I've read a lot on here about cool down periods. Assuming I'm not pulling or hauling anything but just driving without a load, how long should I wait for the turbo to cool down? I don't have any gauges besides the factory ones. The manual recommends 30 seconds for no load. What do y'all think?

 

I would say the owner's manual is pretty good as a rule of thumb. Having the pyrometer takes out some guess work, but most of the stock trucks I've seen have pretty much borne out the manual for cool down times with a little safety factor built in. FWIW.

 

Does the cool down period have anything to do with the distance you travel or just the load you've got? For instance...if I drive 500 miles at 70 mph or drive across town to get a Slurpee do I still allow a 30 second cool down if I didn't have a load??

 

[quote author=Hoss link=board=20;threadid=15173;start=0#142532 date=1054050532]<br>Does the cool down period have anything to do with the distance you travel or just the load you've got? For instance...if I drive 500 miles at 70 mph or drive across town to get a Slurpee do I still allow a 30 second cool down if I didn't have a load??<br>[/quote]<br><br>Yes, it does have something to do with how hard you've been working it. If I recall correctly, they have a little chart that says &quot;No load around town 30 to 60 seconds; No load highway cruising 60 seconds to 2 minutes; medium load 3 - 4 minutes; heavy load operation 4 - 5 minutes&quot;. It is a function of how much heat you have managed to build up in the turbo housing and in the cylinders. Harder work equals more heat, ergo more cool down needed.

 

Thanks Gramps....I knew you'd have the answer. Now go over to my cold starting thread and educate me on that one.

 

Hoss,<br><br>Here is the cool down times for turbocharger from 2003 Ram Service Manual page 11-13:<br><br>TURBOCHARGER (COOL DOWN( CHART<br>Driving / Load / Turbocharger/ Idle Minutes / <br>Condition / /Tempperature/ Before ShutDown/<br><br>Stop &amp; Go / Empty Cool / Less than 1 /<br><br>Stop &amp; Go / Medium / Warm / 1 /<br><br>Highway / Medium / Warm / 2 / <br>Speeds <br><br>City Traffic/MaxGCWR/ Warm / 3 /<br><br>Highway /MaxGCWR/ Warm / 4 /<br>Speeds <br><br>Uphill /MaxGCWR/ Hot / 5 /<br>Grade <br><br><br><br>

 

First I installed an EGT gauge on my truck. Then I realized I was turning the truck off to soon. Next I installed a diesel turbo life saver because I didn't want to have to wait for the darn thing to cool down enough for safe shutdown. <br><br>Now I have a question for all you long time diesel owners. I have been talking to the other guys at work who drive diesels about the cool down time. They have been laughing me right out of the shop for concerning myself with the cooldown time. I know what I have read in my manual but I still have to ask:<br><br>Is it really necessay to wait until 300 degree EGT before shutdown.

 

I understand the need for heat dissipation, but what exactly can happen to your turbo if you don't obey the cooldown periods? My wife has been driving my Ram to and from work on a daily basis and around town on the weekends, and she doesn't wait for a cooldown. When I tow her horses around, I always wait at least 2 minutes. I have some gauges on order, should be here this weekend.<br>

 

The cooldown issue is primarily required when you are loaded. Driving around town empty is usually not a problem. Under load the turbo charger becomes very hot. Allowing the cool down period allows the oil to remove heat from the turbo bearings. Shutting down too early cooks the oil and crystalizes or &quot;cokes&quot; the oil and eventually will result in turbo bearing failure.<br><br>Interestly, we operate a fleet of 40 ambulances with Powerstroke engines that operate close to max gross weight most of the time; they are run hard and shut down often withour regard to a cool down period and we seldom have encountered a turbo problem. FWIW<br><br>Casey

 

The chance of that type of coking problem is greatly reduced with the use of synthetic oil.

 

Lightman beat me to the punch on that one...synthetic oil will not coke like regular dino oil will.