mobil 1 oil concern.....

[mblair]

Two months ago I changed the oil in my 93 W250. I also changed the air filter. I used a Fram oil filter and air filter. For oil, I used some 15w-50 mobil 1 Tri-Synthetic. (It has the "CF" rating and was only $9. 00 for a 5 qt container at walMart on clearance) I checked the oil today, about 1500 miles and 2 months later. The oil was still up to the full mark,but IT WASN'T BLACK!?. It looked like oil out of a gas engine just before it needs to be changed. I couldn't feel anything in it either. The engine has 212,000 miles.

The reason I am concerned because of the six different makes of dieselsI've owned, this is the first the oil hasn't gone black soon after oil was changed, including this truckwhen I changed it before putting this in. ( I usually change oil and filters at 3000 miles) I can only think of three reasons why this might be.



1. The filter is so good (I doubt it)



2. The oil is so good it's not breaking down and is sealing so well it's keeping blowby down. (current rating is ch-4,right?)



3. It's not doing it's job of suspending dirt and soot from blowby in oil as I understand detergent oil is supposed to do.



I'm concerned that it may have something to do with #3.



Anyone's thoughts on this??? I know there are many many people knowledgable about oil out there. Thanks in advance for anyone taking time to reply. Max.

 

[LSMITH]

My opinion is that the CF oil has less detergency, so it is not cleaning and suspending the garbage as well. I have been changing my oil every 3K miles for the last 20K or so, and I changed every 6-7K before that. After a few 3K mile runs the oil is nearly clean when I change it now, it used to get black in 2K miles with the same oil (Delo 400). I would switch to Delvac 1 if I wanted the maximum detergency and stay in a off the shelf synthetic.

 

[Dieselnerd]

You should never use a FRAM filter on a Cummins. They are not on the Dodge/Cummins approved list, they can and have broken down and clogged the piston cooling nozzles which destroys your engine. This has been discussed on this forum many times. They are not built to withstand the vibrations of a diesel.

 

[Vaughn MacKenzie]

LSmith, just curious why you change your oil so often. Unless you never take trips on the highway and always just putt around town, 3K oil changes are a waste of oil IMO.



When I ran standard oil I usually went 7,000+ and when I sent in samples they came back so good I could've gone 10K easily. Perfectly good oil can be black as coal.



I now run 20k oil changes on synthetic and the samples always come back great showing lots of life left in the oil. Other than soot diesels are not as hard on oil as gassers (much less contamination).



But of course it's your truck and you can do whatever you please with it



Vaughn

 

[LSMITH]

Vaughn, I change it every 3K miles these days because I have a small coolant leak into the oil. I am going to replace the headgasket as soon as I get some time.



The leak I have is just enough to deplete the TBN to 50% in 4K miles, no wear metal troubles or any of that. Before the leak I was on a 6-7K miles change routine and was dumping perfectly good oil when I changed it. With my driving I could have easily gone to 10K miles with dino oil.

 

[Vaughn MacKenzie]

LSMITH, that's a darn good reason to change it every 3K!



I had a Bronco 2 with a cracked head I didn't know about, I noticed I had to add coolant every couple of months and was concerned about it but couldn't find a cause. Did the radiator/exhaust detection test which was negative.



Eventually I started getting lifter noise, my oil pressure gradually dropped and then I started getting a lot of bottom end noise. I tore the motor down and the bearings were wasted and there was a hairline crack in one of the heads. I guess the 2. 9 Fords are notorious for this problem.



I know you'll rest easier once you get the gasket fixed but at least you're checking the oil.



Vaughn