Who uses 5w20 and who uses 5w30 oil?

petbug · Apr 9, 2009

Mobil 1 5-20 synthetic

homac · Apr 10, 2009

Not correct.....

You will not get quicker lubrication on start-up with 5W-20. Both 5W-20 and 5W30 are 5W when cold.

You are correct about the manual and oil cap, however the reason for that is the issue. Chrysler agreed to 'recommend' 5W-20 so they could use the very slight improvement in fuel economy to hit the US Government CAFE targets. All things being equal 5W-30 will protect the motor slightly better and provide better fuel economy in the long run. (Especially if you opt for a synthetic)

Do a search here, on Google and visit 'Bob is the Oil Guy' for more information.

Casse said:
Hi. Said it before in another thread, and I'll say it again: The manual for USA 'Riots says 5w20; the oil filler cap says 5w20, why run a heavier oil? How does that make sense for better lubrication, quicker lubrication on start-up, and better flow rate through the oil ports and returns? Higher MPG with 5w30 is just confounding, because driving conditions, style, load, time of year, everything, would have to be exactly the same to test that theory. I can maybe understand a heavier oil if your 'Riot is running around in the desert SW in July, or 0W10 for the Yukon in January, but I haven't seen any info on that. Maybe the most important questions are: Oil change interval; oil filter quality; dino, blend, or synthetic oil. [PS I know the 'Riots made for Europe require 5W30, but don't know what the reason is... maybe 'cus they are diesel.] The beat goes on. PS. I use Castrol Syntec 5w20.

UA_who · Apr 10, 2009

Reasons for using 5W-30 instead of 5W-20:

Reason #1

Casse said:
... understand a heavier oil if your 'Riot is running around in the desert SW in July...

Reason #2

Casse said:
...PS I know the 'Riots made for Europe require 5W30, but don't know what the reason is...

Reason #3

Homac said:
Chrysler agreed to 'recommend' 5W-20 so they could use the very slight improvement in fuel economy to hit the US Government CAFE targets... 5W-30 will protect the motor slightly better...

Reason #4
Synthetic 5W-30 seems to be easier to find around Phoenix here than the Synthetic 5W-20. (probably related to Reason #1)

Kostantinos Porto Rafti · Apr 10, 2009

In hot weather and dusty atmosphere like in Greece only the 5-30 synthetic will stand the demands.

Wooden Dog · Apr 10, 2009

homac said:
Not correct.....

You will not get quicker lubrication on start-up with 5W-20. Both 5W-20 and 5W30 are 5W when cold.

You are correct about the manual and oil cap, however the reason for that is the issue. Chrysler agreed to 'recommend' 5W-20 so they could use the very slight improvement in fuel economy to hit the US Government CAFE targets. All things being equal 5W-30 will protect the motor slightly better and provide better fuel economy in the long run. (Especially if you opt for a synthetic)

Do a search here, on Google and visit 'Bob is the Oil Guy' for more information.

It should be understood, however, that the "5" doesn't indicate a set value, but rather a range of values, therefore, a 5w20 may very well flow better at low temps than a 5w30(of the same brand, of course.).

homac · Apr 10, 2009

Wooden Dog, this is not accurate.

"5" does indicate a set value (at least when the oil is new). 5W is the vicosity of the oil at −30 °C (−22 °F).

The second # (20 or 30 in this case) is at operating temperature. 150 °C (300 °F)

You will see no viscosity difference between 5w-20 and 5w-30 until at least 75 °C.

Wooden Dog said:
It should be understood, however, that the "5" doesn't indicate a set value, but rather a range of values, therefore, a 5w20 may very well flow better at low temps than a 5w30(of the same brand, of course.).

timeburgler · Apr 10, 2009

Here is some damning reasons to not use 5W-20. These have been well circulated on the forum:

Jeep Patriot 5w-30 TSB

Mobil 1 Jeep Patriot Recommendation (5w-30)

Letter from Chrysler advising 5w-30 can be used

EPA Letter regarding 5w-20 (explains what car makers need to do so 5w-20 can be used to help them hit their EPA CAFE targets)

Hitzy · Apr 11, 2009

Wooden Dog said:
It should be understood, however, that the "5" doesn't indicate a set value, but rather a range of values, therefore, a 5w20 may very well flow better at low temps than a 5w30(of the same brand, of course.).

Mobil 1 5w30 has a lower pour point then Mobil 1 5w20.....not much though.

Wooden Dog · Apr 11, 2009

I did misspeak.
I wonder how Chrysler will handle the lifetime warranty if 5w30 is used?

homac · Apr 11, 2009

The links in a previous post show you would not have any warranty problems.

Wooden Dog said:
I did misspeak.
I wonder how Chrysler will handle the lifetime warranty if 5w30 is used?

