Just a note on all this from someone who has driven turbo diesels for about 20 years. Modern diesels (after early 90's) have not needed the extended turbo cool downs that many claim. I can operate at 70+ mph with gross load of 80,000 lb for a few hours and just by slowing and coasting into a rest area then idling for about 10-15 seconds is enough to cool the turbo. I know this to be fact as I put over 1.4 million miles on my last truck doing it this way and never replaced the turbo nor did an engine overhaul.

The turbo will cool considerably just by coasting, or the time it takes to get down from highway speed, get off the ramp, and drive moderately to where you are stopping. There is hardly any turbo boost driving down the street to get to the gas station or the drive way. A turbo boost gauge will show this. If you get over 20# of boost on a street, you are trying to beat that corvette next to you. Variable vain turbos are a wonderful thing!

If you were to drive for some time at high speed with a heavy load then slam on the brakes and immediately shut off the engine, there might be a problem. But then the problem will probably be not related to the turbo, but to the vehicle that slammed into you.



The old, old turbos used before the 90's did require some attention, but thankfully, those days are gone.

Hmm the GT Cruiser we had for 4 years on I-75 ran 1200 and you would lock the car, go to the restroom
come back and it would just be getting to 800, so get an EGT to know for sure, course that one was gas.
Sometimes with the CRD it does take a moment. I will wait a bit longer.

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2005 Silver Limited CRD 53,000 miles
GDE EcoTune / Trans tune
PML Differential Cover/Crankcase Mod
Tal & Hadas Grill Guard/TransGo Shift Kit
V-6 AirBox/Lunar Boost & EGT
Lund Cold Weather Grill Insert
OEM updated Filter Head, Cummins Lift Pump

My opinion on EGT's :

If you don't want to add any longevity to the life of your turbo, run the pissss out of it and don't worry about any cool down times at shut-off.

If you do want to take care of your vehicle and add some life to the turbo, either install a pre-turbo EGT gauge and wait until 300*F---325*F or idle down based on your driving per the owner's manual.

My CRD has always idled for a minute or so before shut-down; usually a couple of minutes if on a hard run on the interstate. MY 2003 Dodge RAM 2500 CTD idles until the pre-turbo EGT's get below 320*F (I usually wait until 300*F) per the EDGE Juice w/Attitude monitor.

Greg

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2015 Jeep Grand Cherokee Limited 3.6L and A8
*SOLD*2005 Jeep Liberty Limited 4x4 CRD, Bright Silver Metallic, Dk/Lt Slate Gray Leather w/bun warmers, 5 spd auto, 22G pkg, Trailer Tow, 3.73 Rear Axle w/Trac-Lok Differential, P235/70R16 Firestone Destination LE's, Power Sunroof, Selec-Trac 4WD, Infinity 6-Disc In-Dash, Magnaflow #15870 System.

That is a gasser and total different animal, they have higher EGT's and take longer to cool down.

That said I have never done more then what Cowpie mentions for any of my new VW TDI diesels, never had a problem. My old MB diesels from '80's (I-5 with iron head) were never done much different, then came the aluminum heads and all went to hell in a hand basket.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine

I take it the all aluminum block and heads on the new MB 3.0 V-6 diesel doesn't give you that warm fuzzy feeling. I hope they figured out the secret to getting aluminum to take stress cycles without cracking.

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2005 Liberty Sport CRD, Lt Khaki, sunroof

Thankful to now be an EX-CRD owner.

Actually I would feel better with all aluminum or all iron. That said I never had a problem with, and few did, the iron block and aluminum head of the VW TDI engines.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine

Thanks. This is the first I've heard about any need to cool the turbo and reading this thread has been getting me worried that I was killing my CRD by parking it and shutting down just like any gas car. After reading your post I suppose the CRD turbo has been saved by the several minutes of progressively slower driving speeds from the highway into my residential area (45, 40, 35, and 20 mph) which allows it enough time to cool.

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Thanks,
Ken Jennings
2006 KJ Limited 4x4 CRD, Option Pkg G, Lt. Khaki, Built 1 Feb 2006
Tow Package for myself, EVIC TPM
Side Curtain Airbags for my daughter
http://www.kenjennings.cc/crd/dieselexp.html

Ken, if you want even more confirmation, check out this:

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


This is accurate information and is well known in the industry. Myth #7 addresses your concerns. Relax and enjoy!

Here is their quote on the subject.

