everyone should let their CTD cool off after running it...mine after a substantial highway running, not particularly loaded, is running three hundred degrees in about twenty seconds of idling. i let it run a few minutes longer just because of what i have been reading.

the tuner in my area told me to let it idle down to about four hundred degrees before shut down. my truck never runs that hot for that long.

any input?

thanks

 

I've read that 300 pre-turbo is the accepted number for serious gauge watchers. My probe is post turbo and only goes down to 300, so I wait till it drops off the scale and then shut her down.

greg

 

I used to shut down about 350* but my PSD always ran hot cause of my PS2000 and my 130chip. BUt with 4" strait pipe ending b4 the wheels it didnt take long to cool.

 

Yall worry to much. I've never let mine cool down and I've got 78k+ miles on it. The only time I let it cool down is when I park and roll the windows up. Once the windows are up, it gets turned off. Turbo still spins just as freely as it did the day I bought it.

 

with a scooter II and afull 5'' pipes, its at 230-250 almost instantaneous. now should i give it a few seconds to be safe or no big deal.

 

jj3500,

i had the 6 speed as well and whenever i was coming to a stop (whether just a traffic light or a pit stop at the local station) i always downshifted. the egt's dropped really fast and as long as it was around the 300-400* range i shut it down, with a few 450* in there. i had no problems to speak off, turbo was still tight at 115000 miles.

Pat

 

I no longer wait for the turbo to cooldown ........ http://store.dieseltruckresource.com/hoco.html

 

Do you really?And u havent had any trouble yet? hmmm now its got me thinking if we really need to...My dad always said u dont need to with the way the oil is now adays. But i always did.

 

120K here no cooloff before shutdown......Im with BigBlue on this one.......

I think if youve been runnin extended periods of hours down the freeway at 80 mph than u might wanna let it cool for a sec..but otherwise forget about it......

If it does break which mine has not..its just a reason to get a better hybrid turbo....or twins

 

My dad, and uncles never let theirs cool down before shutting them off with no problems. I personally like to wait till at least 350* before shutting down, but i dont think it hurts anything to just shut them down.

Eric

 

I have no hard evidence...and therefore no real idea how prone a turbo is to coking oil problems.

I do know what the average non synthetic engine oil looks like when it's been heated to 450-500* and allowed to "soak" at that temp for a while, which is what some of you are doing! FYI, the "flash point" of many oils is in the 400-450* range.
Easy to test....just cook some oil with a candy thermometer in it to measure temps..hold that temp for 5 min and see how it looks, feels & smells.
I don't want that oil circulating through my engine for another 5,000 miles.

RJ

 

I let mine cool down to about 250 on mine it has 122k on it and no turbo issues . Other than the hx35 is just to small and i want a bigger one

 

230k miles, original turbo. I bought the truck with 215k on it. I can guarantee that the PO didn't idle very long after driving it... turbo spins freely... and runs 35psi.

Cummins says not to bother idling unless you're towing or coming from high speeds...

Think for a moment about the EGT's on a turbo gasoline engine... yeah...thought so.

 

But Holset says you should let it cool down.They have a graph on their website showing the proper idle times.I don't know but it seems like it is good for all the other oil lubed parts in the engine as well as the turbo to cool a bit.