Engine/Transmission (1998.5 - 2002) Oil Change intervals

[GFreshour]

My 01 says oil change at 3500 miles for living in the desert. This is with API CH-4 Oil. With the new CI-4 oil, which is supposed to be more heat tolerant should I go to 7500 miles between oil changes

 

[AKAMAC]

Remember that temp. is relative. Your truck runs at 190, you will only see high of 115~120 on a bad day. The concern is silica deposits from the environment getting into your oil. Try testing the oil at your regular advised change interval and doing a change when the #'s come back showing degradation. I run the 7500 using dino. Your testing will give you a benchmark for future changes. Remember to change the air filter often and avoid the K&N in your area. Yes, I run one. Mike

 

[TomGolden]

I have been running Amsoil in my rig for the last 55K miles or so, with just the single, full flow filter. I have also done oil samples every single oil and/or filter change since day one. I have been changing filters every 5K miles and oil at 10K mile intervals. So far, no problems reported by Blackstone Labs oil analysis.