Hello, I have got a 08 KW T800 with a CAT C15, a SDP engine. Has the DPF and the twin turbo setup. My problem is when you shut the truck off the low pressure turbo sounds like it has dry ball bearings. This is the second turbo I put on it, an used one with 150,000 mi on it, the original one was making the same noise. When it is running or pulling a load you can't hear it so...? Should I just run it? P.S. It does have some play in it. I need answers soon!
It's fine....CAT used ball bearing turbos in the EPA '07 engines and yes they are noisy while spinning down afyer engine is shut off. Consequently they also have much more play in the shaft compared to what you're used to feeling on other models. All sounds normal and nothing to be concerned with.
OK, I'll take your word for it. Still bugs me why it should be noisy. When we got the turbo it was perfectly fine although it sat a the shelf for 6 months.
I worked for a CAT dealer when these came out and there was an Information Release stating the above and not to condemn them because shaft felt "loose". With ball bearings, once oil pressure is no longer centering everything up the shaft becomes sloppy and bearing gets noisy.
These low pressure turbos do have ball bearings right, so oil pressure is not a necessity, am I wrong?
