Originally Posted By: Blackhatch
What are optimum oil temps for a 0w-40 full synthetic.
I didn't beat on this truck that hard at all and I was seeing temps just north of 250 pretty easy.
Just cruising it stays near the 230-250 mark and we have pretty cool temps right now.
Thanks.
TOTALLY normal for the 6.4/392, and doesn't hurt the oil whatsoever. In fact, the oil "cooler" acts as an oil heater during warm-up to get the oil up to temp faster. You shouldn't start pushing it until the temp is over 160, and Chrysler engineers say they aim for a *minimum* oil temp of 190 on the Pentastar v6 so I assume they Hemis are similar, or a little higher in the case of the 392 spec'd for 0w40 oil. My 392 runs about 220 cruising the toll road at a steady 80 mph, will run up over 230 if I play with it some. How many miles on yours? Mine always ran at 230+ until it reached about 10k-12k miles, and then I started seeing the average cruising temp decrease until its now typically 215-220 in normal driving, (220 at sustained 80 mph).