Amsoil makes a 5w30 diesel oil that i had used in the past with good results. As long as its for a diesel it will probably be fine.

 

What makes you think your truck needs flushed? Why not leave the oil in it there until you get your new oil from Liquimoly? IMO, it seems like you would be wasting good oil for no reason.

just my $0.02

 

Because I've got loads of it. It'd give me something to do. We've had our 2 weeks of hot temperature now. It's back to typical british weather of torrential rain and 68 degs. But if its good as Coolbreeze says, I'll run it over winter then change it come springtime.

Thought that just a flush would get all the "old" oil and displace what draining wouldn't get rid of.

Anyway - Can put the 5w30 to use.

Cumminsturbofreak - I'm surprised that Merc oil isn't cheap over your side, Its stupidly cheap here, Kind of one of the best kept secrets. They advertised on ebay, sales went nuts. Can't understand why or how they sell it so cheap!

 

I would certainly buy it for use in my W211 OM648… thing is, the pond between us is pretty large…

Anyways, since you’re in the relatively temperate UK, just go ahead and run it to full interval. You really don’t need thick oil in these engines until you operate in 90-100*F weather…

 

During cool temps, a quality 5-30 should be fine.

 

We run 10-30 in our big rigs, with no issue they run 1 million plus miles.

 

I don't remember what I use in my lawn mower...but it's irrelevant.

 

It should show on the label to use a CF-4 or CJ-4 compatible oil as per Cummins recommendations

 

When I 1st bought my 2004, I ran conventional 15W-40 in the summer and conventional 10W-30 in the winter.
When the engine was hot, I could see much lower oil pressure with the 10W-30.
I have a real/aftermarket oil pressure gauge in my truck.

I wouldn't run 10W-30 or 5W-30 in the hot summer while towing or heavy loads in the older engines.