2019 Ascent towing pop-up with 5w20

[TacoFergie]

The CVT was an issue on the 19's from what I've seen. There are quite a few people on Ascent pages towing larger campers that have 50k miles with no issues.

As far as oil weight....I've never been a fan of altering from whats recommended by the manufacture on a stock engine. Now if it was an older worn out engine or you were racing, thats whole different topic. If anything I would just use 0w-20 and shorten the oil change interval during the times that you are towing to 3k. I doubt anything bad will happen if you use a heavier weight oil, but is it really benefiting anything?

I'm going to have to check out the Outback forums and see what those guys are saying about their oil choices and analysis. Seems they are more into it than the Ascent crowd. We have a 21 Ascent and I asked a similar question about oil recommendations a few days ago. Basically what came out of it was just keep up with OCI's and use a decent quality 0w-20 oil.

 

[CheezWhiz]

You need a Peterbilt with straight 90w in the crankcase, or you are gonna blow something up.

 

[Ignatius]

The CVT was an issue on the 19's from what I've seen. There are quite a few people on Ascent pages towing larger campers that have 50k miles with no issues.

As far as oil weight....I've never been a fan of altering from whats recommended by the manufacture on a stock engine. Now if it was an older worn out engine or you were racing, thats whole different topic. If anything I would just use 0w-20 and shorten the oil change interval during the times that you are towing to 3k. I doubt anything bad will happen if you use a heavier weight oil, but is it really benefiting anything?

I'm going to have to check out the Outback forums and see what those guys are saying about their oil choices and analysis. Seems they are more into it than the Ascent crowd. We have a 21 Ascent and I asked a similar question about oil recommendations a few days ago. Basically what came out of it was just keep up with OCI's and use a decent quality 0w-20 oil.

Based on the Subaru FA24F engine UOA data that I have seen to date, these are the conclusions I have come to:

1. The 3000 mile severe service interval should be the standard that everyone should follow.
2. This engine has issues with fuel dilution and oil shearing.
3. Resource conserving Xw-30 oils tend to shear down twice as quickly as 0w20 oils in this engine making the end result not much different between the two different grades over similar time and mileage durations.

 

[TacoFergie]

Based on the Subaru FA24F engine UOA data that I have seen to date, these are the conclusions I have come to:

1. The 3000 mile severe service interval should be the standard that everyone should follow.
2. This engine has issues with fuel dilution and oil shearing.
3. Resource conserving Xw-30 oils tend to shear down twice as quickly as 0w20 oils in this engine making the end result not much different between the two different grades over similar time and mileage durations.

Those are good points.

1. The 3000 mile severe service interval should be the standard that everyone should follow.
- I'll have to look into this, is that even on "regular driving habits" or is this for people that tend to drive harder?

2. This engine has issues with fuel dilution and oil shearing.
- I wonder why this happens more so than other engines? I'm a nerd and like to know why certain things happen in one engine and not as much as others. Just like why Porsche isn't known for piston slap like Subarus are. I believe that it's probably due to lower mileage, shorter OCI and possibly longer piston skirts are part of it.

3. Resource conserving Xw-30 oils tend to shear down twice as quickly as 0w20 oils in this engine making the end result not much different between the two different grades over similar time and mileage durations.
- I'm going to have educate myself more on 5w-30 oils, 0w-30 oil is not locally available. My theory why a Xw-30 oil shears twice as fast as a Xw-20 is that they generally tend to shear at a faster rate due to being a wider viscosity range (which tend to shear sooner than narrower viscosity ranges), oil pump gear tolerances (among other close tolerance and high pressure/heat areas) being designed around a 0w-20 that would likely cause an Xw-30 oil to be pressurized (which also causes fluid temp increase) higher than it's designed to thus permanently shearing to a lower viscosity and because there is more resistance to flow through oil passages/pump will causes more pressure...then causing oil temperatures to increase which also increase oil shearing. I'm no scientist but these are observations I've noted while researching oil shearing. I'm not saying these are solid facts, but just my thoughts and I welcome criticism as I'm always learning.

Again, I don't think running an Xw-30 is going to hurt anything, nor am I saying anyone is right or wrong on the subject. But I'm not seeing the benefit.

 

[The Critic]

5,000 pounds is way too much to tow behind an Ascent. That amount of weight is the "sweet spot" for many half-ton trucks-regardless of what the specs are. So towing 5,000 pounds with an Ascent.....well.

Agreed. I am somewhat suspicious of towing anything of that size with car-based crossovers. The towing capabilities of these vehicles appear to be an afterthought at best.

If one participates on any of the pick-up truck boards you will quickly read how much trouble folks have with towing "light loads" on their 1/2 ton trucks. Can't imagine how ugly it'd get for a crossover when towing a similar sized load.

 

[Ignatius]

Those are good points.

1. The 3000 mile severe service interval should be the standard that everyone should follow.
- I'll have to look into this, is that even on "regular driving habits" or is this for people that tend to drive harder?

2. This engine has issues with fuel dilution and oil shearing.
- I wonder why this happens more so than other engines? I'm a nerd and like to know why certain things happen in one engine and not as much as others. Just like why Porsche isn't known for piston slap like Subarus are. I believe that it's probably due to lower mileage, shorter OCI and possibly longer piston skirts are part of it.

3. Resource conserving Xw-30 oils tend to shear down twice as quickly as 0w20 oils in this engine making the end result not much different between the two different grades over similar time and mileage durations.
- I'm going to have educate myself more on 5w-30 oils, 0w-30 oil is not locally available. My theory why a Xw-30 oil shears twice as fast as a Xw-20 is that they generally tend to shear at a faster rate due to being a wider viscosity range (which tend to shear sooner than narrower viscosity ranges), oil pump gear tolerances (among other close tolerance and high pressure/heat areas) being designed around a 0w-20 that would likely cause an Xw-30 oil to be pressurized (which also causes fluid temp increase) higher than it's designed to thus permanently shearing to a lower viscosity and because there is more resistance to flow through oil passages/pump will causes more pressure...then causing oil temperatures to increase which also increase oil shearing. I'm no scientist but these are observations I've noted while researching oil shearing. I'm not saying these are solid facts, but just my thoughts and I welcome criticism as I'm always learning.

Again, I don't think running an Xw-30 is going to hurt anything, nor am I saying anyone is right or wrong on the subject. But I'm not seeing the benefit.

1. The 3000 mile severe service interval is recommended for those who tow, drive hard, often short trip the vehicle, etc. My contention is that this engine is hard enough on oil that even under the best conditions the 3000 mile interval is merited.

2. I have commented elsewhere that I personally believe it has much to do with emissions "savings." The strategy that the automotive industry seems to have adopted with direct injection engines is to allow more blowby in the combustion process so that fewer carbon emissions go out the tailpipe and instead end up in the crankcase.

3. I consider resource conserving oils to be weaker than those that are not insofar as their composition and ability to perform. The industry has shifted it priorities to what saves on emissions and fuel arguably above all else.

I still think that using a dual rated HDEO like Rotella T6 Multi Vehicle 5w30 is the way to go.