W123 Turbodiesel oil; Mobil 1 15W-50/5W-40 turbodiesel? Others? Dino?

[johnd]

In my garage there rests a jug of Mobil 1 15W-50 which I bought two months ago intending to use in my Bimmer, which has been garaged since my daily driver's become a 300DT two weeks ago.

The 300D really needs an oil change, and I'd like to do it this afternoon or tomorrow. The question is, should I use the 15W-50 or get some turbodiesel oil from the truck stop? And on the same subject, should I be using synthetic or dino in a 617 which has been running dino its entire life, and hasn't had its rubber changed in ages? It's currently running well enough, albeit a 1qt/1000mi leak, that it'd kill me to start a lot of other leaks by unclogging sediment with synthetic -- if that isn't just an old wives' tale, that is. If it isn't, she could sure benefit from any advantages synthetic provides. I'm going to be driving in 100+F weather all summer.

[Hatterasguy]

Mobil 1 15w50 is just fine.

[uberwgn]

john, do you have enough 15W50 to perform a complete change? The old product carried several specific diesel ratings. They've re-formulated and the new 15W50 doesn't carry the rating it used to.

[johnd]

Originally Posted by uberwgn

john, do you have enough 15W50 to perform a complete change? The old product carried several specific diesel ratings. They've re-formulated and the new 15W50 doesn't carry the rating it used to.

Aha! I thought it was a jug, but it's four quarts. Rear panel reads:

A3, B3/B4
API SM/CF
API SERVICES SM/CF
SAE 15W-50

According to Mobil's site, while 15W-50 "also meets the requirements for diesel powered vehicles where an API CF or CD oil is recommended," Turbo Diesel Truck 5W-50 "Meets CI-4, CH-4, CG-4, CF-4 and CF."

Do the ratings matter with 617s? I think I'll risk one more day to nose around for the 5W-50 and save the 15W.

[Hatterasguy]

As long as it is CF rated its fine.

[johnd]

Ace! Thanks.

[bud640]

Originally Posted by Hatterasguy

Mobil 1 15w50 is just fine.

I agree, good oil.