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What wattage oil pan heater do you guys recommend me?

I’m looking at getting an oil pan heater on a 2009 BMW M3 because the oil in there is some 10w-60 and it can get down to -25c where I live.

The car has around 8.5 litters of 10w-60. The purpose of the oil pan heater is not to use it overnight, as I don’t DD the car. It will be more when going out in winter with friends I would like to plug the heater in maybe1 hour or 2 before going out just so the oil flows better at start.

I was thinking a 250w heater like this but not sure if it’s enough.

I don’t think 2 hours use of a block heater will make much difference. I am having trouble understanding why you have 10w-60 oil. What does your manual call for?

It’s not a block heater, it’s an oil pan heater. I believe a block heater heats more the coolant and the block rather than the oil pan. Unless I’m wrong.

10w-60 is what’s in the manual and what the car comes with stock.

That heater says to apply to flat aluminum surfaces only.
All the oil pans I have had are either flat steel or ribbed aluminum.
If the car is parked outside at -25, 250 watts won’t do much if there is any wind.

Living in North Dakota in -40 real temp, my remembrances are the dipstick heater will fry your oil, the magnetic oil pan heaters are worthless, the 450watt inline coolant heaters are a waste of money, the only solid reliable thing up there was a block heater, and the parking lot for my work and apartment had outlets to plug them into.

The oil pans are aluminium and look like this

So 250w isn’t enough at all?

But my goal isn’t to heat up the block to make the car start easier it’s just to make sure the oil isn’t super cold to avoid premature wear. 10w-60 doesn’t flow really well at all when very cold.

You totally do not get the concept of sub zero temps. Sure the oil might be warm, but when it goes to a sub 0 block, that is minimal gain. the block heater for a few hundred watts warms the engine, an inline hose heater throws much of the heat out of the radiator, the oil pan heater keeps the oil warm nothing else, I am sorry but you go live up nort there hey and see there are only noobs trying an oil pan heater, convince yourself of whatever,.

Yeah but that’s my point, I don’t need the pros of the block heater. I do live north, I live in Ottawa Canada. Our average cold temps are colder than in North Dakota.

There’s a common issue with the S65 engine in the BMW M3 with rod bearings that has tight clearances and causes premature wear. Heating of the oil will allow it to flow much easier. I don’t know if you know but 10w-60 doesn’t flow well at all when cold.

If I’m totally miss understanding this explain but my point here is to get the oil warm and not cold.

Instead of soliciting opinions from a generic web site try a BMW based forum or even better talk to a BMW service shop. They will have much more experience with the Canada climate. I suspect you bought this used so it very likely to have been started in cold temps many times before you owned it.

Well I figured it’s a generic oil pan heater. The same formula applies on how many wattage is needed per litre of oil based on the weight.

Yes but I wanted to take extra steps so avoid even more wear. The usual thing it to let it idle 45 seconds after start and drive it not hard. The redline locks at around 5k I believe and then when the oil temps hit operating temp it unlocks to it’s full 8400 redline.

I mean, I guess I’m overthinking it but I really wanna baby it as much as I can.

Bingo ! We have a winner.


“What wattage oil pan heater do you guys recommend me?” - OP

I don’t. I was stationed in North Dakota for three years, and I recommend either a block heater or a lower radiator hose heater. Both will heat the coolant and the warmed coolant will circulate through the engine via convection. The oil will not circulate. I learned during those years that oil heaters are useless.

I had a lower hose heater, and it worked great, even during those not-uncommon -40F nights.

Is your point of oil heaters bad because they simply don’t work to heat the oil or your point is that heated oil doesn’t do anything.

Here’s the proof :slight_smile:

My point is that they only warm the oil in the pan and not the engine. And by the time the oil gets to the pump, it’s lost any warmth it was given by the oil heater. They’re only very minimally helpful if at all. Heaters that heat the coolant are the way to go. They warm the entire engine via the coolant.

Having lived in North Dakota was an education in more ways than one.

But that’s exactly what I need, oil that flows better. The engine that is in the car (codename S65) has very tight bearings clearances. With 10w-60 oil, we all know it flows really bad when it’s cold, talking abouit winter temps. So if I can heat up the oil before the engine is satrted, the oil can lubricate the bearings much easier. I’m trying to avoid having a lack of lubrication in these bearings.

That said, I still don’t think I will be getting it. I’ll just deal with it and replace the bearings like most people are doing to the upgraded ones.

EDIT: Ah, so they loose the temp when it hits the pump.

In my previous post with screen shot of the oil specifications, the paragraph below noted: “if the vehicle is operated at temperature below -4 F/-20 C for extended periods, your BMW center will be glad to recommend an optimal oil”

Have you tried contacting your local BMW dealer with this inquiry? They can probably give you the best advice.

Yup, I’m not going to argue but just spend the $100 and have a block heater installed. When you buy the cold weather package on a car, you get a block heater and it heats the coolant which also warms the oil. That is all that I ever used in Minnesota and South Dakota except a dip stick heater for my air cooled VW. The factory knows what they are doing. I’m not going to say any more and the advice is free so no refund.

No I haven’t, but on the M3 forums someone said they did and they mentionned to use 10w-60 all year round.