Today in MA it was 20F/-18C, and on the way to the gym before dawn, I got a pretty loud and harsh sound coming from the driveline (at least it sounded and felt like the driveline). It was the first time I drove this vehicle in weather that cold.

I had driven about a mile before the noise happened.

Pulled over, crawled around, but didn't see anything. Forwards, reverse, and then 4WD in both directions. Nothing. Continued driving and in about half a mile the noise started again while going down a small hill.

On the way back from the gym, it happened twice more, sounding more and more like the driveshaft was binding.

Once home, I checked the driveshaft zerks and the joints looked dry. (I've owned the car less than a year.) The u-joints got greased until the grease started to ooze out the joint, but the slip yokes both took 15 pumps without anything coming out or any visible swelling - what some online sources recommend.

I took the zerks off, bounced the truck up and down as much as I could (I just rebuilt the suspension and installed 5100s), but nothing came out of the hole.

No noise driving after the greasing, but it was 35F/2C.

- What else should I look for that could create that kind of noise?

- If the slip yokes are not supposed to take that much grease, where is it going?

- Who else is spending the last work day before Christmas break on the forums?

Thanks to anyone with ideas!

2010 4WD SR5 with 177K