Both of my Jeep 4.0's consistantly showed better wear numbers with XW-40. Using XW-30 tended to raise the iron numbers.
I had a feeling this would be the answer. However, it is not really true. Cheap dino 5W30 oils tend to shear down. Synthetics do not tend to shear down as much. (from what I have read on this board). Lastly, you have an oil like GC 0W30 with is almost a 40 weight at temp. It is probably thicker than any 10W30 at operating temp. So recommending a 5W30 dino oil is completely different than recommending a 0W30 synthetic. Now I am more confused. If this engine requires a thicker oil, wouldn't a better recommendation be something like:quote:
Yes, they're both 30 weights at operating temps, but a 5w-30 would tend to shear more. Therefore, in instances where you may actually reach operating temp, a 20 weight or thin 30 weight may produce unfavorable results (like in the summer, maybe?).
Wal-Mart has M1 5W-40 in 5 qt jugs for 19.99, and Rotella T 5W-40 for something like $13/gallon.quote:
Originally posted by MarkC:
I'd like to give that a try, but I can't find any 5W-40 oil around here for less than $4.99 a quart.
That stuff works well in my 4.5L Lexus in-line 6 as wellquote:
Originally posted by HerkyJim:
SuperTech 10-30 is the uniquely, absolutely, end-of-discussion best oil for this engine; period.
My $0.02
I've been running the MaxLife Synthetic in my LX-450 for the past 6 months or so (since I scored 150 quarts at $2/ea at AutoZone). It has a lot of Moly (about 200ppm) and some esters, too. Hard to beat for $2.quote:
Originally posted by Tones:
Another oil you might consider which I am becoming more and more interested in is the Valvoline Maxlife Synthetic 5W-30. If I remember right it is a group III/PAO blend. It may be a little cheaper than the GC.
...but that would involve driving either to Renton or Lynnwood, then spending an hour in the chaotic environment of Wal-Mart.quote:
Originally posted by Palut:
Wal-Mart has M1 5W-40 in 5 qt jugs for 19.99, and Rotella T 5W-40 for something like $13/gallon.quote:
Originally posted by MarkC:
I'd like to give that a try, but I can't find any 5W-40 oil around here for less than $4.99 a quart.