Delvac 1 - PeachParts Mercedes-Benz Forum

#1 04-24-2003, 10:27 AM

Greetings all. The previous owner of my '86 300 SDL and I have ALWAYS used Delvac 1 (5-40w) synthetic engine oil. He ran low average miles on the vehicle while I STRUGGLE to get 2,000-2,500 miles a year on the clock now. I have been changing the oil twice a year but am wondering if I am wasting money (at $20/gallon) plus filter, time or labor.

I am completely sold on using Delvac 1, but wonder if I can get away with an ANNUAL oil and filter change. Any insights you can offer are appreciated!

TN-W124 Diesel · #2 04-24-2003, 10:42 AM

I change mine one time per year since I have changed over to Mobil Delvac. But my mileage is less than 10K...

rwthomas1 · #3 04-24-2003, 06:36 PM

My biggest concern since you are not using the car much is that when you do use it you drive it long enough to completely warm up and burn off any condensation, etc. that has accumulated in the oil. That said I think in your application once-a-year oil changes would be perfectly acceptable. RT

Rick Miley · #4 04-25-2003, 09:39 AM

2000 miles a year doesn't really tell the whole story. Is it a lot of small trips? Or does the car sit unused for long periods of time between being driven?

If it's small trips often, I would go ahead and change the oil twice per year because that type of use is really hard on oil.

If the car sits, that's a little easier on the oil, but you will still get condensation. You should make time to take it out for a drive once a month or so. Make it a half hour or so at highway speeds. And change the oil in the spring when you do your brake fluid flush (you're doing that, right?) because winter is the worst time for condensation.

Speaking of which, you should keep the fuel tank as full as possible to prevent condensation there as well. That will help prevent algae from growing in the tank.

md21722 · #5 04-25-2003, 11:38 AM

When you use the car, if you drive it for a half hour or so to get both coolant & oil hot then 1 year is fine. Otherwise, I'd change it every 6 months.

oldsouth · #6 04-26-2003, 12:01 PM

Take an oil sample and have it analyzed. You local Caterpillar dealer can do this for under $10. I use Delvac and change every 7500 miles but I do drive a lot.

rivermasternc · #7 04-26-2003, 06:51 PM

TigerTank:

Do you think if I changed to Delvac 1, I could go to a 12 month interval on changes? I'm currently using a dyno oil and have had to change it 4 times already this year! Very exhausting!

The 12 month interval will be in the 45,000 mile range.

gsxr · #8 04-26-2003, 07:04 PM

I once let my Delvac-1 stay in the crankcase for TWO years and 10kmi. The analysis came back excellent, as usual, no problems. I think 2 years would be about the limit I'd be comfortable with though. As mentioned previously, try to take the car on a longer trip (hour or two and freeway speeds) at least a couple times per year to let the condensation, etc boil out. Lots of short trips are bad for the oil, but that's one the reasons to use synthetic - it deals with it better than dino. My car gets to operating temps every time I pull it out of the garage, I never do short trips, so for me it was no problem.

Rivermaster, if you drive 45kmi per year

, you are the poster child for extended drain intervals with synthetic oil. Can you get 45kmi on one fill? I doubt it. That will depend on your engine's soot production level. You'll need to go 5-10kmi and have the oil analyzed, then interpolate the results to determine the maximum safe interval. For example, my '87 makes a bit less than 1% soot in 10kmi. That means I should be able to go 25-30kmi before I reach the 3% warning zone (and I think 4% is the absoulte maximum - not sure though). If you do attempt this, you cannot use cheap oil... you're looking at getting Delvac-1, Amsoil, RedLine, or other top-shelf stuff - not Castrol SynTec or Rotella.

Good luck,

rivermasternc · #9 04-26-2003, 07:42 PM

Hello Dave:

Thanks for the reply. I was just poking at TigerTank. We are related and at the opposite extremes of expected duty for our MB diesels.

der Dieseling Doktor chimed in on the oil issue again this week on the Ritter/Easley list. I'll post his comments for the benefit of others. TigerTank has already recieved a copy of this. The reply will reveal the gist of the question:

Quote:

----- Original Message -----
From: "Marshall Booth"
To:
Sent: Thursday, April 24, 2003 3:41 PM
Subject: Re: [MB] Re: Mobil Delvac-1

> Four or 5 years ago I first brought up the question about Mobil 1 and
> Delvac 1 to a Mobil tribologist, he and his collegues agreed that they
> didn't believe there was ANY good reason to use Delvac 1 in an MB auto
> diesel. The properties that distinguish D-1 from M-1 are NOT things that
> will make any difference in light duty diesel service (and automobile
> and pickup trucks are LIGHT DUTY). That particular engineer had owned a
> 123 300TD and had used M-1 in it since new and it then had 225kmi on it
> (original timing chain still on it with less than 2 deg of chain
> stretch). He could have used ANYTHING he wanted in his car and selected
> M-1 over D-1. He put his money where his mouth was and it worked for
> him. Delvac 1 is a more sophistocated product - blended to meet needs
> that an MB diesel simply doesn't require - and isn't expected to need.
> So to the question about whether Delvac 1 is "better" oil, the answer is
> a resounding "YES it is." To the question about whether that matters,
> the answer is a somewhat less emphatic - "probably not!" I use it
> because the 5W40 viscosity seem ABSOLUTELY perfect for use in MY cars as
> a year round oil. When 0W40 becomes easily available and equavalently
> priced with M-1 15W50, I will probably use 0W40 since there seems to be
> NO need for D-1 in my cars. For now I have M-1 15W50 in one car and D-1
> 5W40 in 4. ALL run GREAT.
>
> Marshall
> --
> Marshall Booth
> "der Dieseling Doktor"
> '87 300TD 168Kmi,'87 190D 2.5 210Kmi, '84 190D 2.2 226Kmi, '85 190D 2.0
> 156Kmi, '87 190D 2.5 turbo 217kmi
> Diesel Technical Advisor MBCA, member GWSection
> http://www.dhc.net/~pmhack/mercedes/mbooth1.htm

Hope this is helpful.

-Scott

#10 05-05-2003, 12:21 AM

Thanks to all.

I'm going to move to an annual oil change interval and keep an eye out for signs of condensation. I know in a gasoline engine with dino-oil the sign is a white color or froth in the oil. Is this the same symptom I should be looking for in the tiger tank?

Indeed, most of my trips are short and are around town errands but almost always the temp gauge reaches my normal operating temp (slightly above 80 degrees) before I shut it down.

It may well be that the engine reaches operating temp but the tranny does not. Not having a trans fluid temp gauge, I'm not sure how long it takes to reach operating temp. Is there a symptom I should look for there? I'm thinking that I may go ahead and do a trans fluid and filter change every year too, just to help mitigate any issues that my driving patterns create.

BTW, gsxr, I definitely get her out on the highway periodically for some "autobahn-style" cruising. Helps to remind me what this beauty is made for...EATING MILES.

JHZR2 · #11 05-05-2003, 10:29 PM

Analysis is the only thing that will tell you... Make sure you get the TBN or TAN (total base number, total alkalinity number) done so you can see how much additive is left, and also get the soot % and viscosity done to see if the oilhas taken too much on. I cant imagine it has though, in a well tuned, newer engine.
Ill be posting an analysis of delvac 1 in a normal drain interval of about 3 months, 4k miles in the upcoming months from out of my 83 300d... stay tuned

JMH