I own a 2014 Grand cherokee V6. Recommended oil is 5w-20. As I live in the tropics where ambient temp. is between 20-40 degrees celcius all year round. Can I change the oil grade to 5w-30 or 10w-30. It seems to me that I can even use single grade 30. Can somebody comment?
Changing recommended oil grade
- Thread starter Tjulo
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I'd use 5W-30. Straight 30 is really thick when cold, and provides no benefit over multigrade.
I live in South FL and in many of my vehicles I step up a viscosity grade or two, including my Supercharged Jag F-Type (0-20 to 5-30) But before I do that, I always do my research. The Ford 5.4L 3V engine in my previous truck also spec'd a really thin oil. One that was not used a year earlier in the same engine. It came as no surprise to those of us who did the research that the Ford dealer was overwhelmed with warranty repairs. The dealership fix was to switch from 5W-20 to 10W-40 full synthetic. This had a 100% cure rate.
My current 5.0 V8 powered F150 requires 5W-30. These engines have no known failure modes and last forever with even average care. I will not be changing the oil viscosity unless I learn something in the future. Plenty of these engines out there with 300-400K, no oil related probs.
The 3.6 quickly turned into a very reliable engine and the owners manuals of many different applications spec'd or allowed the use of 5W-30. Also many owners switched to 5W-30 as they were annoyed by follower wear and blamed it on the thinner oil, possibly rightly so.
The switch to a quality 5W-30 is a no risk change in your case. And I'd guess your owners manual allows the use of 5W-30.
My current 5.0 V8 powered F150 requires 5W-30. These engines have no known failure modes and last forever with even average care. I will not be changing the oil viscosity unless I learn something in the future. Plenty of these engines out there with 300-400K, no oil related probs.
The 3.6 quickly turned into a very reliable engine and the owners manuals of many different applications spec'd or allowed the use of 5W-30. Also many owners switched to 5W-30 as they were annoyed by follower wear and blamed it on the thinner oil, possibly rightly so.
The switch to a quality 5W-30 is a no risk change in your case. And I'd guess your owners manual allows the use of 5W-30.
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In a 2014 Jeep, I would say go for it. However always use caution. A friend of mine lost a Triton V-10 after using the wrong oil. Also, many new engines have variable valve timing which is controlled by oil pressure. The good old days of "Pour it in. Oil is oil" are long gone.
Please elaborate on “wrong oil” and how vvt will be adversely affected. I have a Toyota with vvt which specs 0w16 and run a 30w with no issues.
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Please elaborate on "a 30w with no issues." Are your running 0W-30 or non-detergent 30W? I would say that you're probably fine running 0W-30. If it's anything significantly heavier, let us know how that works out after 50,000 miles or so.
0w30 HPL premium plus and 5W30 HPL NO VII. No issues regarding the “concerns” you alluded to about vehicles with variable valve timing. I wouldn’t be scared to run a 40w but it’s just not necessary in this vehicle. So, back to my initial question you deflected from…..
Thick oil has a habit of pushing Toyota VVTI intake phaser lock pins out and not allowing them to re-seat and lock. This causes an awful rattle on a cold start. However, the problem is caused by Toyota using a weak spring which is then exacerbated by thick oil. The resolution is to change the spring to a stronger one.
I asked op about the “wrong oil” in his friends ford v10 he posted about; not about my vehicle or oil usage as I have no concerns. Using a thicker viscosity is not going to cause any issues as long as the winter grade is acceptable for climate.
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My friend had a Triton V-10 in a new motor home. He said "Oil is oil. Dump it in" and we headed down the road on our annual camping trip. About 20 miles later, his new Triton V-10 started knocking and he was stranded along Interstate-5. The cause of failure was oil starvation to bearing #blahblah due to off-spec oil. His warranty claim was denied. His appeal was denied. Lawyer said that he had no case because Ford had evidence and he admitted to using a different oil.
So, good luck with your oil experiment. Again, let us know how that works out after 50,000 miles or so.
So using a 0w30 in a vehicle that specs 0w16 is considered an experiment; interesting concept. Just bc your friend lacks adequate knowledge, pertaining to appropriate oil selection, does not mean I need any luck; but thanks for your concern.
Without knowing what oil was chosen, I'm just going to have to guess. But the Triton 10 cylinder has a known issue with the oil filter adapter gasket blowing out. Starving the engine of oil. This is not related to oil viscosity, but to poor design. Of course, a fresh oil change can increase oil pressure and cause the problem to happen sooner. And/or the use of an oil too thin can 'leak' out of the oil pump backing plate and fail to provide enough oil pressure. In BOTH cases, it is a component flaw.
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Sorry, I don't have any more details. I was just along for the ride. I do know one thing...that new motor cost the guy a lot of money. It was a lesson learned and I'm just sharing what I know.
Bumping one grade won't cause catastrophe. I just don't see any benefit in 10W-30 over 5W-30.
Lower viscosity spread.
Before disseminating any information, please thoroughly research and comprehend the subject matter. It is crucial to avoid spreading misinformation, as it can lead to incorrect beliefs and potential harm. If you firmly believe that using a thicker viscosity is detrimental to an engine, then you are indeed misinformed.
Yeah the multi grade w part doesn't even start to do anything till around 0 to 10c.
At 20c there will be almost no difference between straight 30 vs 5w-30.
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