Yesterday it was very cold the high for the day was 12 degrees F but over it dipped to 10 below zero F. When I started my car yesterday it kick right over. I let it sit for a few minutes in these temps. It did stall once but restarted immediately. When I back out of my driveway and started driving, at slow speed as my streets and most of the streets around here are either snow or ice covered. As I was driving a whistling noise started in the car, and it was tuned with the engine, that is as I went faster it got louder and when I slowed it got softer and stopped when I stopped. This went on for a good 5 minutes plus and finally stopped. Today it was 24 above Balmy. When I left the house the car started this noise again, but low volume and it only lasted about 2 minutes. Any idea what this might be?

 

Best guess is the prop shaft center bearing. Just based upon the sudden onset and being cold temperature related combined with the "stopped when I stopped". Search "prop shaft" and see if your noise is described in the many threads.

 

Hey Adam, for about 2 weeks after I swapped out the transfer case fluids I got a weird kind of howl only in the lower gears at under 15K or so. After the initial week or so it went away and never came back. But if the grease in the driveshaft bearing is not rated at below freezing it will likely make a howl as well, my Discover did that, it was a greasable bearing so I took it to a lube shop and they put in winter rated grease and it went away. Not sure whether our bearings are greasable, being a Jag it's probably lubed for life or something.

 

The weather has been much milder and the noise has not re-appeared. So I am going to see when it temps drop down to the -5 to +32 degree area if it starts up again. I am leaving in a few minutes to a the VA Hospital for my semi yearly physical and I'll see if it makes any strange noises. Thanks as always for the advice. You guys are a wealth of info and I appreciate you responses very much.