Quote:
Originally Posted by cookinwitdiesel
Thanks for this - had never considered it. My Mazda CX-9 also has a turbo but I have always treated it like a normal car in terms of start/stop when I get somewhere. Does the engine recirculate the oil that goes through the turbo bearings or are they sealed? Even at idle, the engine is putting out exhaust which will spin the turbo - so is the goal to just let it slow down some before shutting off?
If it matters, watching 2 trips to Home Depot and back over the last couple days, RPMs barely got over 2000 and if they did it was for maybe 5 seconds. Most of the time I was hanging around 1200-1800 RPM ranging from starting from a stop at a light to 65 MPH on freeway. Based on that, I would be inclined to think that the turbo is not spooling up too high? There is so much torque I never need high RPMs and lower gears  |
I know this has been answered previously but the example I gave of pulling into a rest stop after driving highway speeds and stopping and shutting down doesn't equate to "around town" driving. I would guess your trips to HD were not located on the side of the interstate. As previously pointed out driving down the side street, pulling into the parking lot, etc. accomplish the same results as idling for a min. or two. Turbos can spin at upwards of 100,000 rpm. They are powered by the extremely hot (while under load) of the exhaust. The bearing are lubricated and cooled by the engine oil. So, shutting the engine down while these surfaces are very hot can cause the thin film of oil to varnish over. The bearing surfaces of the turbo shaft will score with no oil flow. Some "high end" engines have an electric oil pump and a built in timer to keep the oil circulating for a set time or temperature after shutting the key off. There are kits you can add as well but most folks just let it idle for a few min.
I'd urge as I stated to do some reading, i.e. research. There are tomes written on this site, diesel truck forums, as well as other sites online that can be found with a simple search. You've made a huge investment (at least to the average person's budget thinking) in your new truck it only makes sense to do everything possible to protect it but that choice is yours.
Enjoy your new found joy and take some time during the cold months ahead to snuggle in and do some reading.