Finding an oil that doesnt burn off as fast

If you read my post attentively, you'll notice I said: "I just looked at Castrol's website". If, when you get a chance, you'll go over there to take a look yourself, you will definitely find only one product data sheet for 5w40 and one for 0w40. There are no old and new data sheets in there - you seem to be confused. Those respective data sheets show that 5w40 is definitely a smidge thicker with a definitive extra manufacturer certification vs 0W40
Ok, my apologies. Castrol changed 0W40 pds on 04/25/2022. I didn’t see new pds on the last month.
Regardless of approvals, 0W40 is still PAO based oil. But I don’t that the pour point jumped to -45.
 
After having tried Mobil 1 0W-40 FS, Liqui Moly Leichtlauf 5W-40 and Castrol 0W-40 in my M272 engined Mercedes, driving the same route, same filter, same OCI (6500 miles) I have the following conclusions: Oil consumption was the greatest with the Mobil 1. Also, fingers and nose (not a scientific test, just sharing observations) say that it feels most watery and smells the worst. Consumption was about 1qt every 3500 miles. Liqui Moly was next, a bit better when it came to consumption 1qt every 4200 or so miles. Felt and smelt better when taking it out. The Castrol is currently in and the oil level according to the dipstick has not moved and I've done 4800 miles with it. In 1200 miles I will take it out and see how it is. The next oil will be PUP 0W-40 due to the $25 rebate. :) The lack of availability of Castrol 0W-40 at a good price and the want to try all easily available 229.5 oils is what lead me to the PUP.
 
After having tried Mobil 1 0W-40 FS, Liqui Moly Leichtlauf 5W-40 and Castrol 0W-40 in my M272 engined Mercedes, driving the same route, same filter, same OCI (6500 miles) I have the following conclusions: Oil consumption was the greatest with the Mobil 1. Also, fingers and nose (not a scientific test, just sharing observations) say that it feels most watery and smells the worst. Consumption was about 1qt every 3500 miles. Liqui Moly was next, a bit better when it came to consumption 1qt every 4200 or so miles. Felt and smelt better when taking it out. The Castrol is currently in and the oil level according to the dipstick has not moved and I've done 4800 miles with it. In 1200 miles I will take it out and see how it is. The next oil will be PUP 0W-40 due to the $25 rebate. :) The lack of availability of Castrol 0W-40 at a good price and the want to try all easily available 229.5 oils is what lead me to the PUP.

I've tried all same oils in my M119 engined Merc and had zero oil consumption even through a 7,500 OCI
 
It could be that my car is problematic. I am at 196k at this point. Previous owner serviced it at a shop where they put Motul 300V 15W-40 for at least 3 OCI, no idea why...
 
Curious what is the Noack, KV100, vm and HTHS delta (% diff) between the oils that op was using.
I assume the % differences can't be that significant to cause or stop major oil consumption ... At least not based on these 3 or 4 (including vm) variables assuming they are close enough % wise.
Other forces maybe at work here.
 
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Hmmm, I understand the logic. But how do we judge that Castrol 0w40 is better than 5w40 then? I read that "pao" is better, but so is the smaller spread between cold and hot flow 🤔.
PAO is better how because ever base oil has its + and - That is why most oil are a blend.
 
PAO is better how because ever base oil has its + and - That is why most oil are a blend.
In this case, it's possible that they may be using a heavier PAO vs a lighter Group III, but we really don't know for sure if that's actually the case. Castrol won't use PAO unless they feel they absolutely have to, as we heard from a former employee on here.

If we look at Gokhan's BOV estimates:
Castrol Edge 0W-40 BO: 7.34cSt @ 100C
Castrol Edge 5W-40 BO: 7.03cSt @ 100C

This does appear to support the premise that the 5W-40 actually uses thinner bases (because of no PAO) than the 0W-40.

Historically, the 0W-40 also had more approvals than the 5W-40, but we are kind of splitting hairs there.
 
So we're calling Castrol Edge 0w40 as slightly superior to Mobil 1 0w40?

I might try it in the 2AZ oil burner in Project xB, see if it makes a difference

How much thicker at operating temp will the 0w40 be over your run of the mill (say Maxlife) 5w30?
 
So we're calling Castrol Edge 0w40 as slightly superior to Mobil 1 0w40?

I might try it in the 2AZ oil burner in Project xB, see if it makes a difference

How much thicker at operating temp will the 0w40 be over your run of the mill (say Maxlife) 5w30?
Well, just looking at the PDS of both, the 0W-40 will be "thicker" at temp with a KV100 of 12.7 and VI at 198. The Valvoline 5W-30 Maxlife is 11.0 with a VI of 161. Don't know if HTHS is a concern with a vehicle pushing 300K, but the Castrol is >3.5 while the Valvoline is 3.1. Also, don't know what you are trying to achieve, but if it's something to do with using a Euro type 40wt, why not go cheap and use the Quaker State Euro 5W-40? Especially if it's high consumption.
 
So we're calling Castrol Edge 0w40 as slightly superior to Mobil 1 0w40?

I might try it in the 2AZ oil burner in Project xB, see if it makes a difference

How much thicker at operating temp will the 0w40 be over your run of the mill (say Maxlife) 5w30?
I'm not, I am however suggesting that it (Castrol 0W-40) is better than Castrol's 5W-40.
 
So we're calling Castrol Edge 0w40 as slightly superior to Mobil 1 0w40?

I might try it in the 2AZ oil burner in Project xB, see if it makes a difference

How much thicker at operating temp will the 0w40 be over your run of the mill (say Maxlife) 5w30?
If I may offer advice; a oil burning 2AZ-FE will soon kill both cat converters. I’d do some piston soaks as member Elkins45 did and he had success. It’s doubtful a 0w40 will help much. Keep oil level topped off
 
If I may offer advice; a oil burning 2AZ-FE will soon kill both cat converters. I’d do some piston soaks as member Elkins45 did and he had success. It’s doubtful a 0w40 will help much. Keep oil level topped off
I'd suggest he use an HPL product at this juncture, as I think he has already done a piston soak (if this is the xB we are discussing). While M1 0W-40 has AN's and esters, it is not in the volume that @High Performance Lubricants uses.
 
If you're comfortable doing it, I'd slap in Delvac 5W-40 and see how the engine will go along. You can't go wrong with Castrol though.
 
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