Straight 50W Oil in a 603??? - PeachParts Mercedes-Benz Forum

aroohk · #1 12-03-2005, 07:04 PM

I went to a local (WELL RESPECTED) Mercedes Shop in Southern, CA. I talked to the tech who was impressed with my 1000.00 300SDL that I have been driving around for the past month. I asked him about oil and he said he did not like Synthetic, and he preferred straight 50W Penzoil. I have always been told NO PENZOIL cause of the PenStar Molecule actually being parafin. He said he liked 50W in the cars when they get over 100K miles or higher in miles... but that did not make sense to me. I was going to run a good 15w40 synthetic in the car just to keep the lifters nice and quiet and NOT clogged. I have almost 411K on my car, and it runs great... Give me some feedback guys and let me know what you think. I run Castrol Syntec FULL Sythetic in my BMW since that is what was recommended by the factory in a 5w30 FULL SYNTHETIC oil. This guys was all about 3K mile oil changes... GAK! I went with Synthetic in my Explorer cause as a daily driver I put 3K a month on the thing and was not into changing the oil once a month. I have no problem doing oil changes in the 6-7K range since I prefer the quality of the synthetic oil for this reason...

I need food now and will start to babble soon, so please feel free to give me some pointers. Has anyone ever heard of such a thing in a modern car such as the SDL? (I mean relatively modern...)

Peace
Aaron

RobTheMod · #2 12-03-2005, 07:28 PM

I would not pick an oil that heavy. Diesel-rated 40W for hot summers, maybe. 15w40 Rotella or Delvac, sure.

boneheaddoctor · #3 12-03-2005, 07:32 PM

I'm surprised that would work....you ever see 50W oil in sub 40 f weather....?

its like honey in thickness at 20 degrees....

My Harley runs 50W oil.....but remember every bearing in that engine is a roller bearing....not at all like the bearings of a car that rely on a cushin of presurised oil to keep things appart.

Jim H · #4 12-03-2005, 08:23 PM

Last engine I heard of that used straight 50W was a Harley.

Any multigrade weight recommended in the M-B Owner's Manual should do just fine.

300SDog · #5 12-03-2005, 08:35 PM

Lemme guess, this "expert" socal mercedes shop spends 85% of its time dealing with gasoline engines and that's what their reputation is founded on.

Lesser known fact, dirty diesel engine oil can have gelling problems same as diesel fuel. Their idea for straight 50wt this time of year in your diesel engine is formula for disaster. LOL, you'd even do better with straight 30wt instead of what those eggheads are recommending.

And just for grins if/when you go back to this joker at the socal mercedes shop, ask him if Pennzoil straight 50wt is diesel rated. And then ask him to xplain the difference between diesel rated oils and those that arent...... oops, the guy who recommended straight 50wt doesnt know.

dieseldiehard · #6 12-03-2005, 08:59 PM

The weather is not all that cold in Orange County so your oil will not gel but the problem is straight non diesel rated oil doesn't have the additives that keep soot in suspension so I don't know whether your lifters are going to like it or not.
You should avoid that mechanic and use 15W40 synthetic in your 603 engine.
With 411K on it I'll wager the rings are a tad worn (mine were at 260K) How much oil is the car using?

aroohk · #7 12-04-2005, 02:19 AM

Quote:

Originally Posted by 240DieselDog

Lemme guess, this "expert" socal mercedes shop spends 85% of its time dealing with gasoline engines and that's what their reputation is founded on.

Lesser known fact, dirty diesel engine oil can have gelling problems same as diesel fuel. Their idea for straight 50wt this time of year in your diesel engine is formula for disaster. LOL, you'd even do better with straight 30wt instead of what those eggheads are recommending.

And just for grins if/when you go back to this joker at the socal mercedes shop, ask him if Pennzoil straight 50wt is diesel rated. And then ask him to xplain the difference between diesel rated oils and those that arent...... oops, the guy who recommended straight 50wt doesnt know.

He has been around for ages... when EVERYONE in so cal seemed to drive 240D's and 300SD's... he said he has actually owned a couple of SDL's... BUT I am inclined to just go with the Synthetic 15w40 for here...

Thanks for the feedback... he is a good mechanic, BUT I was just really surprised he said that... He does work on a lot of older diesel benzes tho...

aroohk · #8 12-04-2005, 02:24 AM

Quote:

Originally Posted by dieseldiehard

The weather is not all that cold in Orange County so your oil will not gel but the problem is straight non diesel rated oil doesn't have the additives that keep soot in suspension so I don't know whether your lifters are going to like it or not.
You should avoid that mechanic and use 15W40 synthetic in your 603 engine.
With 411K on it I'll wager the rings are a tad worn (mine were at 260K) How much oil is the car using?

I have checked the oil after the last 1000 miles and it is pretty much right where it should be. This car (regardless of the miles) was BABIED by the former owner... He spent an average of 3-4K a year on just staying on top of everything... I think one of the reasons I got the car so cheap is the mechanic was tired of dealing with the owners anal tendancies... It was a different mechanic, and he was quite skilled in working on Mercedes Automobiles...

I was going to use that Mobil 1... I think its the Delvac? OR see if Castrol has a Diesel rated synthetic since I have been VERY happy with the Syntec in the BMW...

Heck running 5w30 Synth in my 1995 Explorer i used BARELY a quart in 13000 miles... it was a few months of REALLY long crazy highway driving... and that was a truck that had over 150K on it at the time... I know the synth does not break down, since in the newer MB's and BMW's if you follow the computer they can go 15K on an oil change... (tho I dont like to do that...)

Hatterasguy · #9 12-04-2005, 10:03 AM

Mobil 1 15w-50 is as heavy as I would go. I ran that stuff for a year, even in below zero temps starting was not a problem.

Now I switched to Delvac 1, it has all the latest CH ratings from the API. Seems like a slightly better oil.

Red Pike · #10 12-04-2005, 12:06 PM

The probable reason for him recommending 50W oil is that, in an older engine (one with more miles = more wear) is to improve compression on an engine in which the rings and cylinders are worn.

t walgamuth · #11 12-04-2005, 12:44 PM

he might not be that far off in ca but i wouldnt use it if not diesel rated.

around here straight 50 wouldnt work except in summer.

i had straight 40 or 50 in my bmw cycle once and tried to kick start it in the winter. i could barely turn the engine over at all. drained it out and put in 10w30 and started it right up. 1.75 qt. i think.

tom w

#12 12-04-2005, 12:48 PM

Tom, do you still ride your beamer?

t walgamuth · #13 12-04-2005, 12:54 PM

it was a 72 r60/5. i had it for about 7 years. when i got to be about 35 with three kids and a business to run i decided it didnt make much sense to keep it sitting around in the garage and not being ridden to sell it. i think i sold it for about 350. those are worth over 2k now. i still itch to ride now and then but when i think of how long it would take to heal from a minor accident i put it out of my mind. i always marvel at folks my age and older riding around on those ubiquitous harleys.

it was a very nice high quality bike. it felt like a benz on two wheels.

so, you have one?

tom w

#14 12-04-2005, 01:02 PM

I'd love to have a 72 r60/5 now. I have a 83 R80ST, which is a great bike (only about 1000 were imported), but every once in a while I'm tempted to buy an early 70s beamer. But I don't ride enough as it is, I couldn't justify another bike.

What's wrong with old guys riding?

t walgamuth · #15 12-04-2005, 01:23 PM

i am just too chicken.

tom w