What are the advantages of an oil cooler?

obi_waynne

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I know a few of us have them so what would you say the advantages are in having an oil cooler?

Do you view it as something to prolong the life of your engine or have you noticed performance gains?
 
Sorry - being silly today. An oil cooler is clearly no use during engine warm up and does slow down that process. Some have thermostatic bypass valves to help this. Turbochargers do put a lot of thermal stress on engine oil, so coolers are helpful here.

It's not a case of the hotter the better, there is an optimum temperature for oil in an engine.
 
:lol: Really ? :blink: Hot oil is thinner and flows better though?

True, but also as a result of lower viscosity has lower lubricating and protection abilities ( as does old / dirty oil )

Oil coolers are generally fitted or needed in high stress engines, highly tuned, automatic etc, they all should have a thermostatic valve to regulate temp.
Most modern engines and oils are so well engineered that coolers really arent needed unless you really go to town with your tuning or race where the engine is working at extremes for long periods!

However the exception to this is minis ( propper ones :blink1: ) where the engine and gearbox share the same oil, coolers were always a good idea on all but totally standard ones.
 
However the exception to this is minis ( propper ones ) where the engine and gearbox share the same oil, coolers were always a good idea on all but totally standard ones.

Yeah, I'd forgotten about those. Did the very rare automatic ones use engine oil for transmission as well?
 
I'm surprised more car makers are not fitting these as standard then, especially with the high power outputs and increasing use of turbochargers.
 
The RS6 has an oil cooler from factory and I must say it does a mighty good job at keeping oil temperatures sensible. Even on the dyno oil temperature barely peaks above 105c. The C63 I had before was a regular for 115-120c oil temperature just from spirited driving on the road.
 
I did. Was a fantastic car to drive, and the noise was epic... but my god was it plagued with issues. Mercedes ended up replacing the whole car in the end, and even the replacement had trouble. Annoyingly I've tuned 30+ of them now, and nobody else has had any problems. I think I was just destined not to own one for very long.

The first car suffered electric steering column motor failure, wing mirror folding getting stuck and then something bottom end on the engine went at 19k miles and it smashed the valve train up.

The replacement car suffered immobiliser problems, and kept refusing to start. The power steering pump went faulty and started sounding like a supercharger. The front nearside wheel bearing started making horrible noises. The traction control kept coming up with a fault everytime it kicked in (which was frequently on a 487hp RWD car) and then I gave up when something went wrong with the hydraulic lifters and it started sounding very 'happy'.

c63-amg-9.jpg


This was my C63 outside work on one of the very rare occasions it wasn't stuck in the Mercedes dealership!!
 
Some cars have either the engine or transmission oil lines pass thru the radiator end tanks for cooling BUT there are many stories about them failing so If any vehicle of mine had that type of OC one of the first things to do would be to cap off the lines entering and exiting the radiator and fit an external multi row oil cooler that would be far more effective.

IMO the bean counters overruled the engineers to save a $ or 2. \B
 

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