Roadstar-Patriot · Apr 11, 2009

I use 5-30 synthetic in my "Riot" and I use 20-50 in my motorcycle...
I hit the rev limiter once in a great while in the Riot, (I thinks it's set around 6300 RPM...) But, the bike sees the rev limiter almost once every trip! (It's set at the factory at 5200 RPM.) The bike is a 1.7 liter "V" twin and as y'all know the Riot is an in line 4...
Both machines are used in south Florida (USA) and I'm lucky to see temperatures in the mid seventies once in a while... Typically like last nights ride home... It was 85 degrees and I was traveling 85 MPH for nearly an hour...
Under those conditions, my Riot needs all the protection it can get...!:Racing:

Wooden Dog · Apr 13, 2009

timeburgler said:
Here is some damning reasons to not use 5W-20. These have been well circulated on the forum:

Jeep Patriot 5w-30 TSB

Mobil 1 Jeep Patriot Recommendation (5w-30)

Letter from Chrysler advising 5w-30 can be used

EPA Letter regarding 5w-20 (explains what car makers need to do so 5w-20 can be used to help them hit their EPA CAFE targets)

As far as the Mobil 1 recommendation, when I use the Mobil 1 website, it recommends 5w20, as does the Castrol website.

Hitzy · Apr 13, 2009

I used Mobile 1 5w20 for the first time this winter, I had been using M1 5w30. I wasn't going to be towing anything, so I figured I'd try it to compare.
Didn't really notice any difference driving, but when I changed it at 5000km, it came out very black. The 5w30 never looked that black after 5000km.

SteelPepe · Apr 24, 2009

i put 10w30 Acdelco synthetic oil.... happy with it no problems so far, it has 3,000 km´s running with it.

wpeck2 · Apr 25, 2009

I use regular 5w20 in the Winter and 5w30 in the Summer. I highly recommend a good quality filter and check oil for discoloration (contamination) at 3000 mi.

timeburgler · Apr 26, 2009

Like many have found I also had issues with several types of 5w20 oil. (dirty oil after only 1000 miles and engine seems to run a bit loud)

I started using Mobil 1 5w30 and things are much better now. Oddly the fuel was a bit better too.

SilverSlimer · Aug 20, 2010

I just put in Mobil 1 5w20 synthetic at 3200km. It's amazing how quickly the changes are apparent. The engine is a not as noisy and it doesn't seem to struggle as much with the acceleration when I keep the engine under 3000rpm. I'm never going back to regular again.

todde702 · Aug 20, 2010

timeburgler said:
Here is some damning reasons to not use 5W-20. These have been well circulated on the forum:

Jeep Patriot 5w-30 TSB

Mobil 1 Jeep Patriot Recommendation (5w-30)

Letter from Chrysler advising 5w-30 can be used

EPA Letter regarding 5w-20 (explains what car makers need to do so 5w-20 can be used to help them hit their EPA CAFE targets)

Add one more link to this:
http://www.machinerylubrication.com/Read/518/motor-oils

Specifically (and I believe this is why our engines run at a fairly cool 180 deg. F, because of the 5W20, and also why Jeep requires an oil cooler for the 2000 lb tow rating):

Any abrasive particles equal to or larger than the oil film thickness will cause wear. Filters are necessary to keep contaminants small. The other side of the equation is oil film thickness. Thicker oil films can accommodate larger contaminants.

Temperature has a big effect on viscosity and film thickness. As a point of reference, one SAE grade increase in viscosity is necessary to overcome the influence of a 20°F increase in engine temperature. At a given reference point, there is approximately a 20°F. difference between viscosity grades SAE 30, 40 and 50. SAE 20 is somewhat closer to 30 than the other jumps, because SAE 30 must be 30°F higher than SAE 20 to be roughly the equivalent viscosity.

In other words, an SAE 20 at 190°F is about the same kinematic viscosity as an SAE 30 at 220°F, which is about the same viscosity as an SAE 40 at 240°F. This approximation works well in the 190°F to 260°F temperature range. One might be surprised at the slight amount of difference between straight viscosity vs. multiviscosity oils with the same back number (for example, SAE 30, SAE 5W-30, and SAE 10W-30).

If an SAE 50 oil at 260°F is as thin as an SAE 20 oil at 190°F, imagine how thin the oil film becomes when you are using an SAE 5W-20 and your engine overheats. When an engine overheats, the oil film becomes dangerously thin and can rupture.

Wooden Dog · Aug 20, 2010

But where are the thousands of vehicles with damaged or prematurely worn-out engines from using 5W20?

todde702 · Aug 20, 2010

Probably right next to the damaged, over stressed engines from running 5w-30.

Hey, I'm just passing on some basic lubrication/viscosity/temperature science. Thinner oil = thinner film. So long as the engine doesn't severely over heat, and/or you don't get any particles larger then the oil film then all is good.

Who uses 5w20 and who uses 5w30 oil?

5w20 or 5w30?

5w20 Conventional

5w20 Synthetic

5w30 Conventional

5w30 Synthetic

petbug

homac

UA_who

Kostantinos Porto Rafti

Wooden Dog

homac

timeburgler

Hitzy

Wooden Dog

homac

Roadstar-Patriot

Wooden Dog

Hitzy

SteelPepe

wpeck2

timeburgler

SilverSlimer

todde702

Wooden Dog

todde702

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