Hey guys, first post here. I have a 2008 Canyon with I5. A few days ago the temp around here dropped to 3*. Started the truck with no issues and never saw a problem. Drove about 25 miles and parked for 2 hrs. , moved the truck to use another car when I noticed a lot of oil drips in the gravel about the same areas as the cross members. Looked under the truck and it was covered in oil. Next day temp was around 40* and after a closer look it seemed to come from the bell housing, the front, top, back and sides of the engine were clean. Removed the bell housing plugs (2) and looked inside with a mirror best I could and found there was oil inside the housing but could not tell from where. Cleaned the area with brake clean and started the engine (after adding 3 quarts of oil to get it back full) did not see any more oil leaking. Drove it 14 miles and lost no oil and saw no drips or leaks from the housing. Sprayed the bottom of the truck at the car wash to get the oil off it. Since then have drove a total of 250 miles with no oil lose or drips. I read about 2 other Canyons with this same issue below 10*. They took it to the shop and the mechanic found nothing. A GM on line tech responded that the seal most likely shrunk while cold letting oil by, when warmed back up it was not visible. Any body ever have or hear of this. The local GM dealer mechanic/techs have never heard or seen an I5 with a bad rear main seal.