Using 5w40 instead od 5w30 for better protection?

[gfh77665]

Originally Posted by barryh
It's a shame a relatively new member can't ask an honest question without receiving some sarcastic responses.


I agree. This forum suffers from snark, sarcasam, and "unicorn" type non-answers, especially when aimed at new members seeking sound advice and information.

I also cringe when someone asks: "A or B", and they are told "C,D,E,F, or G..." and anything BUT an "A or B".

 

[OilReport99]

^^^
Most helpful reply, so far.

 

[mclasser]

I used Castrol 5w40 instead of the spec'd 5w30 several times on my old Infiniti. Everything was fine

 

[krismoriah72]

The only major difference between ​5w30 and 5w40 is the viscosity in warmer temperatures.

 

[Bjornviken]

Originally Posted by HangFire
0w100. It's really the final answer to all viscosity questions.

...‚...‚🤣🤣ðŸ‘

 

[CT8]

0W-40 !

 

[Onetor]

I know it's been a few months, but welcome to Bitog! 5W40.

 

[pbm]

Originally Posted by barryh
It's a shame a relatively new member can't ask an honest question without receiving some sarcastic responses.

I think he was asking ; which parts of the engine would benefit from the thicker oil. I suppose the answer is nothing that's hydrodynamically lubricated like the bearings because 5W30 would more than likely provide adequate oil film thickness. That leaves things like timing chains and possibly cams that are boundary lubricated.


I agree....with both parts of your response....

 

[gamefoo21]

I have 5w40 in a relative's 2.4L GM Ecoturd.

5w30 gets eaten far too quickly, once it gets sheared down.

I think it's interesting that most engines will spec heavier oil when they get used harder than putting around town.

I use 5w40 in my high strung 1L 3 banger.

 

[metroplex]

Ford specifies their 5W-50 synthetic for the Mustang 2.3L EcoBoost High Output, and a 0W-40 when it is below -22F. I was surprised to see this in the 2020 Mustang manual, but it is there. This confirms my suspicion that the GTDI engines are very hard on the 5W-30 oils they specify, but in order to meet CAFE I suspect Ford just calls out the 5W-30 synth blend for all "normal" EcoBoost engines but for those that are driving the engines hard, 5W-50 will work better.

 

[gamefoo21]

I've posted before but honest to god this was my experience with the vehicle and my relatives ran it on premium gas because the wife could tell a very noticeable difference between regular and premium just driving around.

Relatives had a 15 Fusion, 2.0 EB 6 spd slushbox with AWD. 270hp/270ftlb with 91 octane, 240hp/270ftlb with 87 octane, according to Ford.

With a full sump of Ford full synthetic 5w30 and a diet of premium aka 91 octane top tier gas... it had almost no fuel dilution issues. It would just crank the boost to go up hills on cruise at 110kph. You could hear the turbo whistle, it was a sweet song. 8.5-7L/100km on the highway.

With a sump full of their semi synthetic, it would start poisoning about half way through.

With a sump left low by Ford techs for room for fuel dilution, it would pull boost, and start poisoning right away.

With regular gas aka 87 octane, it would pull boost, pull timing the fuel economy dropped, and the oil stunk of gas. That hill would now require it to unlock the torque converter, and drop a gear. You never heard the turbo whistle and it was much groggier feeling. 10-10.5L/100km on the highway

If the oil is getting too hot, the computer pulls back to protect the turbo. When it pulls back, it starts pushing more fuel, and pulling timing...

Even modern factory vehicles are bound by the rules...

1) Good boost needs good fuel and oil
2) Thinner oils get hotter, hot oil can't keep up the viscosity to protect parts.
3) Just because it can run on 87 octane, doesn't mean it'll run it's best.
4) Running big boost with lousy gas requires compromises, and those compromises will affect things, such as running incredibly rich, which is why you get fuel dilution issues.
5) Low viscosity oil, and big boost don't get along.

I consider big boost to be more than 7psi with a base engine CR of 9:1.

It's wanted to see if 87 octane would make a measurable difference at highway speeds and I thought watching timing advance on a engine at a fixed speed/load would be telling.

So recently I decided to test just a boring 2L with 9.5:1 CR, just watching the timing advance on cruise bumping down the highway, with a fully warmed engine and as similar a situation I can manage. 115Kph, manual trans in 5th, 3200rpm(iirc) and tires at 35psi.

