How often do you do your oil changes?
Post Fiend
Joined: Dec 2002
Posts: 6,245
Likes: 1
From: IL, USA
With Valvoline Premium Blue 15W-40 I go 3000miles.
With the Valvoline Premium Blue Extreme 5W-40 Synthetic I go 5000 miles.
Back when I used Rotella 15W-40 I'd go 3000 miles. My trucks (9 Super Duty PSDs) didn't like the oil, run and start better with the Valvoline so that's what I stick with.
With the Valvoline Premium Blue Extreme 5W-40 Synthetic I go 5000 miles.
Back when I used Rotella 15W-40 I'd go 3000 miles. My trucks (9 Super Duty PSDs) didn't like the oil, run and start better with the Valvoline so that's what I stick with.
Post Fiend
Joined: Sep 2006
Posts: 6,634
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From: bricktown NJ
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Hotshot
Joined: Aug 2006
Posts: 17,400
Likes: 319
From: Whittier, CA
Wow! I guess you are using analysis to find the end of life on the oil. Can you elaborate a little on that? Did you change it at 18k, or are you still looking for the EOL?
Them is some big brass cajones you got there Marv!
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Brett Foote
Elder User
Joined: Jan 2004
Posts: 853
Likes: 0
From: northern,california
I just changed my oil this weekend. Had 6500 miles on her. This is the longest I have gone. I usually go around 5-6 K. I also send oil to Blackstone for a report. They keep telling me to I can go longer on the oil. Delo 15/40 cj4.
Hotshot
Joined: Jan 2002
Posts: 17,988
Likes: 207
From: La La Land
During the 18,000 mile oil life, I change bypass filters at 5,000, 10,000, and 15,000 miles. I send samples in at 6,000, 12,000, and 18,000 when it gets dumped. So long as my Blackstones come back as good as they do, I'm not going to change my intervals. "If it ain't broke, don't fix it!"
I could go longer, but like you all, I have my "set point". Mine is just a bit higher than some.
If anyone would like to see my last few reports, PM me with your email address and I'll forward the latest PDF for your review. It has the last few samples on it as a running history.
18,000 is where it tends to begin dipping in viscosity, so that's the decision-maker. It would still be good-to-go in something that uses a 30+ weight oil.
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