Moved a bunch of 1.25" thick plywood Monday, 9 sheets, about 150 feet. Along with a bunch of 2x4's and 2x6's.That was probably the cause. Clean as a whistle.

Getting ready to build some work benches. I've been able to scrounge enough wood from the construction site to build about seven 8'x30" work benches. Looks like I'll wait a few days before any more heavy lifting.