Where does it come from?

[BADBIRDCAGE]

I was at dinner with friends a couple of nights back and I mentioned that I was going to switch to Valvoline Synthetic Diesel 5w40 in my motor. I currently run Mobil 1 5w30.

One of my friends said to be VERY careful doing such a thing as his understanding is that the high detergent content in the diesel formulated oil could wash the bearings dry.

Sooo, they physical properties of forcing lubricant at pressure between a crankshaft and a bearing are different in a gasoline crankcase than a diesel crankcase?

Where does this come from?

(I told my friend that I would not hold him responsible if my bearings failed from the oil change)

Rich

 

[Hib Halverson]

You're pal knows little about engine oil

In fact, a diesel engine oil is an excellent choice for a flat tappet engine.

Everything you (and your pal) need to know about engine oil for older engines is right here on the CAC at: CAC's Comprehensive Look at Engine Oil and Flat-Tappet Camshaft Durability

 

[BADBIRDCAGE]

Hib: Thanks for the response. I run a full roller motor (all the way through the rocker arms) but that is immaterial on this one. I haven't been in the engine rebuilding business for many years now but I failed to see where my friend was going with this one.

Rich