It most certainly does. Viscous shear in the bearings is the primary source of heating in the oil.
Viscosity Grade recommendation for Death Valley
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Well, I have data logged quite a few vehicles, the results are as follows, starting a cold engine in cold weather, with the vehicle just sitting there receding to 1500 RPM, it barely heats up. Starting the car and driving the vehicle heats up the engine fast bc you are putting load on the engine. If you are driving along and the engine temp is 194 and you full throttle the car, the engine temp comes down to about 183. RPM moves fluid causing a cooling effect. It’s the same as transmission fluid. If your chugging along towing at 2000 RPMS climbing a light grade, trans temp will start coming up, downshift one gear get more rom and it moves transmission fluid, cooling it.
Engine temperature and oil temperature not the same thing. Engines are heated up by other things including piston ring friction.
And as for your transmission your logic is faulty there as well for other reasons.
We’ve had lots of discussions on this here. Perhaps you have missed them. Several technical papers have been presented showing how shear heating is the primary source of heat in the engine oil. It’s also why if you wish for your oil to heat up faster in cold weather you drive at a moderately high RPM and use a more viscous oil.
This was one of user @Shannow favorite topics. I thought the same thing you did but learned that I was incorrect.
And as for your transmission your logic is faulty there as well for other reasons.
We’ve had lots of discussions on this here. Perhaps you have missed them. Several technical papers have been presented showing how shear heating is the primary source of heat in the engine oil. It’s also why if you wish for your oil to heat up faster in cold weather you drive at a moderately high RPM and use a more viscous oil.
This was one of user @Shannow favorite topics. I thought the same thing you did but learned that I was incorrect.
I agree, and in fact I have seen this on scanner. 100% true.
Heat and load correlate and one causes the other. RPMS are irrelevant
Agreed. I recommend crunchy peanut butter in case a bit of extra grip is needed
Not true. It sounds plausible but it’s not correct. RPM has a large influence on heating in the oil.
https://bobistheoilguy.com/forums/t...ine-heat-and-effects-of-oil-viscosity.297737/
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The transmission and coolant absolutely cool down by moving more fluid. Your turning the pumps faster moving fluid faster through the coolers. I watch this happen on my super duty towing my 15,000 pound grand design solitude. If I am on flat ground, my oil temp runs about 208-215, transmission is 199 engine temp 194 engine is turning 1550 rpm. If I climb a grade and the truck stays in 6th gear which in most cases it does, the oil temp goes to 220-230, trans temp goes to 208, engine temp goes to 203. If I put the truck in fifth gear all the fluid temps come down to normal bc the truck is now turning 2500 rpm moving fluid faster as the pumps are moving more volume. This is real world not assumption that your saying. And that is why your supposed to tow in your 1:1 gear ratio gear for cooling purposes and power. Like I said I have data logged many vehicles as I am a tech.
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Dude, why do you think engines cool down as you sit and idle in park. It’s called no load on engine. That’s why they cool down.
Yes they certainly do. Where did you get the notion that I said something different?
What generates heat?
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I see it with my own 2 eyes on dealer scanners. You’re wrong, hence the reason cars never heat up in winter just sitting and idling. When you drive it, the load causes heat and pressure.
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He thinks RPM generates it but adding RPM has a cooling effect. I’ve seen it in scan tool as well on Honda accords with the 6speed manual and CVT. The 6 speed manual turns 2400 rpm at 70 mph and the CVT turns 2000 rpm at 70. The engine runs cooler on the 6 speed bc of the 400 additional rpm turning the water pump moving more water through coolers.
yeah......and the fans are moving faster......and so on........
but in this instance, you are allowing the energy of the engine to leave the closed system easier and pull the load, through gearing.
energy only changes it is not created or destroyed.........the heat that builds up is energy put into the drivetrain (in this case).....because of the load on the system.
Was it the scary graphs that have you flustered?
Nonsense, otherwise the cold start cycle would not give everyone a high idle. It's simple physics, spinning faster will lead to higher frictional losses.
Ultimately, every bit of heat in the engine comes from the combustion. But combustion temperatures is not the primary source of heat in the engine oil. And even if you struggle with that notion, RPM is not “ irrelevant” as you postulated.
I’ll place all of this in the same bin as the multi-page argument you made about LSPI.
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Yep My truck has one big viscus clutch fan belt driven. When I had my 2004 nissan titan, I had a bumper pull travel trailer, weighing 7000 lbs, on the same grade that I explained earlier with my super duty, I wouldn’t tow in fifth gear so that truck turned 2500 rpm as well bc if you towed in overdrive, the temps would come up and it would gear hunt. So I would turn off overdrive climbing those grades in the titan and the fluid temps stayed the same.
Yes. And it’s why transmission upshift is often inhibited on a cold start.
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You just showed me you don’t know why engines idle high on cold start. They idle high bc of the amount of fuel that is injected in to the cold engine and it needs RPM to burn off or the engine would hesitate and run rough.
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