Thanks , just got back from Napa I just need the proper size. By the way , they don,t carry Motorcraft glow plugs. The truck "expert" working the counter explained to me that the autolite and motorcraft glow plugs are identical..Madfe in the same factory same materials same specs ....just put in a different box. I find that hard to believe after reading this forum for a few years. I would love to go back and give him some undenialable proof. Maybe Ill bring in a few of the motorcraft gp's once I track them down. Heading out now to but a new block heater and new glow plugs and will try to get them in before Christmas. thanks for your help.