For 2.5L Turbo Owners Only

[Oldwolf]

As much as I hate to ask this...

Do you go with the 5000 mile oil change intervals as recommended in the manual, or do you go for fewer miles between OCI's.

I am sticking with the 5000 miles for now...unless you convince me of something else!!!


****** OCI's and Oil Types as listed in thread **********
*********************************************
5000 – “Oldwolf”; Delvac 1300 15w40 (summer); M1 TDT 5w40(winter)
5000 – “TimFreeh” 15w40; Rotella (0-75k miles); Mobil 1 0w40 (75k-200k)
5000 – “bobodaclown” ; Rotella T Synthetic 5w40
7500 – “shertex”; Delvac 1 5w40 (might go to 10k oci)
3000 – “2.5-10”; Rotella 15w40
5000 – “2.5-10”; Valvoline Syn Blue
5000 – “oldiesel”; Rotella 15w40
7500 – “2.5Turbo”; M1 TDT 5w40
7500 – “Dana B.”; Various 5w40 synthetics

[Crazy_Nate]

An oil analysis should be able to tell you what you can do safely

[Oldwolf]

Nate - What is your OCI in your 2.5L Turbo?

[Crazy_Nate]

Well, since I just bought the vehicle, I'm coming up on the first oil change (3k with conventional). I'm switching to a 5W40 synthetic (have a couple gallons of Rotella T in the trunk), so, I'll send off an oil analysis to see where I stand when I get some sufficient mileage on it. I don't expect anything to be wrong with 5k miles.

Oh, BTW, I have a 3.0L Turbo - I just expect the OM603 to be very similar to the OM602.

[TimFreeh]

My daughter in law inherited my 91 300D 2.5 turbo a couple of years ago. At this point the car has logged over 200K miles of service in our family. I've always used the standard 5K oil change intervals and I suspect its a very conservative interval.

I've had exactly zero problems with the engine internals, the head gasket is original but I did replace the timing chain about 120K miles ago due to a TSB that identified potential problems with timing chains in early OM602 engines.

This car still runs perfectly and uses no oil between changes.

[Oldwolf]

That's very informative information Tim. What weight oil do you use in the Winter and the Summer?

[TimFreeh]

According to my records I used 15-40W Rotella for about the first 75K miles of service and I switched to Mobil 1 0W-40 in late 2002. Its only had Mobil 1 0W-40 since that time.

I keep expecting something to go wrong with the engine, but cross my fingers it just seems to keep on running.

It's a great car, when my daughter in law finishes with it I think I'm going to keep it around as a spare car. I'm kind of curious to see how long it will continue to run!!

[Oldwolf]

That Mobil 1 0W-40 has me confused. Mobil even recommended it to me but It is only CF rated. I guess it works dandy since you have been using it for 125k miles. I guess I don't have to stick to CI or CJ.

[TimFreeh]

Originally Posted by Oldwolf

I guess I don't have to stick to CI or CJ.

I'd guess when the OM602 came off the assembly line all they had was CC or CD rated oils. Petroleum companies are constantly improving oils and additive packages and the oils available today are light-years better than what was around in 1991. Mobil 1 0W-40 has the MB 229.5 certification so I can use it in any of my cars, I use it in everything except my Dodge/Cummins truck.

I don't want to start yet another silly oil-thread but pretty much any modern diesel rated multi-grade oil will work just fine given 5K change intervals. If you want to try extended drain intervals with sampling than maybe I'd look for the absolute "best" oil I could find at the time.

People worry way too much about oils.

[Oldwolf]

Originally Posted by TimFreeh

I don't want to start yet another silly oil-thread but pretty much any modern diesel rated multi-grade oil will work just fine given 5K change intervals.

People worry way too much about oils.

Ha! That was why I "hated to ask this" question..

But it sure helps hearing what other people have done with the same model MB that I have.

Thanks for the info.

[bobodaclown]

I'm using Rotella T Synthetic 5W40 in my 92 300D changing it every 5K. So far so good.

[shertex]

Originally Posted by Oldwolf

As much as I hate to ask this...

Do you go with the 5000 mile oil change intervals as recommended in the manual, or do you go for fewer miles between OCI's.

I am sticking with the 5000 miles for now...unless you convince me of something else!!!

I own two of them. Did an oil analysis on the 92 after 7500 miles using Delvac 1. Soot was 0.8%. Everything else was well within limits too. So I'm planning on 10,000 mile intervals.

[Oldwolf]

Originally Posted by shertex

I own two of them. Did an oil analysis on the 92 after 7500 miles using Delvac 1. Soot was 0.8%. Everything else was well within limits too. So I'm planning on 10,000 mile intervals.

Amazingly low soot levels there Shertex.

My "MB Bible" says that Turbos should always be considered to be operating under "severe conditions" and the oil changed every 2500 miles.

Ever since I read that I have been second guessing the wisdom of my 5000 mile OCIs.

So far I use Delvac 1300 15W40 in the warm months and M1 TDT 5W40 in the winter. It's beginning to sound like my engine will be perfectly fine with a 5000 mile OCI.

[2.5-10]

my rule is 3,000 miles for the 15w-40 rotella or 5,000 miles for the 5w-40 valvoline synthetic blue.

OEM filters only

I could go further since the whole system in my car takes 11.5 quarts of oil.

[Oldwolf]

Originally Posted by 2.5-10

my rule is 3,000 miles for the 15w-40 rotella or 5,000 miles for the 5w-40 valvoline synthetic blue.

OEM filters only

I could go further since the whole system in my car takes 11.5 quarts of oil.

Did you enlarge the crankcase pan?

Why are those OCI's your rule with the 2.5?