86 80092km Castrol FMX. 5000km changes approx from then on until 1990, all on FMX.

In 1990, it was bought by my dad for $25,500 with 122,322km on the odo. Serviced by MB dealer in Tamworth 4 times using "Shell Super" up until 1993 with 152,414km.

It was after that my dad started using non MB mechanics for simple servicing and keeping a bottle of whatever-oil-was-cheap-from-BigW in the boot. Pretty soon the car was travelling all over the place between Tamworth, Armidale, Newcastle, Syd and Wollongong, doing a lot of towing as well and racked up another 200,000+ over the next 10yrs with very few receipts. Oil was only topped up and only changed if something else needed fixing with the car. It was being neglected mechanically and cosmetically, did the Uni rounds and was a second car not worth much. For a couple of years the odo stopped working whilst still doing around 20,000 a year.

So I get it around 2005 with 370,000km+. Whilst it's showing 393,000km now, I figure it had already easily done over 400k. But yes, compression around the 150-160 mark last time I did it. Heads have never been removed, valve stem seals and timing chain perhaps the most extensive repair when it comes to work on the engine. I've questioned if the longevity is due to the care during its early life, a testament to mercedes engineering, or just pure luck. Perhaps a mix of the three. Am I inching towards engine failure as I try to reach 500,000km and brag about how good the engine is. Maybe I should jump off the full synth wagon and go Castrol GTX frequently.

 

[TJ 450]

Castrol GTX frequently is what both my 450 is being treated to and what my 6.9 will be treated to. The 450 has excellent compression figures (between 165 and 170PSI) and has done 350,000KM. It has had dealer servicing up until 1999 and is now on its third timing chain. Oil has been Castrol GTX, FMX etc.
It is now running very smoothly... the fouled plugs and resulting miss were due to a blocked fuel distributor.

My 6.9 was treated to MB servicing until 1988, using Castrol GTX/FMX. Since then it's anyone's guess as to what's been done, if anything. Taking into account that the car was first registered in 1981, that's only seven years of proper servicing and when I received the vehicle, it still had the 1988 oil filter installed! It has covered about 100,000km since 1988 and was practically run into the ground.

Despite all this, the engine is excellent with over 165PSI compression and is very clean inside.

Fortunately these are such well-engineered vehicles, that the basics remain sound even through years of mechanical neglect.
Frequent oil changes will only prolong the life of components even further.

In my experience, the main difference between quality oils appears to be marketing. With Mobil products, whilst they may be excellent if used from new, I have never had great confidence using them. I seem to experience increased engine noise and oil consumption every time.

Tim

 

[AAB]

Tim,

My 450 is doing a bit of missing at idle speed, so could you tell me where the fuel distributor is please ?

It goes O.K. for a few days after an " Italian tune up ", but around the burbs at 60 kph, it reverts back to the miss.

Regards,

Alex

 

[John S]

It may pay to check your ignition leads.

 

[abl567]

It may pay to check your ignition leads.

An easy check is to run the engine in the dark, with the bonnet up and look for leaks to earth (sparks)

 

[SEL_69L]

As I understand it, Magnetec was named that way, because that oil has a greater amount of detergent in it. This allows a residual oil film to remain on the cylinder walls and in the valve guides, thus providing extra protection at cold start-up, at the time of greater wear. If the allegation that the major oil companies are selling their oils in two classes of quality, and the better quality is going to their preferred outlets is correct, then I think that Styria's policies on oils seem good. Castrol has an enviable reputation as indepent oil supplier. Incidentally I looked at Castrol's website and found their reccommendations for the 6.9. Here they are: Engine: Magnetec 10W-40. (My opinion is that this is preferable), alternatives: GTX2 20W-50 modern engine, GTX3 15W-50 modern engine. Transmission: Castrol Transmax M. Diff.: Castrol Hypoid Long drain; (distinctive smell, this product is sulphonated, like most diff. oils) Power steering: Daimler Chrysler approved (Part No. 000 989 8803.

 

[TJ 450]

Hi AAB,

The fuel distributor is probably one of the last things you should consider when troubleshooting some sort of missfire. They are usually very long lived and are quite expensive to buy new. In my case, the strainer on the inlet had been removed at some stage and I think some foreign matter entered the system when I changed the fuel filter, causing the partial blockage to cylinder #5.

