Less oil loss with T6 vs M1 European in the VW?

[Johnny248]

Quick background. '08 VW Beetle 2.5l , ~160k

Factory interval is 10k, however I shoot for no more than about 7500k due to age of engine, possible consumption in the past, and personal preference.

The last time I changed the oil I used M1 0w40 Euro on the recommendaion of several members here. This oil had 7785 miles (couple hundered more than I normal aim for). Before draining it, I checked the level and it was at least 1.5 QTS low. I topped it off to see exactly how low it was, even though I was about to drain it.

Now, the previous two changes before the M1 were using Demo 400LE Syn 5w40, followed by Rotella T6.

Each of those ran for ~7500 miles without any noticiable loss of oil on the dip stick.

So, needless to say I went back to the T6 this time.

Anyway, I am not here to say anything negative about the apparent loss/consumption/evaporation of 1.5 QTS of oil while using the M1 (we all know that many OEMS would have no real problem with 1.5qts of use over 7500miles), but I am more interested in learning why there is such a difference between the M1 and the two diesel oils I used.

Would this be something related to NOACK numbers? I wasn't able to find any offical specs on any of the three oils, but I saw someone posted the M1 is 8.7

If it isn't NOACK, what other properties of the oil, or what about it would end up making one use 1.5 QTS, while the other two immeasurable?

Is this the difference between diesel oils and gasoline oils?

 

[147_Grain]

Mobil 1 0W-40 will likely perform very similar to T-6 in your application after a couple OCI's.

Sometimes an engine will use a little oil when changing brands and 1 1/2 quarts in almost 8,000 miles on an engine with 160K isn't bad at all.

 

[Revving2Redline]

Run T6 and if you are worried on wear numbers then uoa it.

 

[Johnny248]

I am not too concerned about wear numbers. VW says run these for 10k. A little longer than I like. I figured that the engine has made it this far, and it gas a good chunk of unknown history as far as what kind, and how often the oil was replaced. I feel comfortable running pretty much any syn 5w40 in it regardless of whether or not it has a 502 rating.

I was just wondering what about these oils makes one stick around longer in the engine.

I hear what you are saying about some oils being consumed a little more when switching oils. But why does this happen?

 

[OVERKILL]

The HDEO's are a fair bit heavier. I know they are all 40 weights, but M1 0w-40 is on the low side whilst the others are in the middle or near the top.

Also, you may get some consumption on the first OCI or two with a different lubricant. Doesn't always happen, but is sometimes the case.

And definitely not a NOACK issue.

 

[CT8]

T6 is a higher viscosity.

 

[sicko]

It's also happened before where switching to M1 caused consumption for the first one or two OCIs, but then it went away on its own.

No clue what caused it, or why it happens, but it's been reported on here quite a bit.

I suspect the consumption would've gone away if you had used M1 again.

 

[Delta]

2.5's have a tendency to burn oil later on in life. T6 is a little on the thick side so it seems like it's helping your consumption issue. I ran T6 when I was in a hotter climate (also used it to clean the previous owners 10K oci crud) but switched to Edge 0w40 now that it will see PA and NY winters. No noticeable consumption in the past couple k's. My engine does have 100K less than yours though...

 

[edyvw]

T6 is heavier oil. I used it in my friends Passat. I put Castrol 0W30 (GC at that time) and it was using oil maybe 1qt in 1500-2000 miles. T 6 would be around 0.5-1qt short after 5K. It is just heavier grade once it reaches optimal temperature (14.2 compare to 13.5 in M1 0W40).
For gas engines M1 is better in every aspect, BUT your engine probably shows some wear inside after 160K, and using little bit heavier grade is nothing uncommon at that mileage.

 

[Bluestream]

Originally Posted By: Johnny248
I topped it off to see exactly how low it was, even though I was about to drain it.


Why didn't you drain it then pour it in a jug to see how much you had? Topped it up before draining?