Mobil1 10w40 HM burns like water.

[Graham Piccinini]

In my Lexus IS300 I have been using bunch of oils and so far had great luck with 0w40 oils, all except for Castrol 0w40. But that's not the point. So summer came to North Carolina and temperatures of 65-85 started appearing. So I figured that I could go ahead and use up some Mobil1 10w40 High Mileage from my stash for the summer months. And guess what? Mobil 1 High Mileage 10w40 dissapeared on the dipstick faster than SRT 0w40, or Mobil1 0w40, or Castrol 0w40, or Redline 0w40, or even Pennzoil Euro 5w40. How is that possible?
I was always under the impression from this forum that the M1 HM 10w40 is the GO-TO oil if your engine has oil consumption issues. So how the heck did my engine consume it so freaking quick compared to much less viscous oils? I topped it off with some SRT 0w40. My usual consumption is 1qt per 3500-5000 miles. When I just started using SRT 0w40 - I had initial consumption of 1.5qt in 700 miles, but absolutely no consumption until the end of that 5k oci. And Now M1 HM 10w40 dropped level by a quart in just under a 1000 miles. Isn't it supposed to be one of the most consumption stopping oils ever made? Just wondering, thanks for replies, facts, and opinions. Love this community

 

[Leo99]

According to the cognoscenti on here, Valvoline MaxLife HM is the go-to HM oil.

 

[Pontual]

3 causes. Most 10w40 are of lesser base quality and even semi syn oils when compared with those 0w40. 0w40 are mostly fully syn oils. That way on 10w40 it is needed more VII to get the 40 at op temp. Depending on the quality of those VI improvers, they shear way more than a 0w40 (fully syn with better vii quality). The excess shearing make the oil thinner. Going thinner it get more flow over to the pistons, from the pushrod canal and more splash to the cylinder walls and is burnt on cc by the volume wedge phenomena when the scrapper can't handle the excess. So you burn more, from shear. Now that it is thinner it gets more splashed form of oil cloud, pulverized and spraying inside the cranckcase and that get sucked up as mist by the pcv system. So a more stable oil (fully 0w40), won't get burnt as much, since they have more vi but less vii. Better oil base make lower volatization with better noack numbers from 0w40.

So, the 3 causes in this case are: 1) thinning from shearing causing wedge of oil past ring to cc; 2) sucking out from pcv and also burnt at cc; 3) volatization from higher noack values (evaporation).

 

[DuckRyder]

Water burns?

 

[Pontual]

Hot water burns. I found that making coffee.

 

[Gasbuggy]

Seems like your engine has a high initial burn rate when switching oil?

 

[deven]

Pontual hit it on the head in my opinion. 0w40 are usually long drain oils so they usually contain more PAO oil in it which is more shear stable. I'm willing to bet that the 10w40 has little to no PAO but is mainly a group III hydrocracked product.

 

[901Memphis]

I would continue with the course and see if consumption changes. You need more than a few thousand miles with a different oil before you can see normal consumption.


It's been discussed here before and I've personally noted it myself that switching brands can cause temporary consumption in vehicles that normally have little or none.

If it stays that way I would switch to Maxlife syn blend 10w40

 

[Graham Piccinini]

Originally Posted By: Pontual
3 causes. Most 10w40 are of lesser base quality and even semi syn oils when compared with those 0w40. 0w40 are mostly fully syn oils. That way on 10w40 it is needed more VII to get the 40 at op temp. Depending on the quality of those VI improvers, they shear way more than a 0w40 (fully syn with better vii quality). The excess shearing make the oil thinner. Going thinner it get more flow over to the pistons, from the pushrod canal and more splash to the cylinder walls and is burnt on cc by the volume wedge phenomena when the scrapper can't handle the excess. So you burn more, from shear. Now that it is thinner it gets more splashed form of oil cloud, pulverized and spraying inside the cranckcase and that get sucked up as mist by the pcv system. So a more stable oil (fully 0w40), won't get burnt as much, since they have more vi but less vii. Better oil base make lower volatization with better noack numbers from 0w40.

So, the 3 causes in this case are: 1) thinning from shearing causing wedge of oil past ring to cc; 2) sucking out from pcv and also burnt at cc; 3) volatization from higher noack values (evaporation).


That makes perfect sense now. Thank you very much! I'm surprised that thought haven't even crossed my mind until you brought it up.

 

[Graham Piccinini]

Originally Posted By: 901Memphis
I would continue with the course and see if consumption changes. You need more than a few thousand miles with a different oil before you can see normal consumption.


It's been discussed here before and I've personally noted it myself that switching brands can cause temporary consumption in vehicles that normally have little or none.

If it stays that way I would switch to Maxlife syn blend 10w40


I'll run it as is, top off as needed, but will switch back to SRT 0w40, since I got a lot of it on Chistmas sale at AZ.

 

[Graham Piccinini]

Originally Posted By: Gasbuggy
Seems like your engine has a high initial burn rate when switching oil?


Seems like it, but I still don't know why. None of my other engines have ever done this.

