oil Viscosity for hot wether.

[Abdu1aziz]

My father have 2012 yukon 5.3L and GMC recommending 5W30 dexos grade for their engine. however, he used to change it to this viscosity until the engine started to get older (after maybe 5 years) he changed to 10W30 until today. After 13 years and 270000km (167000mi) the engine valve lifter started knocking. I took the vehicle and changed the 16 valve lifters. Now I think of changing the oil viscosity from 10W30 to 5W40 full synthetic because the oil pressure started to get lower when the engine is hot >150kpa(>20psi) but normal <275kpa(<40psi) in cold-start. (notice that I live in a very hot country 45degrees -50degrees (113F - 122F) on normal days).

should I change to 5W40 or more thicker oil like 10W40 or 20W50 considering my wether?
or I should stick with the 10W30
or should I go back to the original viscosity 5W30?

 

[j91z28d1]

the lifters are a known common problem with these engines. his oil choice definitely didn't cause it and getting 167k miles out of it is very good.

opinions differ on what oil you should run. some always stick with the oem 5w30 others like to change it up. my personality for your Temps, I'd run the 10w40. if you happen to tow heavy loads with it, especially up and down hills in that kinda heat, that 20w50 would definitely not hurt anything.

 

[Marky Dissod]

My father have 2012 yukon 5.3L and GMC recommending 5W30 dexos grade for their engine.
however, he used to change it to this viscosity until the engine started to get older (after maybe 5 years) he changed to 10W30 until today.
After 13 years and 270000km (167000mi) the engine valve lifter started knocking. I took the vehicle and changed the 16 valve lifters.
Now I think of changing the oil viscosity from 10W30 to 5W40 full synthetic,
because the oil pressure started to get lower when the engine is hot >150kpa(>20psi) but normal <275kpa(<40psi) in cold-start.

Note that I live in a very hot country 45C -50C / 113F - 122F on normal days.

should I change to 5W40 or more thicker oil like 10W40 or 20W50 considering my weather?
or I should stick with the 10W30? or should I go back to the original viscosity 5W30?

When it's COLD, 5W40, which should also be fine for colder spring & fall weather.
When it's HOT, 10W40. I would not go as far as 20W50 / 15W40.

The more often you change your oil, the better.
The worse your MpGs, the harder your powertrain works / plays,
the more often you should change your oil.

Goes without saying that these must all be Group3 or Group4 synthetics, nothing less.

 

[Z15]

The W in 10W-40 muliti-viscosity motor oil stands for Winter and indicates the oil meets or exceeds certain criteria for good low-temperature performance. Motor oil with SAE viscosity grade 10W-40 behaves like an SAE 40 oil at high temperatures and SAE 10W oil at low temperatures, providing the necessary fluidity for rapid starts and efficient engine operation at low temperatures.

An oils cold-temperature performance refers to its ability to flow when the engine is cold, or below typical operating temperature (212 F / 100 C), and not simply to what feels cold to humans - warm summer days are also cold to an engine. Startup lubrication is directly affected by a lubricants cold-flow ability, and the impact is felt at higher temperatures than most consumers would think.


Higher viscosity = slower flow
Low viscosity = faster flow

 

[Abdu1aziz]

the lifters are a known common problem with these engines. his oil choice definitely didn't cause it and getting 167k miles out of it is very good.

opinions differ on what oil you should run. some always stick with the oem 5w30 others like to change it up. my personality for your Temps, I'd run the 10w40. if you happen to tow heavy loads with it, especially up and down hills in that kinda heat, that 20w50 would definitely not hurt anything.

Maybe I’ll try the 10W40 synthetic for couple months and see if it goes great for the vehicle.
If not I’ll stick back to 10W30

 

[rdezs]

Since you live where the temperatures are routinely are in excess of 100° in the summer, I would definitely run the 10w40 full synthetic.

 

[Foggy]

I run 5w40 full synthetic in the warmer months. I still get the cold start
properties of the 5W and a little hot benefit with the 40W
In the early fall I switch back to 5w30
BTW your engine calls for Synthetic Oil Only... So make sure you are using that

 

[rdezs]

I think we need to focus on what he described as average daily temperatures of 113 F to 122 F on normal days. (Central Saudi Arabia?) That would mean the low temperatures are in the 80F range at night if he lives near Riyadh. I think the Mobile One 10W-40 synthetic would be the way to go.

 

[Marky Dissod]

I think we need to focus on what he described as average daily temperatures of 113F to 122F on normal days.
(Central Saudi Arabia?) That would mean the low temperatures are in the 80F range at night if he lives near Riyadh.
I think the Mobil1 10W40 synthetic would be the way to go.

Mobil1's 40-weight oils get thin enough to no longer qualify as 40-weight after as little as 1000 miles.
I tend to prefer other synthetics such as Pennzoil, Quaker State, or Valvoline.
(Stopped using Castrol once they stopped making their 'grun ol'.)

 

[rdezs]

Lol ... Valvoline has always been my personal preference

 

[Marky Dissod]

Valvoline has always been my personal preference.

Mine too, and that was BEFORE Restore & Protect.
Now people think I work for Valvoline ... PAY ME, MOTHAPHUCCAZ.

 

[Z15]

Lol ... Valvoline has always been my personal preference

Saudi Arabia thanks you for your support!