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.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine

Any time you do heavy city driving or driving at highway speeds your varible geometry turbo or (vgt) is spining at about 20000 rpm the heat from the exhast is spinning the turbo not the exhaust back pressure. So egt temps can get to almost 2000 degrees f. Idling for approx one minute cools the turbo bearing by using 200 deg oil which in turn cools the turbo to around 400deg f. I've been a Caterpillar and Cummins engine tech for almost 8 years now the only diffence between these monsters and the little crd is size

Also if you look in the crd owner manual it even says to cool the turbo down for at least 30sec to a minute. It just helps the longevity of your turbo so u dont end up spending about $1200 dollars for a reman

Can you show me anyone who is running that hard that last minute they are driving down the street to there home, waiting for the garage door to open, and then parking? I know of no one who's driveway is connected to a major interstate highway! Heck, I live in the country, and with slowing down, entering my drive, and then parking, at a minimum I am not applying turbo boost to "spin" up the variable vane turbo in my CRD or my Semi for almost a minute. Unless you are pushing the turbo and then turning the key off, you are cooling the turbo.

Hence.... I have already applied a cool down to the turbo! During the slowdown, the engine oil is circulating faster to cool the turbo faster than any sitting and idling would do. A few seconds extra time to pull in the garage and turn the key off, and you have cooled the turbo! You may have 8 years as a Cat and Cummins tech, but I have over 20 with the same engines, and they were engines I paid for, not just ones others owned and I put a tool to. My last Cummins had over 1.4 million miles w/o an overhaul or major repair, including the turbo.

You dont live in phoenix arizona where it get to 115 in the shade and the asphalt gets to 160f. Ive replaced many turbos that had bearing failures caused by excessive heat. Ive also loaded down 600 hp cats on dyno at 75% load factor and watched the hot side of a turbo turn white hot and see the fins spinning. Now if seeing something like that doesn't give the chills i dont know what will.

There are many, many people in this town that for whatever reason, run full throttle to get in front of you on an interstate exit ramp, blast all the way up it, and immediately turn right into a fuel stop to shut it down. Instead of beating me to the next red light, they beat me to the fuel pump. Dorks.

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'05 CRD Sport born on 06/20/05, bought on 9/23/05, L.O.S.T. on 9/27/05 - modding ever since:

Daystar 2.0" Lift, P255/70R16 Revos, Boulder Bars, Reese Front Hitch w/9k Hooks, Poison Spyder Rock Ring, MOPAR Skids/Bug Shield/Roof Rails/Mats, WARN Hitch Shackle(Rear), 10k Hitch Hook(Front), Custom Tilt/Slope Meter, Ammo Box Mod, Rotella T 5W-40.

But then again there are alot of steering wheel holder out there. But it sound like you know what your are doing. Id rather not take a chance at buying a expensive turbo. I have better thing to waste my money on. HEHE

Yeah tell me about it thats why work from 3:00 pm to 11:30 pm so I dont have to put up with these dorks. Every one out here is in a hurry to stop

No, but since I do drive a semi, I have been thru that region too many times to remember and yet I still do what I have stated about the cool down. I have driven quite regularly in 49 states and all of Canada over the last 20 years. The only reason I would idle longer in your climate would be to keep the cab cool to get some sleep. If I were fueling up or getting I bite to eat, I would just shut it off like normal.

Dyno is not coasting in off of highway speeds, driving down a side street, and pulling in and parking... all of which will cool the turbo down from a working situtation. That is unless you are doing like some and racing the corvette next to you and putting over 20# of boost. There are always exceptions. Most of us don't do that so the turbo will cool just fine the last minute or two of driving.

....and to their surprise, it's not to the same pump. Now they really look like a dork.

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2005 Liberty Sport CRD, Lt Khaki, sunroof

Thankful to now be an EX-CRD owner.

Kind of funny you mention the white hot turbo... as a kid I had an 88 Ford T-bird Turbocoupe and if you pushed it hard driving home at 100+ pushing 8 lbs of boost, and popped the hood when you got home, the turbo was glowing red. At the time it seemed really cool, but looking back I'm amazed I didn't toast that sucker!

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OLD RIDE: 2005 Liberty Sport 4x4 CRD - Inferno Red, Sunroof, Cruise, Tint, Tow Package

NEW RIDE: 2008 Flame Red JK Unlimited X 24S Dual tops, Auto, PW/L, Infinity Sound system, Sirius, Tow pkg, side steps
Added: Black fuel door, 7 pin Trailer lights, uConnect + iPod kit, bikini top, AutoPage 2-way alarm, Flexatrunk

That is why Ford did one thing right and provided automatic cooling after shut off on those 2300 turbo 4 bangers.

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91 MB 300D 2.5L Turbo. Her's

05 MB E320 CDI. Mine