 

[Graham Piccinini]

Originally Posted By: DuckRyder
Water burns?


Yea, didn't think this one through... But water does make fire more flammable and explosive when you try to use water to put out a fire on magnesium wheels or something.

 

[Chewie]

Notice any smoke?

 

[BrocLuno]

M1 HM 10W-40 was never my go-to for anything ...

Maxlife

 

[Graham Piccinini]

Originally Posted By: Chewie
Notice any smoke?

No smoke, neither at start ups or after normal driving or after hard runs.

 

[dlundblad]

I have had great luck with M1 10w30 HM. It is a very over-looked oil here IMO and blows all other HM synthetics out of the water. I agree on giving the 10w40 HM more time.

If something burns this bad, I would simply use cheap conventional. You're in the NC. Why not Supertech 15w40?

If you want more experimentation, Walmart now carries Valvoline 15w40 High Mileage. I'd almost entertain running that in the Volvo in the summer.

 

[tig1]

Originally Posted By: RusskiBoSS
Originally Posted By: Pontual
3 causes. Most 10w40 are of lesser base quality and even semi syn oils when compared with those 0w40. 0w40 are mostly fully syn oils. That way on 10w40 it is needed more VII to get the 40 at op temp. Depending on the quality of those VI improvers, they shear way more than a 0w40 (fully syn with better vii quality). The excess shearing make the oil thinner. Going thinner it get more flow over to the pistons, from the pushrod canal and more splash to the cylinder walls and is burnt on cc by the volume wedge phenomena when the scrapper can't handle the excess. So you burn more, from shear. Now that it is thinner it gets more splashed form of oil cloud, pulverized and spraying inside the cranckcase and that get sucked up as mist by the pcv system. So a more stable oil (fully 0w40), won't get burnt as much, since they have more vi but less vii. Better oil base make lower volatization with better noack numbers from 0w40.

So, the 3 causes in this case are: 1) thinning from shearing causing wedge of oil past ring to cc; 2) sucking out from pcv and also burnt at cc; 3) volatization from higher noack values (evaporation).


That makes perfect sense now. Thank you very much! I'm surprised that thought haven't even crossed my mind until you brought it up.


Actually he's most likely wrong as to why your engine has high oil consumption except with the possibility of the PCV problem.

 

[Graham Piccinini]

Originally Posted By: dlundblad
I have had great luck with M1 10w30 HM. It is a very over-looked oil here IMO and blows all other HM synthetics out of the water. I agree on giving the 10w40 HM more time.

If something burns this bad, I would simply use cheap conventional. You're in the NC. Why not Supertech 15w40?

If you want more experimentation, Walmart now carries Valvoline 15w40 High Mileage. I'd almost entertain running that in the Volvo in the summer.


Because 0w40 works great at burns at a pretty slow rate. And I got a huge stash of it. Now if I start driving like a normal person - it will probably stop burning oil all together. I think the reson why it burns oil is because it barely leaves the 4000-6000 rpm zone. Too much fun with that thing, impossible to drive slow on it. Not the most powerful, or best handling, or most fuel efficient, but the smiles-per-gallon factor definitely fixes all that for me

 

[Pontual]

Originally Posted By: tig1
Originally Posted By: RusskiBoSS
Originally Posted By: Pontual
3 causes. Most 10w40 are of lesser base quality and even semi syn oils when compared with those 0w40. 0w40 are mostly fully syn oils. That way on 10w40 it is needed more VII to get the 40 at op temp. Depending on the quality of those VI improvers, they shear way more than a 0w40 (fully syn with better vii quality). The excess shearing make the oil thinner. Going thinner it get more flow over to the pistons, from the pushrod canal and more splash to the cylinder walls and is burnt on cc by the volume wedge phenomena when the scrapper can't handle the excess. So you burn more, from shear. Now that it is thinner it gets more splashed form of oil cloud, pulverized and spraying inside the cranckcase and that get sucked up as mist by the pcv system. So a more stable oil (fully 0w40), won't get burnt as much, since they have more vi but less vii. Better oil base make lower volatization with better noack numbers from 0w40.

So, the 3 causes in this case are: 1) thinning from shearing causing wedge of oil past ring to cc; 2) sucking out from pcv and also burnt at cc; 3) volatization from higher noack values (evaporation).


That makes perfect sense now. Thank you very much! I'm surprised that thought haven't even crossed my mind until you brought it up.


Actually he's most likely wrong as to why your engine has high oil consumption except with the possibility of the PCV problem.


Ow really. Now why? Kk

 

[Graham Piccinini]

Originally Posted By: tig1

Actually he's most likely wrong as to why your engine has high oil consumption except with the possibility of the PCV problem.


Consumption is pretty stable on 0w40s. Hopefully it straightens out. Could PCV system cause sudden intermediate oil consumptions like that? Or did switching brands cause the consumption? I'm leaning towards switching brands... Don't think that the PCV could cause intermediate consumptions like that in exactly the same time I switched brands and then just go back to little to no consumption. Maybe a coincedence and it is the PCV fault? Or maybe just initial consumption from switching brands? Idk...