Hi George, im new here but spent the last 15 years groing up next to a junkyard. I had to buy glow plugs for my 1983 ford f350 6.9 diesel about a year ago. I got the autolites from advanced auto(used to be track auto). They were verry reasonably priced and had a 2 year warranty. This was the only parts store I found with warrentied glow plugs!!! They were something like 8$ a pop special order and got there 2 or 3 days. I asked about glow plugs for my 1981 Isuzu 1.8 diesel, same warranty, same special order but I think the price was up around 11$ a plug. The warrenty is the way to go in my opinion that way if something else is wrong and glow plugs fry you just have to change them again. I didnt want to buy a second set of 8! good luck. Lyle