I would go with John S' suggestion and check the plugs... the fact that it runs fine after a bit of a blast suggests that the plugs are not remaining clean for whatever reason.

If you are keen to investigate further, I would start a new topic.

Tim

 

[Styria]

Castrol GTX frequently is what both my 450 is being treated to and what my 6.9 will be treated to. The 450 has excellent compression figures (between 165 and 170PSI) and has done 350,000KM. It has had dealer servicing up until 1999 and is now on its third timing chain. Oil has been Castrol GTX, FMX etc.
It is now running very smoothly... the fouled plugs and resulting miss were due to a blocked fuel distributor.

My 6.9 was treated to MB servicing until 1988, using Castrol GTX/FMX. Since then it's anyone's guess as to what's been done, if anything. Taking into account that the car was first registered in 1981, that's only seven years of proper servicing and when I received the vehicle, it still had the 1988 oil filter installed! It has covered about 100,000km since 1988 and was practically run into the ground.

Despite all this, the engine is excellent with over 165PSI compression and is very clean inside.

Fortunately these are such well-engineered vehicles, that the basics remain sound even through years of mechanical neglect.
Frequent oil changes will only prolong the life of components even further.

In my experience, the main difference between quality oils appears to be marketing. With Mobil products, whilst they may be excellent if used from new, I have never had great confidence using them. I seem to experience increased engine noise and oil consumption every time.

Tim

In my experience, the main difference between quality oils appears to be marketing. With Mobil products, whilst they may be excellent if used from new, I have never had great confidence using them. I seem to experience increased engine noise and oil consumption every time.

Hi TJ450, are you referring to your 450 in this instance ? It is interesting that you mention increased engine noise and oil consumption. Regards Styria

 

[TJ 450]

Not so much the 450, but both of my previous Volvos. The two Volvos were completely different cars... one had the V6 with solid tappets and the other was the I5 with hydraulic lifters. Both experienced annoying top-end noise after a stint of using Mobil 1 5W-50 and Synth S 10W-40, even after adjustment and inspection.

Using the same oils in the 450, I experienced some increase in engine noise, but nothing drastic.

I suspect it has to do with the viscosity or maybe it just cleaned out sludge that was taking up the clearance.

Either way, the results appeared to be negative, so I reverted to Castrol GTX 20W-50 for the 450. I've never experienced anything disconcerting with it.

I might give the Magnatec a try in my 6.9 after I've flushed it out with GTX. I should be able to start the beast in a couple of weeks time.

Tim

 

[Des]

This cheeky old fellow says use BP motor oel or else!

 

[Styria]

Well Des, marketing certainly has not changed during the last eighty years. Even in those days, the company claimed double the period between oil changes, but did stress that it should be done once per year irrespective of mileage.

BTW, where on earth did you discover this picture ? Regards Styria

 

[Styria]

Even this little girl was part of the oil marketing ploy back in 1949. Picture courtesy of National Geographic magazine I bought on my recent trip to 'sleepy' Maitland.



Regards Styria

 

[BenzBoy]

Hmmmmm - Matthew Arnold would turn in his grave to see how his writing has been quoted for such an advert. But then, that is another story from another time and place...
Regards,
Benz-Boy

 

[carl888]

Funny thing about oils. The only way to test an oil is to run it and do a particulate analysis. Some basic facts, full synthetics beat any mineral grade hands down. The net abounds with tests, have a look for yourself.

The other thing that's important, never confuse oil pressure and oil flow. You should aim to maintain the manufacturers oil pressure, no more. (Usually about 1.0 bar per 1,000 rpm) If you have too little flow, ie high pressure, the oil will run hotter because its circulating slower, and worse, as the revs rise, the flow won't increase, it will simply flop back into the sump through the bypass valve and never make it to the engine!

Finally, if your engine consumes oil, its just worn, rebuild it.

When I took over the maintenance of the 300TD at 390,000 kms I was specifically warned against synthetics. The "Mechanic" said it would run out of the engine! He thought I was joking when I said I was going to run it on Shell Helix Ultra 5W-30. Well, I did ultimately , and have ever since, and this is the mileage now:



I started with a 10W-60, then went to a 5W-40, then settled on the 5W-30. Interesting, with each decrease in viscosity, the car consumed 1mpg less fuel.

The other nice thing about synthetics, is when you pull the cam covers off, they look like this:



Regards,

Carl.