What Oil To Use in My 6.0 Denali

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bayareadude84

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Find a reasonably priced 5w-30 Dexos oil. If the label has Dexos on it, then it meets the OEM requirements. It's kind of a scam from what I've learned about oil ratings, but it DOES mean that it has met certain criteria for that motor.

Or, like stated above, go with a known premium oil and stick with that. A lot of premium oils that don't say DEXOS APPROVED, meet the criteria or exceed the criteria for a 5w-30 synthetic.

I've personally used a good off brand made for fleet use by RELADYNE and it has been stellar for MANY oil changes. Plus it's reasonably priced because the sticker doesn't have any big name on it.

His is a 2006 and it DOES NOT require Dexos !! Dexos is for 2011 and newer GM Vehicles

I was taught this at GM service dept I worked at few years ago and this story in cars.com backs it up

 

bayareadude84

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How do you guys feel about changing oil, but not the filter? I currently have a Fram Ultra Synthetic oil filter which I’ve read is one of the best you can buy and is designed to run up to 20k before changing (not that I’d ever run it that long).

Yes it's one of the most TOP RATED filters out there !! I run the XG3675 on my 01 burb with 2-3 4000K OCI's on it. I would NEVER run ANY filter pass 10K miles !! IMO a $10 filter is not worth passing "trash" into your $$$ engine !!
 

bayareadude84

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To be more accurte, Idles at about 35-38. Giving it the gas barely gets to 40. Which makes me hopefully think it's a weak sending unit. I'll switch the sending unit and if I don't see an improvement, I'll dump the oil and go to Rotella like I had wanted before......:mad3:

If you havent done your oil pick up tube seal Fel-pro # 72401 I HIGHLY recommend it !! Cost under $3 right now on Amazon and you have to drop oil pan and pickup tube to replace it. But better do it now then when it fails and take out your oil pump !!

My 2001 with 200K mile was HARD like a rock and broke into pieces when my mechanic replaced it a few months ago when I first bought it and was doing all PM's on it !! YIKES I dodged a bullet on that one !!

VERY common issue with these vehicle !!


Dave
 

pa31p

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This is one of those threads that will give gravitational pull to just about any forum.

oil when it’s on sale and do it yourself you can do a full synthetic change for about $40 including the filter on your truck. buy something that meets spec.

just about any synthetic of the correct weight for your car will do.

These cars are pretty forgiving to the oil as there’s no turbocharger in it.

You can spend a lifetime reading opinions about what oil is good or bad but hard to go wrong if you stick with the correct weight.
 

bayareadude84

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This is one of those threads that will give gravitational pull to just about any forum.

oil when it’s on sale and do it yourself you can do a full synthetic change for about $40 including the filter on your truck. buy something that meets spec.

just about any synthetic of the correct weight for your car will do.

These cars are pretty forgiving to the oil as there’s no turbocharger in it.

You can spend a lifetime reading opinions about what oil is good or bad but hard to go wrong if you stick with the correct weight.

Welllllllllllllll I tested now discontinued Rotella Gas/truck fully syn (I had 200 qts of the stuff from clearance sales) on my crown vic police interceptor and my 01 burb and I never in my life heard so much engine clatter after 1000 miles or so !! So I quickly flushed out changed that crap oil on both cars. Now the crown vic is running M1 and Suburban running Castrol GTX magnatec and NO MORE clatter and both have super smooth startup !! There's a guy on youtube who is a Ford MASTER tech and he had same horrible results with Rotella in his grand marquis
 

MassHoe04

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I usually run whatever is recommended in the manual by the manufacturer, unless there is some specific reason to do otherwise.

So for as long as my 04 valves and lifters are happy, I'll keep using 5W30 synthetic (Pennzoil, M1, Castrol... whatever is on sale).

If the engine is good on that, I'll stick with it.

In my 05 Jeep, I ran conventional oils. I was changing every 3k miles on that.

While I had intentions of doing every 3k on the Tahoe, I have been going longer. So I'll stick with synthetics on that.
 

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