20w-50 in 2010 Outback 2.5

[wyo_00_]

I took my 2010 2.5 Outback with 190k miles on it to the local guy who works on Subarus for an oil change, and when I picked the car up the sticker in the window said 20w-50.

I asked if this was correct because for the last 12 years of owning my car I have only ever had 5w-30 put in. The mechanic told me that at my high mileage and the elevation we live at (~7500ft) that the 20w-50 is what my car needs.

I have since talked with multiple other mechanics about it and received different opinions and answers. Mostly saying that the 20w-50 is okay to use now during the summer but will need to go back to a thinner oil in the winter, and others say that the 20w-50 is for tractors and if I keep it in my car any longer the engine will explode.

My Outback doesn't have any leaks or any other major oil-related issues, except that it burns a little oil in between oil changes (most do at this age). The manual also says that 20w-50 is okay for severe driving conditions, however, I wouldn't necessarily consider my daily driving to the golf course severe.

So BITOG....will my engine explode if I keep the 20w-50 in it or am I overreacting? Would you find a new mechanic?

 

[kschachn]

What do you think will happen?

 

[BMW Dom]

What do you think will happen?

Obviously, it's gonna explode. If not, CAFE will team up with the SWAT and federal agents, and their house will be surrounded in a matter of a few hours. Very scary

 

[SubLGT]

Leave it in for the summer, go back to 5w30 in the winter.

 

[cvlw]

Is this a trustworthy local guy? If so, it might be worth accepting what he says.
Is 20w50 "allowed" in the manual?
Feel very free to ask him questions. The jump from 5w30 to 20w50 is a bit wide with a lot of common grades in between..

 

[ARCOgraphite]

Too heavy for a low stress wasserboxer or ウォーターボクサー
Can you feel any windage loss with this heavier oil on the way to the golf course?
Engine will be fine through mid Fall but go back to a 10W30 for Winter.
Actually I am surprised that car moves at all at 7500 ft

Colorado?

 

[wpod]

What do you think will happen?

The 20w-50 will not fit into the nooks and crannies in the Subaru engines?

 

[Jmlo96]

My guess is you will be getting a check engine light with variable valve timing codes very soon.

 

[kschachn]

My guess is you will be getting a check engine light with variable valve timing codes very soon.

Really. That’s quite a guess.

 

[PimTac]

So this Subaru has given you 190,000 miles on 5W-30 but suddenly you should be using 20W-50?

Winter is just around the corner for you at 7500 feet. I would change it before it gets too cold.

 

[kschachn]

The 20w-50 will not fit into the nooks and crannies in the Subaru engines?

I wonder that the nook and cranny tolerances are in that engine?

 

[BMW Dom]

The 20w-50 will not fit into the nooks and crannies in the Subaru engines?

 

[ARCOgraphite]

My guess is you will be getting a check engine light with variable valve timing codes very soon.

No VVT on that engine. I already just posted its easy on oil

It employs i-AVLS; the Subaru version of VTEC

 

[atikovi]

What do you think will happen?

So BITOG....will my engine explode if I keep the 20w-50 in it or am I overreacting?

He thinks it will explode.

 

[atikovi]

If it seems slow crank as the weather gets colder, change it to 5W50.

 

[ARCOgraphite]

You don't want slow drainback from the head(s) on a horizontally opposed engine that is known for flooding its spark plug tubes.

Plus - less oil cooling as another deficit to a 20w50.

OP will be OK till late Fall. It's right around the corner.

 

[ripcord]

I think it will be fine during the summer months.

 

[Rhymingmechanic]

By your username, I'm guessing you are in Wyoming. The 20W-50 would be fine if you're climbing mountain passes all summer or blasting around the Bighorn Basin in 100-degree heat, but it's overkill for driving back and forth to the golf course. And it will not be ideal when nights start getting cold in what, another month?

The manual says 20-50 is ok, but does it have a chart showing the temperature ranges for the different viscosities? Your winter temps will probably be lower than the recommended minimum for that oil, so definitely change to a lower viscosity for the winter. If you think a thicker oil is needed, there are less extreme options like high mileage 5W-30 and 0W-40. I personally would try to find an oil that works year-round, so there's no need to change based on the season vs. miles on the oil.

The mechanic is another issue. If you are in Wyoming, and depending on where, he might be the only Subaru guy in the county. If he does good work otherwise, maybe you can start a conversation with him as CVLW suggested, assuming he's not the type to get all bowed up because you're questioning him. If you're in one of the bigger towns/cities, there should be other Subaru specialists around.

 

[kschachn]

Anything above freezing is fine for a 20W winter rating.

 

[wyo_00_]

By your username, I'm guessing you are in Wyoming. The 20W-50 would be fine if you're climbing mountain passes all summer or blasting around the Bighorn Basin in 100-degree heat, but it's overkill for driving back and forth to the golf course. And it will not be ideal when nights start getting cold in what, another month?

The manual says 20-50 is ok, but does it have a chart showing the temperature ranges for the different viscosities? Your winter temps will probably be lower than the recommended minimum for that oil, so definitely change to a lower viscosity for the winter. If you think a thicker oil is needed, there are less extreme options like high mileage 5W-30 and 0W-40. I personally would try to find an oil that works year-round, so there's no need to change based on the season vs. miles on the oil.

The mechanic is another issue. If you are in Wyoming, and depending on where, he might be the only Subaru guy in the county. If he does good work otherwise, maybe you can start a conversation with him as CVLW suggested, assuming he's not the type to get all bowed up because you're questioning him. If you're in one of the bigger towns/cities, there should be other Subaru specialists around.

Yes, I'm in Wyoming. I really do not drive very far at all, maybe 50 miles a week with the occasional trip to Colorado on the weekends.

I honestly do not know if a thicker oil is needed. I have used synthetic 5w-30 forever and just now started to notice that the oil was burning a bit.

The 20w-50 seemed like overkill to me.