Massive difference in oil consumption between 5W30 and 5W40

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Well, i tried Shell Helix Ultra 5w30 for my last oil change instead of the usual cheap Tech9 (i guess it's our equivalent of SuperTech) or Total Quartz 5w40. Usually at the end of a 8/10k kms oil change interval the level is below the middle on the dipstick. This time it is right on the middle after only 3000 kms. Is it normal to burn that much more oil with not that big of a difference in viscosity ? I always fill the engine close to the max level which is exactly 5.5 liters. In my experience so far, synthetic 5w40 seems to be the best to avoid consumption. The M111 engines i had all seem to consume more oil with 10w40 and 15w40 but i didn't think synthetic 5w30 would burn off that fast. 70% of my driving is highway between 2900 and 3300 rpm. Should i try 5w50 to decrease oil consumption even more ?
 
No, 10w30 isn't even available at all in PCMO, only some rare HDEOs or for garden equipment and boats.
 
Problem is that a 5w30 can be energy conserving and almost on the edge of being a 20 grade. Then a 40 grade can be close to a 50 grade or somewhere in the middle etc. So you can get 30 and 40 grade either very close together in viscosity or very far apart depending on their specs.

Generally SHU should be a thicker 30 grade though, if it's the A3/B4 version.

The other variable is that it's too soon to tell. Wait until the oil level drops to the lower mark and document how many kms were travelled and how many mL/L/quarts etc it takes to fill.
 
The oil i use isn't energy conserving, MB 229.5, 3.5 HTHS, 11.8 cSt. I think it drank half a liter in 3000 kms. SHU can be on the thin side indeed. Their 5w40 has a 100°c cSt of 12.8 while Total Quartz 5w40 is at 14.7.
 
You may know my tendency to use the Total 5W40 Energy in every 10+ car :D (tne Energy variand, with MB 229.5 approval, not the "regular" with "only 229.3")?

Maybe it's because it's slightly on the thick side, but I found it to work well in "oldish" engines (ie: with no DPF). Noise wise, and oil consumption wise. I don't know it's HTHS, but maybe it's more than 3,5, and that makes a difference?

I'm not sure why SHU 5W30 would create moi oil consumption. Sometimes engines need to "adapt" after a change of oil brand/type.
 
+1 on the Rimula R6M. BUT, it's a high SAPS (1,9 ?) I think. Maybe R6LM would fit too?

Oh, and you can usually find it in any truck store, the groupeauto chain for ex. Pretty cheap too.
 
I think that 1992-2003 era engine doesnt care about saps levels.... :) EURO what...2.....3 maybe?
 
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Well, i tried Shell Helix Ultra 5w30 for my last oil change instead of the usual cheap Tech9 (i guess it's our equivalent of SuperTech) or Total Quartz 5w40. Usually at the end of a 8/10k kms oil change interval the level is below the middle on the dipstick. This time it is right on the middle after only 3000 kms. Is it normal to burn that much more oil with not that big of a difference in viscosity ? I always fill the engine close to the max level which is exactly 5.5 liters. In my experience so far, synthetic 5w40 seems to be the best to avoid consumption. The M111 engines i had all seem to consume more oil with 10w40 and 15w40 but i didn't think synthetic 5w30 would burn off that fast. 70% of my driving is highway between 2900 and 3300 rpm. Should i try 5w50 to decrease oil consumption even more ?

When changing oil brands some consumption is normal. Keep an eye on it, if it persists, change brands again. I had this problem on our Expedition, it drank 3L of Amsoil SS 0w-30 over an OCI but wouldn't require anything on 10-12,000km intervals using M1 AFE 0w-30, 0w-40 or Motul 0w-30.
 
I'm not sure if anyone is interested but my brother has been using the straight Valvoline VR1 straight 50W racing oil. He has a Tracker with a Suzuki engine that makes a lot of timing chain noise and was burning a lot of oil between changes.

Since switching no more noise and it uses hardly any oil at all. We live in Southern CA so it never gets cold enough to give starting issues. I will say that the with the Fumoto valve that the motor has to be fully warmed up so it will drain out of the small hole.
 
