What’s the Best Oil for a 5.9 Cummins?

Definitely! In winter, thinner oil like 5W-40 can help with cold starts. Just make sure it meets the recommended specs for your truck.

That’s good to know! I often worry about those early mornings when it’s freezing out.

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I also change mine every 5,000 miles when hauling. Keeping the engine clean is key for performance!

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Can’t stress enough how important that is! Dirty oil can lead to serious engine issues.

Sometimes I think it’s easy to forget oil changes! Who else has run into trouble because of it? Mine once turned into a messy affair!

LOL, I can relate! I almost learned the hard way. Now, I set reminders!

I think it’s prudent to follow the manual’s recommendations for intervals and keep an eye on the oil level too.

Exactly! Regular checks are a must. A little effort goes a long way in keeping this beast running smoothly.

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I’ve been using Rotella T6 for my 5.9 Cummins, and I’ve noticed a significant improvement in cold starts and overall smoothness. The engine feels more responsive too!

That’s great to hear, Nelson! I’ve also been a fan of Rotella T6. It really helped my fuel economy, especially during highway driving. How long have you been using it?

I switched to Mobile 1 Diesel 5W-40 about a year ago. While it costs a bit more, the engine wear is less noticeable, and I’ve been impressed with how well it handles high temps during the summer.

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Interesting! I’ve heard good things about Mobile 1 but wasn’t sure it was worth the extra cost. Any noticeable improvements in noise levels?

Honestly, I’m still trying to figure out if there are real differences. I used Valvoline for a while, and it worked fine, but I didn’t feel a huge difference compared to Rotella.

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I’ve been a Valvoline guy for years. It’s never done me wrong, and I’ve had minimal engine wear and good performance. Plus, it’s reasonably priced!

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That’s reassuring to read, Jeffrey! It’s nice to have a reliable option. Did you notice any differences in fuel economy compared to other oils?

Honestly, no big changes in fuel economy for me. But I did run a comparison and found better engine temperatures with Valvoline, which is a plus.

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I’ve been curious about Royal Purple. People rave about it, but is it really worth the hype and cost? Anyone tried it?

I tried Royal Purple once. It was a fun experiment, but honestly, I didn’t feel like it made a huge difference. The truck ran fine, but I think the price was hard to justify for me.

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I have to say, I prefer sticking with more mainstream options like Rotella or Mobile 1. They just feel safer for my engine, you know? Anyone agree?

I appreciate everyone’s input! Sometimes I feel overwhelmed by the choices. I think I’ll stick to Rotella and see how it goes. It seems to have the best reviews overall.