Oil weight is based on the climate you live in ,, I’m not sure if changing it is going to do anything for the temps ,, I run the 15 50 and oil consumption went down ... that was after trying several different oils ,, 0 40 Mobil one ,,, royal purple 0 40 and the 15 50 .. I live in Florida hot climate ,,, you live in Texas hot climate . You’ve been using the 15 50 and have 168k miles on the truck .. something to be said for that considering I think you stated on another thread you have low oil consumption!
The 0 is for colder climate and the 40 is for hotter climate .. I believe the 40 is sufficient for your climate and mine but the 0 is not needed there .... multi viscosity covers climate temperature ranges ... so 15 would be more than fine and 50 covers the hottest climate days ... up north in the cold would be different ..
Too much misinformation here in this reply. The good news is that you retained your grill block off panels. VERY HUGE in many aspects of performance!! Oil weight however, is determined by the OEM based off engine clearances and DESIGNED oil FLOW for the engine. If your "package" is as you state, you have ALOT to gain. The original oil specified for these V10 engines was 10W30. Then, due to improvements in oil technology, went to 0W40 in 2005.
Any engine will benefit from a decent synthetic and will run for many miles without much issue related to oiling. However, the M1 15W50 you both are running is too high in viscosity and WAY down on the wear protection list. It is #188
I urge you both to read this BLOG (
https://540ratblog.wordpress.com/2013/06/20/motor-oil-wear-test-ranking/ ) and pick up some facts. Here is a snip-it from the blog that relates to this topic of engine heat....
>>> "• Oil flow is what carries heat away from internal engine components. Those engine components are DIRECTLY oil cooled, but only IN-directly water cooled. And better flowing thinner oil will keep critical engine components cooler because it carries heat away faster than slower flowing thicker oil can. This is especially important with plain main and rod bearings, since the flow of oil through the bearings is what cools them. If you run thicker oil than needed, you will drive up engine component temps.
Here are some comparison numbers from an 830 HP road race engine on the track:
15W50 oil = 80 psi = 265* oil sump temperature
5W20 oil = 65 psi = 240* oil sump temperature
Here you can see how the thicker oil flowed more slowly through the bearings, thus getting hotter, driving up bearing temperatures and increasing sump temperatures. And the thinner oil flowed more freely and quickly through the bearings, thus cooling and lubricating them better than thicker oil, while also reducing sump temperatures."
• Thicker oils DO NOT automatically provide better wear protection than thinner oils, as some people mistakenly believe. Extensive “dynamic wear testing under load” of approximately 200 motor oils, has shown that the base oil and its additive package “as a whole”, with the primary emphasis on the additive package, which is what contains the extreme pressure anti-wear components, is what determines an oil’s wear protection capability, NOT its viscosity. In fact, the test data has shown that 5W20 oils can provide INCREDIBLE wear protection with over 120,000 psi load carrying capability/film strength/shear resistance, while 15W50 oils can sometimes only provide UNDESIRABLE wear protection with less than 60,000 psi. So, DO NOT use thicker oil under the assumption that it can provide better wear protection for our engines, because that is simply NOT TRUE." <<<
Just some serious things to consider...It's not that I think you're dumb, it's just that so much of what you know isn't true....
Cheers!!