Originally Posted by pastorscott
My 97 TJ had close to 170,000 miles. I live in NY where it can get real cold.
Its my 1st year with the Jeep. This summer it was great, running 10w40. does not burn a drop of oil or leak a drop. Is 10w40 too thick or maybe 10w30 or 5w30. which brands and how about the high miles oil types..
or should i just stick with the 10w40-- or how bout these 5w40 types
50%-70% of all engine wear happens at cold start up from oil starvation.
The first number is the cold viscosity index. The lower the number the lower the viscosity, the easier it will flow to your bearings in cold temps. The sooner your bearings get oil the better. The second number is the hot viscosity index. The higher the number the better it will old up under hot operating temps.
It gets to 10-20 degrees easily in NY so I would definitely go with 5W-30.
I don't use their products but their website has a good explanation of how to read oil numbers. Here is a link.
Motor Oil Viscosity Grades Explained in Layman's Terms