Powerstroke "cooldown"

[immrfixit]

New 06 F350 and "edumacating" myself with good diesel care and procedures. I see aftermarket accessory for a "cool down timer" which lets the engine run until a preset temperature is reached. This is supposed to help protect the turbo. Is a cool down idle time needed everytime the engine is run?

[pro99line]

I would say no. The only time this is "really" needed is if you got through really dogging the truck or pulling a really heavy load. You can do the same by just letting the truck idle for some time before shutting it down. I would use the money for something else.

[Andy]

Good question, I've been wondering this myself. Any ideas anyone? I used to live by Everett BTW. I lived in Monroe.

[99Smokin73Stroker]

I hardly ever let mine cool down, unless i've been running it real hard....oftentimes i'll just drive really conservative before I get to my destination to prevent having to sit and let it cool.....

[Keith T]

I have gauges and let my truck cool down until the EGT gets to 350. Keith

[mschn99]

this is just my opinion, nothing based on fact, but the cooling and lube for the turbo is the engine oil. it is not going to change temps and extreme amount once warm no matter what as long as your cooler is functioning properly. basically im thinking that an extended cooldown is only needed if the truck has been run really hard. it is always a good idea on a turbocharged anything to let it run for say....30sec to a minute......but unless youve done something to get the oil temp WAY up....i dont think anything over that, in my opinion....is really needed.

[Rodslinger]

I read something somewhere and Google let me down trying to find it again - BUT as I recall it was written by Banks and he basically said the turbo technology has come a long way and you don't have to let them cool down like in the "old" day's. That being said I normally let mine sit for a few seconds anyway just to get her around 350 like Keith mentioned, or close under 400 anyway.

[Worm Drowner]

From: http://www.bankspower.com/tech_TD-fact-Fiction.cfm

"MYTH #7
You have to let a turbo-diesel idle for two minutes before you shut it off.

FACT
This is a current myth that has a basis of fact stemming from many years ago. It also has a kernel of truth regarding today’s turbocharged gasoline engines that operate at higher peak exhaust temperatures than turbo-diesels. In the early days of turbochargers, the turbo shaft was supported by a babbitt bearing that could seize, or even melt, if the engine was shut off immediately after sustained boost conditions where the turbocharger would “heat soak”. A two minute cool down at idle allowed the turbocharger to dissipate any remaining spinning inertia, and the oil circulation cooled the bearing and prevented oil “coking” in the bearing area. Turbochargers haven’t used babbitt bearings for over 30 years, and today’s oils resist coking. Synthetic oils won’t coke, period. With a turbocharged gas engine, it’s still good insurance to let the engine idle for 30 seconds to a minute to allow the turbo or turbos to dissipate any inertia and to cool the bearing area to prevent oil coking, especially if the engine has been worked hard just prior to shut-down. Of course, using quality synthetic oil eliminates this potential coking problem.

Today’s turbo-diesels are a different story. There is really no reason to “cool down” a turbo-diesel these days, but you won’t hurt anything by doing it either. You can still find people who swear you have to do it, but the myth is fading. Maybe they just like to sit and listen to the radio."


Quite honestly, I always was taught to let it idle down. I always did let my EGT's get down but since I use synthetic oil, I guess I don't have to worry about it.

[Rodslinger]

THAT'S what I was looking for, thanks Michael!

[99Smokin73Stroker]

Good information, very useful. Now I can rest knowing I can go ahead and turn it off when I get to my destinations.