I had my engine light come on this weekend so I dropped it off at dealer this morning. He called me up and said my turbo was stuck and did not go into alot of detail other than a lack of driving it or short trips may have caused it. I told him I don't drive it a tone, but when I do I exercise the turbo like I've read on here. Had my wife pick up truck, I'm out of town working. Sounds like they had to pull the turbo and pull it apart from the service invoice they gave her. Should this be a big concern? It did sit alot last winter, but I used it quite a bit this summer, even pulling a 6,000# trailer a couple time for 300-400 miles. Is there any thing else I should be doing?

 

Do you idle the truck after driving it? This will help cool down the turbo and prevent coking.

 

No, I have never let the truck idle after driving it. I thought a read awhile ago that it was not really necessary.

 

I don't know who said that, but for an oil cooled turbo, if you shut it down before letting the turbo cool down the oil will stop flowing and essentially burn the oil thats in turbo.

 

Yes you can "coke" (burn) the oil in the common shaft bearing between the turbine & compressor wheels on a turbo if you run high EGT for long periods of time, do to towing etc. Under normal driving conditions this is not a problem with modern engine oils. If you are pulling on the highway for long periods of time, then when you pull off at a rest stop or fuel stop, letting the engine idle for about 5 minutes will allow the EGT & Turbo temps to drop to safe levels before turning off the engine. This will prevent any premature wear on the common shaft bearing.

As far as deposits on the VGT vanes, these are caused by impurities and moisture in the exhaust and only occur on the exhaust side of the turbo (turbine blades), these deposits can cause the turbine vanes to stick. This problem is most commonly seen in 6.0's that are only driven for short trips, parked for long periods of time or run poor grades of fuel.

The VGT turbo is not "oil cooled" the oil does provide lubrication to the common shaft bearings, but the main use of oil in the VGT turbo is to control the position of the turbine vanes. The VGT is hydrualically actuated using pressurized engine lube oil, by the VGT acutator piston. The actuator piston postion is controlled by the VGT actuator solenoid and the VGT actuator solenoid is commanded electrically by the PCM.

 

Is that how it's possible to use a VGT turbo as an exhaust brake?

 

Yep, through custom tuning of the PCM (ie Matt at Spartan or Eric at Innovative) just command the VGT to close down and you create and exhaust brake.