I purchased the purple cranium half spyder to install on my diff. Got all ready saturday morning started removing the 13mm bolts and I got to the 6th one( the last of course) and bam! Sucker is frozen. Now this is a new truck with less than 5000 miles so I was a bit suprised! Got my trusty hammer and adjustable wrench and started pounding without any luck. I am afraid to round off the bolt. I have purchase a bolt extractor socket and will try heating up the bolt then spray a little WD40 then try the bolt extractor. Now keep in mind I am on a creeper under the truck with hand tools. I don't want to have to pay someone to put it on a rack and remove with an air wrench but this is about my last option. You folks have any suggestions and tricks you have tried. I don't want to round off the bolt if I can help it or I am then stuck taking it somewhere to be removed. All this crap for such a simple process.