You may know my tendency to use the Total 5W40 Energy in every 10+ car :D (tne Energy variand, with MB 229.5 approval, not the "regular" with "only 229.3")?

Maybe it's because it's slightly on the thick side, but I found it to work well in "oldish" engines (ie: with no DPF). Noise wise, and oil consumption wise. I don't know it's HTHS, but maybe it's more than 3,5, and that makes a difference?

I'm not sure why SHU 5W30 would create moi oil consumption. Sometimes engines need to "adapt" after a change of oil brand/type.
Yes i've read a lot of posts where you mention that oil and i also think it is very good. I buy it on sale at Leclerc and it's always the non Energy version, it carries the 229.5 approval.
Try Shell Rimula R6M 10W-40....

LC has 400.000kms....and is not burning that oil....
I've been interested by this oil but i don't think it would do great with my gasser and the fact it burns E85 since it doesn't have the API SN rating.
When changing oil brands some consumption is normal. Keep an eye on it, if it persists, change brands again. I had this problem on our Expedition, it drank 3L of Amsoil SS 0w-30 over an OCI but wouldn't require anything on 10-12,000km intervals using M1 AFE 0w-30, 0w-40 or Motul 0w-30.
What would explain that ? Even with the same brand, formulations are evolving. Maybe the engine was unhappy to see a Shell jug. :LOL:
 
What would explain that ? Even with the same brand, formulations are evolving. Maybe the engine was unhappy to see a Shell jug. :LOL:

Change in chemistry usually; oils having vastly different additive packs and base oil blends. It's interesting to see how some respond with a very rapid taper off of consumption, whereas in other cases, like with my Expedition, it never settles down (I gave it a couple of OCI's to do so) and one is forced to go with a different lubricant.

While it's true that formulations are constantly evolving, you don't typically see significant changes in formulation for a given brand and product. You might see the base oil blend change, or some additives levels change, but it's typically not dramatic. On the other hand, something like the Ravenol I'm running in my SRT has completely different additive levels and types as well as base oils from the SRT 0w-40.
 
What would cause the consumption to slow down after a while ? Do you think the different formulation/chemistry has more to do with the burning than the grade itself ?
 
What would cause the consumption to slow down after a while ? Do you think the different formulation/chemistry has more to do with the burning than the grade itself ?
Different additives compete for surface space so as the old additives are removed and the new additives lay down I expect that process creates some consumption. Once the process begins to slow down and the additives from the new lube are laid down you see the consumption taper off is my theory.
 
I will see how it evolves but it makes sense. When i had the car i didn't know what brand was used before but i started using Total and it burned a bit more oil during the first months and then it stopped. I had this experience with other cars as well. Before trying the 5w30 i used some 10w40 and similarly the engines consumed more of it (but clearly not as much as 5w30). I also think that the fact my driving is mostly high rpm/high vacuum exacerbates the tendency of lighter oils to disapear quicker.
 
Well, i tried Shell Helix Ultra 5w30 for my last oil change instead of the usual cheap Tech9 (i guess it's our equivalent of SuperTech) or Total Quartz 5w40. Usually at the end of a 8/10k kms oil change interval the level is below the middle on the dipstick. This time it is right on the middle after only 3000 kms. Is it normal to burn that much more oil with not that big of a difference in viscosity ? I always fill the engine close to the max level which is exactly 5.5 liters. In my experience so far, synthetic 5w40 seems to be the best to avoid consumption. The M111 engines i had all seem to consume more oil with 10w40 and 15w40 but i didn't think synthetic 5w30 would burn off that fast. 70% of my driving is highway between 2900 and 3300 rpm. Should i try 5w50 to decrease oil consumption even more ?
I would suggest filling the oil only to the midpoint on the stick. More than that just goes up in the PCV valve and into your intake. That's what I do on my MB's and even my Harley. The oil level never fluctuates. In the case of the Harley, there's no oil in the intake under the air cleaner. Give it a try.
 
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