Generally these cars are quiet. They run a little rough at start up in colder weather. Some cam noise (lifters) can happen from time to time, a tick...not so much. It might be nothing, or someone might have put an additive in it and it's got sticky lifters. These engine don't like or need additives ,(I've learned over time.) I had that problem on my 2007 and it eventually went away. Make sure the oil level is where it's supposed to be.
I think the belt you are talking about is for the power steering pump.
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Mine has 36000 and it is relatively silent.
Thanks, BlueAngel#07! I am swearing off engine oil additives now... even before purchasing the car!
Your post led me to research (and search) on the topic of lifters more. I heard the very minor tapping when the engine was cold, and I don't think many miles have been put on the car the past few months, so perhaps it will go away after another test drive and/or oil change? Honestly, the noise was very quiet, especially compared to my wife's '95 4.L. The 4.9L is purty good but it gargles with every acceleration.
Here's one of the posts your comments led me to search for:
http://www.cadillacforums.com/forum...-dirty-lifter-dirty-valve-tapping-sounds.html Everyone's comments from that post helped, plus Submariner409's pictures helped too (thank you!) My understanding now is that a 2011 DTS uses a typical fuel pump back by the tank and typical fuel rails, but no "cold fusion" as suggested by the sales manager.
That's an interesting place to locate a power steering pump. It's all good as long as it works!