Timing advance results via OBD2 and Torque Pro with an OBD MX BT adapter:

87 Octane: 28 - 32 degrees, bouncing around a lot
91 Octane: 39 - 40 degrees, rarely moved

The OM of this 16V DOHC VVT engine, says to run it on 87 octane.

Edit: Yes, I realize that my post will likely garner a lot of hate, but eh, it was mine and their experience

 

[Polyalphaolefin]

My apologies. Here are some info about my car:

Engine is naturaly aspirated 1.4 (100hp) port injection made by Hyundai. My driving style is average, mostly city driving, very little highway. On summer temperatures get about 35-39°C (july, august), but on other moths it is average european climate.

Since my car recoomends using low HTHS oil - 5w30 ACEA A5B5, I was htinking to swith to 5w30 ACEA A3B4 (higher HTHS, because I dont care about 1% worse fuel economy, and try to protect engine as much as possible, but also for the same reason I was thinking of using 5w40 at least on summer months).

I have a chance to use PAO based oil 5w40 for the same price of HC oil 5w30 .... so was thinking about that too.

 

[kschachn]

Why make a post and end it with the tired old "hate" statement?

The only questions I would ask is how are you determining fuel dilution in your examples? Were you having the oil tested by a lab that uses gas chromatography?

Also, a thicker oil gets hotter than a thinner one. There are more shear forces in the bearings and this warms a thicker oil up more than one than one which is thinner. It also takes more energy to move a thicker oil, that energy has to go somewhere and it is into the oil.

Originally Posted by gamefoo21
I've posted before but honest to god this was my experience with the vehicle and my relatives ran it on premium gas because the wife could tell a very noticeable difference between regular and premium just driving around.

Relatives had a 15 Fusion, 2.0 EB 6 spd slushbox with AWD. 270hp/270ftlb with 91 octane, 240hp/270ftlb with 87 octane, according to Ford.

With a full sump of Ford full synthetic 5w30 and a diet of premium aka 91 octane top tier gas... it had almost no fuel dilution issues. It would just crank the boost to go up hills on cruise at 110kph. You could hear the turbo whistle, it was a sweet song. 8.5-7L/100km on the highway.

With a sump full of their semi synthetic, it would start poisoning about half way through.

With a sump left low by Ford techs for room for fuel dilution, it would pull boost, and start poisoning right away.

With regular gas aka 87 octane, it would pull boost, pull timing the fuel economy dropped, and the oil stunk of gas. That hill would now require it to unlock the torque converter, and drop a gear. You never heard the turbo whistle and it was much groggier feeling. 10-10.5L/100km on the highway

If the oil is getting too hot, the computer pulls back to protect the turbo. When it pulls back, it starts pushing more fuel, and pulling timing...

Even modern factory vehicles are bound by the rules...

1) Good boost needs good fuel and oil
2) Thinner oils get hotter, hot oil can't keep up the viscosity to protect parts.
3) Just because it can run on 87 octane, doesn't mean it'll run it's best.
4) Running big boost with lousy gas requires compromises, and those compromises will affect things, such as running incredibly rich, which is why you get fuel dilution issues.
5) Low viscosity oil, and big boost don't get along.

I consider big boost to be more than 7psi with a base engine CR of 9:1.

It's wanted to see if 87 octane would make a measurable difference at highway speeds and I thought watching timing advance on a engine at a fixed speed/load would be telling.

So recently I decided to test just a boring 2L with 9.5:1 CR, just watching the timing advance on cruise bumping down the highway, with a fully warmed engine and as similar a situation I can manage. 115Kph, manual trans in 5th, 3200rpm(iirc) and tires at 35psi.

Timing advance results via OBD2 and Torque Pro with an OBD MX BT adapter:

87 Octane: 28 - 32 degrees, bouncing around a lot
91 Octane: 39 - 40 degrees, rarely moved

The OM of this 16V DOHC VVT engine, says to run it on 87 octane.

Edit: Yes, I realize that my post will likely garner a lot of hate, but eh, it was mine and their experience

 

[LeakySeals]

Originally Posted by kschachn

Also, a thicker oil gets hotter than a thinner one. There are more shear forces in the bearings and this warms a thicker oil up more than one than one which is thinner. It also takes more energy to move a thicker oil, that energy has to go somewhere and it is into the oil.

I have noticed the thinner oils don't create as much varnish. Maybe this is one of the reasons.