Just replaced my T-Stat at 110K miles. It probably needed changing sooner. The DIY instructions were a major help. Ended up taking the radiator out to help with EGR flange bolt reinstall. I also tied a piece sewing thread around the flange bolts, so when I dropped them, they could be easily retrieved (use to do this in the Air Force. Dropping a screw/bolt down a vertical stab would cause two days of maintenance).