oil weight

[willy N.Y.]

I have a "40 9n. Is 10w40 ok to use? thanks in
advance for the help.

 

[Bruce (VA)]

Pick the weight of the oil by the condition of the engine (oil pressure) & the outside temperature. Many folks use 30w detergent all year. A straight weight oil is probably ok in a hot climate, but you will get excessive engine wear on startup in cold climates. (That’s one reason multi-vis oil was invented) And, I think most of NY can get pretty cold!

A worn engine is going to need a heavier weight oil to maintain oil pressure at operating speed & temp. Many use 10w30, 15w40 or even 20w50. Some like the newer diesel rated oil because of the additives for the flat tappets & highly recommend Shell Rotella T 15-40 (I'm not convinced that my 2400 rpm N engine needs the same oil as my 65 Mustang did) Anyway, IMHO, use a multi-vis detergent oil. Increase the weight if the engine has low oil pressure. And, BTW, switching to detergent oil is not going to loosen up the sludge in the engine. While choosing oil brands & weights are sometimes subjective, the use of detergent vs non-detergent shouldn’t be debatable given the oil available today.
50 Tips

 

[Devious]

Hi Willy I am building an engine now and will be rebuilding another soon and I will be using Rotella 15-40 and I will use it because it is recommended by lots of folks and because I have used it in my Big Truck engines for many many yrs with no engine problems due to bearing failures or other lube related priblems. My Truck now has 1.250 million miles on it now and at bearing check at 1 million miles, (Itook the pan down and 2 of the mains and 2 rod bearings down and inspected them and we were told by Detroit Deisel Motors to just put the bearings back on and run it some more.) The Shell oil company can t put out a product, for millions of high dollar end users, that might fail and cause the lawsuits to fly because their oil was at fault. I live in Houston where the winters are not bad and the summers are hot so 15-40 works fine for me. Just IMHO. Devious

 

[lha]

I also use 15-w-40 in my tractor,4x4 Nissan Hardbody,and a Toyota mini-Truck.Works well and maintains good oil pressure[40 psi hot,25 warm,15 after working the heck out of it]at idle.These # are the '41-9n.---lha