I know this topic has been kicked to death, but here's my story- Bought a 1991 300 D , 2.5 turbo last week lots of records of repairs and service, PO was using standard 10W30 until Aug. 2011. Changed to Valvoline synthetic blend 10W30. Ratings are SN/SM, GF-5. Should I change over to a diesel rated oil?
Thanks,
Rebel86

Yes.

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Present
1987 300SDL
1991 300SL
1990 560SEL
2001 ML320

Past
1969 200D 1979-82
1983 300SD 1984-85
1972 250C 1982-02
1995 S350 2011
1997 S320 2012

Isnt GF5 its diesel rating?

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

No. The GF-5 specification does not even address passenger car diesel engine use.

__________________
When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl.

Thanks, was mixed up with CF-5
Unless its got a C rating (CD, CF, CG, etc) best not use in a diesel.

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

I use Rotella 15W-40 in my 240D.

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1983 240D, 272K+ miles (odo broke)

Are any of those R.O. s (Repair Orders) [For Oil Changes] from a Mercedes Benz
franchised Dealership/Repair Facility ?

Are you saying the majority of the OM602.962's Oil Change(s) were with 10W30 GASOLINE rated Motor oils?

In Lynchburg the usual viscosity for your 124.128 would be a 5W40 DIESEL oil.
(Or a 15W40 DIESEL oil in the Summer months)

Howeveah,given your Motor's service history...I'd be using 15W40 CF rated DIESEL oil(At a minimum)
AND preferably 15W50 CF rated DIESEL oil (in the Summer a 20W50 CF rated DIESEL oil would not be too aggressive.)

A Diesel Engine Tears the V.I. index additives out of Gasoline rated oils rather
rapidly.AND Gasoline rated oils do not have the OTHER necessary additives that DIESEL rated oils do.

Please let us know how you get on.

Unsolicited Personal Lubrication Rota:
If:Shell Rotella T Fully Synthetic 5W40 [A.K.A T6] 3,000 Miles between changes.
If: Mobil1 "Truck and Turbo Diesel" 5W40 5,000 miles between changes.
If: Redline 5W40 5,000 miles between changes.
If: Lubrimoly 5W40 5,000 miles between changes.

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'84 300SD sold
124.128

I think the latest C rating is CJ 4 or something like that.

You need to use an oil designed specifically for diesel engines. Shell Rotella T, Mobil Delvac and Chevron Delo are the most common. Any one of these will serve you well. In most all US lower 48 climates, the most common weight 15W40 will be ideal.

Hope this helps,
Whip

Hey thanks for all help, MB dealers serviced this car early, then Midas Muffler brakes etc. Mostly Euro, MB dealers. Apparantly good care, car runs good, quite noisy when first started. Plan to have oil and filter changed and valve adjustment.
Good forum ,I have read and learned a lot, main reason I chose this model.
Rebel86
Ed

If your car is in good shape, you will end up loving the car even more than this forum. The W124 cars with ANY engine are a Master Piece of Mercedes Benz art and I am not referring to how the car looks. They drive beautifully and are really nice on the highway.

Whip

Spot on about the w124, to which I'd add the w126 too.....in the pantheon of great cars...from Mercedes Benz's glory days..

I actually have good examples of both.

~~~ 1991 560 SEC pearl black/black leather, bought in 1996 at MB dealer near Disneyland as certified pre owned, (guy that owned the Beverly Hotel's wife made him get rid of it "TOO flashy for Beverly Hills", he told me!!! 50k, for $39,000


~~~1995 E 420 almandine red/creme beige leather, bought in 2011, lifetime Cal/NM car, the personal ride of MB shop mech in shop that SPECIALIZES in the w124 body, 131k, for $2,995 cash.

EACH - with stamped books and almost ALL records, the jack, first aid kits, in place, full tool kits there.

EACH- Last model year (1991 and 1995) yearof production examples of the iconic Bruno Sacco body, styled to be recognized as nothing but a Mercedes Benz.

EACH - Top of the US line model in the respective W126 and w124 Mercedes Benz sales brochure - Burlwood, leather stadard, the most heavily optioned, expensive car in the model line you could order when new.

Each: "Cost no object" build quality ("The best or NOTHING") cars, can both run to interstellar mileage if taken care of, engineered to be easy to work on, top safety features of the time, can be kept as new for a lifetime and still LOOK new, still very safe, and rugged, last of the uncomplicated and pre- all computerized cars in the next body style that came in, unarguable "presence", durability, everlasting, stunningly beautiful, comfortable and always pleasure to drive..




I finally achieved it this last year: ONE good one of each body style: Total joy to get to decide daily which one to pick the keys to.

NO car payments either for over a dozen years either..

And never WILL be for the rest of my life. The plan is to keep both forever.

__________________
1991 560 SEC AMG, 199k <---- 300 hp 10:1 ECE euro HV ...

1995 E 420, 170k "The Red Plum" (sold)

2015 BMW 535i xdrive awd Stage 1 DINAN, 6k, <----364 hp

1967 Mercury Cougar, 49k

2013 Jaguar XF, 20k <----340 hp Supercharged, All Wheel Drive (sold)

WOOeee.... Beautiful couple of cars!

Whip

I have the same car (though it is a 1993) and have only been using 15w40 Delvac since I bought it some 40k miles ago. Prior to me buying the car, it got a steady diet of Castrol GTX. I think 10w40 but maybe it was 20w50. I'd have to check, but either way, I don't think they were diesel rated back then, nor now. It was changed at 5k miles each time by an Indy and sometimes a dealer. Go figure.

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1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

http://www.fuelly.com/sig-us/40601.png

Ah damn, now I want that Pearl black 1991 560 SEC, what gorgeous cars!
Rebel86

You want an API "C" rated oil. CF is still in use and would be OK, but is really an obsolete spec. Best is to use an HDEO, and while rotella 10w-30 would likely be OK in your engine, a 40wt is really optimal.

Id personally run rotella or mobil 1 5w-40. Otherwise you can run the Rotella T5 10w-30 if temperatures do not get too hot, or a 15w-40. Dont just run any 10w-30, it lacks the proper detergents and dispersants to protect your engine from soot.

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Current Diesels:
1981 240D (73K)
1982 300CD (169k)
1985 190D (169k)
1991 350SD (113k)
1991 350SD (206k)
1991 300D (228k)
1993 300SD (291k)
1993 300D 2.5T (338k)
1996 Dodge Ram CTD (442k)
1996 Dodge Ram CTD (265k)

Past Diesels:
1983 300D (228K)
1985 300D (233K)