DennisB DenLorsTools.com © Summary: GM only authorizes one thread repair company for their aluminum blocks – Time Sert. Over the years Time Sert has worked together with GM’s engineers to design only the best quality thread repair kits in the business. That’s why Chevrolet only approves Time Sert for thread repairs in their aluminum blocks. Best of all Time Sert Kits are made in the USA. Read the rest…