Question about best oil for timing chain rattle at startup on 06 Colorado 2.8L (Atlas engine)

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Oct 11, 2022
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My 2006 Colorado has timing chain rattle at startup for just a few seconds then it's fine. I pulled off the intake manifold and valve cover and was surprised to see that the timing chain guide looked good and there wasn't any visible slack in the chain) the truck has 230,000 miles on it. I asked the person I bought it from and he said he had the timing kit installed at 180,000 miles and it has made the noise at startup every since. He said he was told that it takes a few seconds for the oil to get to the hydraulic tensioner. I had been using the same brand and # of oil filter he had used with it and upon looking into it, that filter doesn't have an anti-drainback valve so I switched to a Fram Toughguard filter this time, but I am changing the oil anyways and am wondering if heavier or thinner oil would help the tensioner get enough oil at startup to eliminate or at least reduce the rattle. I asked a few local mechanics and one said switch to synthetic 0w40, another told me 20w50. I figured I would get a better answer on here. I was thinking Mobil 1 synthetic since I can't get amsoil near where I live unless someone else has a recommendation of a better brand. The weight is my main question though. The truck has had 5w30 in it up until now.

Thanks in advance.
 
When it comes to cam rattle at start up the go to option was castrol gtx magnatec 30 grade but it seems to have been replaced with gtx full synthetic silver bottle. Some swear that it helps but for the most part a euro 40 grade will be fine, not too thick or thin. That 20w-50 might be sluggish if it gets cold where you live. Some say to prime the engine by doing a flood mode start to not have the start up rattle but that doesn't help much. But the fact that it didn't start making that noise until after it was worked on is concerning.
 
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When it comes to cam rattle at start up the go to option was castrol gtx magnatec 30 grade but it seems to have been replaced with gtx full synthetic silver bottle it seems and some swear that it helps but for the most part a euro 40 grade will be fine. Not too thick or thin. That 20w-50 might be sluggish if it gets cold where you live. Some say to prime the engine by doing a flood mode start to not have the start up rattle but that doesn't help much. But the fact that it didn't start making that noise until after it was worked on is concerning.
Thanks for the reply. I guess I should have clarified, it made the noise before the previous owner had it worked on, it just had the rattle all of the time. After the timing kit was installed it only had the rattle when first started. So I should get Castol GTX full synthetic? You mentioned 30 or 40 grade, but what about the 1st #? Should I get 5w/30 or 40 or 10w30 or 40?
 
Thanks for the reply. I guess I should have clarified, it made the noise before the previous owner had it worked on, it just had the rattle all of the time. After the timing kit was installed it only had the rattle when first started. So I should get Castol GTX full synthetic? You mentioned 30 or 40 grade, but what about the 1st #? Should I get 5w/30 or 40 or 10w30 or 40?
On here it's generally better to have a higher W since that means that the oil will usually perform better in regards to resisting viscosity and hths loss by having less VII or viscosity improvers/polymers or sometimes just called plastic crap. There are only a handful of oils that are better in the lower W form since the base oils are much better than that of the higher w rated version of it but not always. But for standard group 2 and 3 based oils most gravitate towards a higher w rating, I've seen valvoline pds's showing that the higher w rated version had a slightly higher hths while being a little less thick at the same time. But euro and diesel oils tend to be better formulated compared to just regular gas oils so i use both in my trucks with their age, use, and mileage.
 
On here it's generally better to have a higher W since that means that the oil will usually perform better in regards to resisting viscosity and hths loss by having less VII or viscosity improvers/polymers or sometimes just called plastic crap. There are only a handful of oils that are better in the lower W form since the base oils are much better than that of the higher w rated version of it but not always. But for standard group 2 and 3 based oils most gravitate towards a higher w rating, I've seen valvoline pds's showing that the higher w rated version had a slightly higher hths while being a little less thick at the same time. But euro and diesel oils tend to be better formulated compared to just regular gas oils so i use both in my trucks with their age, use, and mileage.
 
Thanks, so if it was your vehicle and had this issue, and you lived in a place where the climate is avg 80-90 in the summer and gets down below 0 in the winter what weight would you run? Like 10W40 perhaps?
 
As Javier said Castrol Magnatec should do the trick if it was still made. I used Mobil 1 5W-30 in my 2017 GMC Canyon 3.6 V6 and it had a start up rattle. I attributed my rattle to the cam phasers but it could have been the tensioner. Once I switched to 5W-30 Magnatec it stopped. Since it was discontinued I now use Havoline Pro DS (now called Lifelong) 5W-30 and there is no start up rattle. The Magnatec had titanium but the replacement GTX does not from what I have read. Try the Havoline or the Castrol Edge (the Edge still has titanium.)
 
Thanks, so if it was your vehicle and had this issue, and you lived in a place where the climate is avg 80-90 in the summer and gets down below 0 in the winter what weight would you run? Like 10W40 perhaps?
Gets down below zero. I'd use Castrol 0w-40 or m1 0w-40. The 5w-40 versions are good too especially quaker state euro 5w-40 for its value proposition. But if It's below zero I'd make it a bit easier on the engine for oil to get to that phaser by having a 0w oil instead of 5 which is just a bit thinner but it's a well formulated oil. Where I live it almost never goes below 30f. Usually 35 or so during peak cold.
 
Thank you both for the great information. I will try some Havonline Lifelong 0W40 and see how it goes.
thanks again!
 
Gets down below zero. I'd use Castrol 0w-40 or m1 0w-40. The 5w-40 versions are good to especially quaker state euro 5w-40 for its value proposition. But if It's below zero I'd make it a bit easier on the engine for oil to get to that phaser by having a 0w oil instead of 5 which is just a bit thinner but it's a well formulated oil. Where I live it almost never goes below 30f. Usually 35 or so during peak cold.
Depending on how close to 0F you’re talking there is no guarantee that a same-grade oil with a 0W winter rating will be thinner than one with a 5W rating. In fact it may be thicker. Not until you are below about -30 is that guaranteed.
 
So do you think I would be better off with 5w40 than 0w40?
Also it's looks like Havoline isn't available where I am, just Mobile 1 for European vehicles,Shell Rotella, and Royal Purple. any preference between any of those 3?
 
Any 0w40 is a good start or even a 3.5+ hths euro 0w30

Use a synthetic oil filter.... should be able to find or order a Napa Platinum, Wix XP, or Purolator Boss at some of your local autopart stores.

If you want to test the engine's internal filter bypass, which could be varnished up and not fully opening, use a Harley Vrod oil filter.
 
Just tossing this in there…quietest oil I’ve had in my 2.2 Ecotec with a light timing chain rattle is PP 5W-30.
 
I can't see how any oil is going to stop chain noise. I guess if you're in that period where all the oil may or may not have drained out of the tensioner by the time you crank it again, a thicker oil may drain out slower.

You almost certainly have a leaky tensioner. Perhaps the "timing kit" didn't come with new tensioners, or it's got a bad tensioner out of the box.
 
I have observed when oil is half way the normal range on dipstick I have quiet startup on the Nissan. Definitely more clattery when oil on H mark.
 
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