Is there any practical benefit to letting a passenger car oil warm up before driving?

Joined
Jan 20, 2017
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CA
Really, CleanSump is correct. After a career in fleet equipment maintenance and time supervising a heavy equipment engine rebuild shop, the best way to warm up an engine is to give it 15-30 seconds of idle to build oil pressure the put a load on the engine, just drive it easy and use the recommended OEM viscosity.
 
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Jan 2, 2004
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Hmmm, that should not be the case. Exhaust manifolds run super hot. For quicker warm-up usually, heater exchange boxes are used. For example, in BMW coolant line goes through oil filter housing in models without heat exchangers and those with regular radiator coolers.
Newer BMW's have both heat exchangers (to warm up oil faster) and oil cooler radiators.
All Toyota hybrids use some sort of heat recovery system - the 1st/2nd gen Prius uses a Rube Goldberg-esque system of a coolant thermos(think a big Hydro Flask/Yeti bottle), a three-way valve controlled by a stepper motor, a pump and a mess of hoses. The PCM will command the coolant heat storage system to dump warm coolant to pre-temp the engine during start and run the system in bypass mode while the car is moving. When the car is shut down, the CHS pumps hot coolant into the thermos and commands the 3-way valve to shut off the tank.

The 3rd gen Prius and all recent Toyota hybrids uses a exhaust heat recovery system - the cats are plumbed to the cooling system. Now that cats are being stolen off those, the risk of inflicting severe engine damage via overheating if you drive around decatted is real.
 
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All Toyota hybrids use some sort of heat recovery system - the 1st/2nd gen Prius uses a Rube Goldberg-esque system of a coolant thermos(think a big Hydro Flask/Yeti bottle), a three-way valve controlled by a stepper motor, a pump and a mess of hoses. The PCM will command the coolant heat storage system to dump warm coolant to pre-temp the engine during start and run the system in bypass mode while the car is moving. When the car is shut down, the CHS pumps hot coolant into the thermos and commands the 3-way valve to shut off the tank.

The 3rd gen Prius and all recent Toyota hybrids uses a exhaust heat recovery system - the cats are plumbed to the cooling system. Now that cats are being stolen off those, the risk of inflicting severe engine damage via overheating if you drive around decatted is real.
The coolant/exhaust manifold is old trick.
Based on how my V6 Sienna warms up, they need to learn more tricks.
 
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When I get in the car to find the gas light is on, after my wife was the last one to drive it the day before, I have a hard time letting it idle to warm up for her. My wife is BAD about doing that. Sorry, honey. No gas, no idle. Get your frozen tatas in the car, we're going to the gas station.
 
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When I get in the car to find the gas light is on, after my wife was the last one to drive it the day before, I have a hard time letting it idle to warm up for her. My wife is BAD about doing that. Sorry, honey. No gas, no idle. Get your frozen tatas in the car, we're going to the gas station.
I noticed that my Tiguan if the low fuel indicator is on it will shut itself off after a remote start. Machine-imposed "no gas, no idle".
 
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I'll guess my car idles for about a minute upon cold start before I get going. If the whole herd it's going somewhere, it can easily idle 2-3mins as 1 kid always gets in a fight (& loses) with the seat belt.
 
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I found the oil is not the target to warm up but the pistons are. The pistons need to expand to operating temperature. So the piston rings can seal and piston slap does not occur. It is the metal in your engine that needs to expand.

 
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I found the oil is not the target to warm up but the pistons are. The pistons need to expand to operating temperature. So the piston rings can seal and piston slap does not occur. It is the metal in your engine that needs to expand.


He also stated it only takes a couple of minutes to reach an ideal point and idling longer than that can be "too much of a good thing." Another thing is most OEM aluminum engines are cast aluminum, most with hypereutectic cast pistons, which don't have thermal expansion of forged aluminum which is why forged pistons, like you'd see in a NASCAR engine, need wider piston to wall clearances.
 
Joined
Oct 10, 2021
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Wisconsin
I live in wisconsin. I might let a car warm up 30 seconds. But slowly driving it with little force is a better warm up when its 30 degrees and more.
However I have lived thru minus 26 F temps just a couple times. The noise your engine and trans makes at those temps makes you cringe. At that temp I ran the engine 2 to 3 min and slowly drove a while.

I talked to my toyota master mechanic about warm up and he said generally 15 sec of run and drive slowly a few minutes is great.. BUT the transmission more than the engine might do better long term with a 30 second to minute warm up. Super terrible cold might be better served with a couple minutes of trans warm up. But those are only in fairly extreme conditions.
Lately here in wisconsin its been 10 to 16 degrees. When I start my v8 sequoia I do let it run 20 to 45 seconds to start to get some fluid moving around the inside of the trans. It seems to shift a bit hard the first 2 or 3 minutes. Not terrible. But more clunky than at op temp or above 30 degrees.
 
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An interesting thing is to take a half full quart of oil at ten degrees and try and slosh it around. Its not solid. But its sure no very easy to pour. A typical engine with 6 or 6 quarts of oil and 3.5 gallons of coolant and 350 pounds of metal mass takes a long long time to get to op temp.

Any other people here with an oil temp guage ? Even at 40 degrees out it can easily take ten to 15 minutes of driving to get your oil to a temp I would ever rev the engine much.

Just because you have marginal heat from hot water does not mean your oil is close to hot.

For fun. Take your 15 degree car and run it a minute then change oil. It will make you a believer that oil does not get much heat quickly
 
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Jan 7, 2022
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Chicago
My 07 Acura tl idles **** during winter starts. It retards the timing and ignition so the motor warms up quicker...the idle stays at 1000 but the engine shakes whereas my infinity G37 tags 1400 and slowly drops to a 1000 like most other cars and the idle is just fine.

Acura even states in the manual a rough idle during cold startups is normal.

So you can't really drive the Acura until the idle smoothes out
 
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Jan 7, 2022
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People get too myopic about engine warmup when the trans and differential oils are more important in my opinion. My G37 AWD when I put it in neutral before the diff oil is warm will slow me down like I drove thru deep water...so I have to drive around a couple blocks till the lousy supertech gear oil,which I'm draining in August for something better, warms up so I don't feel a drag or blow out my axle seals.
 
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People get too myopic about engine warmup when the trans and differential oils are more important in my opinion. My G37 AWD when I put it in neutral before the diff oil is warm will slow me down like I drove thru deep water...so I have to drive around a couple blocks till the lousy supertech gear oil,which I'm draining in August for something better, warms up so I don't feel a drag or blow out my axle seals.
Hmm. How is it “lousy”? And if it’s that bad why wait till August?
 
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