Thin oil for better winter performance

Status
Not open for further replies.
Joined
Jul 1, 2014
Messages
2,078
Location
Canada
My car (2005 325i) takes a lot longer to heat up in the winter than some of my previous cars.

The car feels rather sluggish in the winter. In the summer the engine runs super smooth and is a lot more responsive.

Do you think switching from a 0W40 oil to a thinner one can improve my winter performance?

How thin do you think I could go on a M54 motor?

If you are thinking thermostat, mine is 2 years old. It seems to operate at 92 Celsius instead of 97 Celsius like it's supposed to. However, there are only two brands available, Behr and Wahler. One brand leaks from the temperature sensor and one brand runs a bit cool. So given the choice between the two I would rather run a few degrees cold than leak coolant.
 
Great oil, keep using it. Slow warm up could be a design feature or your thermostat needs replacement.
 
Originally Posted By: JohnnyJohnson
Originally Posted By: camrydriver111
How thin do you think I could go on a M54 motor?


What does your owners manual say?


I think it says 5W30 ACEA oil.

Originally Posted By: rfeir
Great oil, keep using it. Slow warm up could be a design feature or your thermostat needs replacement.


I think it's the design. Big engine, small displacement. The car also has a fan clutch.
 
Originally Posted By: camrydriver111


If you are thinking thermostat, mine is 2 years old. It seems to operate at 92 Celsius instead of 97 Celsius like it's supposed to.


I would still verify the thermostat is opening where it should and is fully closed when cold. The easiest way this can be done is with an IR thermometer if you or someone you know has one. A stuck-open thermometer will still cool the car obviously, but will cause it to warm more slowly. This has knock-on effects on performance just like you describe.

Run a 5w-30 or 0w-30 that meets the relevant BMW spec, but also check the thermostat. What you are describing is not caused by oil choice.
 
Originally Posted By: JC1
Where are you located in Canada? Can you use a block heater or that's not an option?
This ^^^^.
 
If it were me I would both block off the radiator and get a block heater installed. I do here in MN. Just running the block heater for an hour or so before launch helps a lot in getting the cabin warm way sooner and no need to have much air flow past the cooling system in winter. Helps mileage too.
 
Block heater is not an option.

My gut feeling is that if I replaced the thermostat it would be the same and I would be out $150.

That's why I am asking about the oil.
 
Originally Posted By: camrydriver111
Block heater is not an option.

My gut feeling is that if I replaced the thermostat it would be the same and I would be out $150.

That's why I am asking about the oil.


$150. Ouch. You can't purchase a genuine BMW thermostat which is absent the two issues you described earlier? (Not as the solution to your winter performance concern.)

You have not mentioned fuel as a means of improving winter performance.

Can you describe your fuel practice in both winter and summer?

EDIT:

Would an engine running at 92*C instead of the design 97*C not run slightly richer and therefore result in no change or possibly slightly improved acceleration rather than less?
 
Last edited:
Originally Posted By: ArcticDriver
Originally Posted By: camrydriver111
Block heater is not an option.

My gut feeling is that if I replaced the thermostat it would be the same and I would be out $150.

That's why I am asking about the oil.


$150. Ouch. You can't purchase a genuine BMW thermostat which is absent the two issues you described earlier? (Not as the solution to your winter performance concern.)

You have not mentioned fuel as a means of improving winter performance.

Can you describe your fuel practice in both winter and summer?


A genuine BMW thermostat is a re-branded Wahler which will leak from the temperature sensor. I actually replaced a Wahler after 5 months because it leaked and I can't tell a difference between my current thermostat other than the digital temperature readout.

I use the cheapest 91 octane fuel and I don't let the tank get too low in the winter. Fill up every other week.
 
Quote:
My gut feeling is that if I replaced the thermostat it would be the same and I would be out $150.

That's why I am asking about the oil.


Testing the thermostat is *free,* however. And what you should do before trying to force a diagnosis on an exceedingly unlikely cause. "Where you hear hoof beats, think horses...," etc. If the behavior is the same, that's a strong indicator it may NOT be the thermostat, but if you replaced one bad one with another, it wouldn't act differently. And that sometimes happens.

Another thing to investigate is the warming circuit for the throttle body. If the temp. sensor isn't working it could create this. I don't know if a code would be thrown on your car, presumably none are registering, correct? I would also verify the fan is not always on, providing extra cooling when it should not.

Arcticdriver also has a good point - if your area's winter fuel is particularly diluted, it will be the main cause if you are sensitive to it (I am; I feel it even in my granny-driven SUV). If you don't find a solution before winter, try buying real gas (there is an app for that which will show you who sells it - "Real Gas"). That could help neck down the problem.
 
Originally Posted By: camrydriver111
Originally Posted By: JohnnyJohnson
Originally Posted By: camrydriver111
How thin do you think I could go on a M54 motor?


What does your owners manual say?


I think it says 5W30 ACEA oil.

Originally Posted By: rfeir
Great oil, keep using it. Slow warm up could be a design feature or your thermostat needs replacement.


I think it's the design. Big engine, small displacement. The car also has a fan clutch.


ACEA doesn't rate oils by viscosity. Like the MINI I had, I bet the engine bay has a sticker that says Castrol/BMW oil is recommended. That marketing agreement has been dissolved. You can use any grade that meets BMW LL01.

If you run short trips of less than 20 miles I would say definitely run a thinner oil like M1 0w-30 or an A1/B1 oil that would be a 30 grade.

If your driving is more than 20 miles so you get some heat in the oil stick with the ACEA A3/B4 LL01 that BMW recommends.
 
You could also have drag from the (cold) differential. Change its oil to a good synthetic once and enjoy!

Also if you have an automatic its programming could be altered for better/ safer warmup at the expense of performance.
 
Originally Posted By: andyd
Do you know another Camry and could ask what normal is.


An M54 is an inline-6 BMW mill that was used in various displacements in a lot of cars 10 to 15 years ago. I don't think he's talking about a Camry.
wink.gif
These also had an electronically controlled thermostat instead of the normal strictly bi-metallic type. I wonder if that has anything to do with it, and I'd ask on a model-specific forum about other owners' experiences with winter performance and this issue. You are right, finding a consensus of what normal is could also help
 
How in the world did you manage to buy a car in Canada that was not equipped with a Block Heater? It's installed on every new car I can think of, although it's usually a separate line item in your window sticker (above base price) it's already installed in the vehicle as delivered.

When the Asians first imported vehicles to the Vancouver terminal some did not come with block heaters installed. A few hundred full-engine warranty claims later, that practice stopped about 50 years ago.

Or was your intention to mean you cannot regularly use a block heater where you typically park?

Newer Bimmers use an electric water pump. Could that be part of the problem?
 
Originally Posted By: Johnny2Bad
When the Asians first imported vehicles to the Vancouver terminal some did not come with block heaters installed. A few hundred full-engine warranty claims later, that practice stopped about 50 years ago.



This May be moving to far off topic but can you provide further insight? How does the lack of a block heater result in a full-engine warranty claim? The temperature dropped so low the coolant froze?
 
Originally Posted By: ArcticDriver
Originally Posted By: Johnny2Bad
When the Asians first imported vehicles to the Vancouver terminal some did not come with block heaters installed. A few hundred full-engine warranty claims later, that practice stopped about 50 years ago.



This May be moving to far off topic but can you provide further insight? How does the lack of a block heater result in a full-engine warranty claim? The temperature dropped so low the coolant froze?


Inadequate flow on cold start mainly.
 
Status
Not open for further replies.
Back
Top