How many of you guys are making it the 100,000 miles on your plugs? I had been experiencing a weird shudder like a miss or tranny not shifting cleanly. I couldn't really tell, it didn't feel like a normal missing engine to me so I thought maybe it was related to the tranny rebuild that I just had done under warranty. I had scheduled it to go to the dealer for diagnosis but flaked on my appointment because I hate dealing with Rams service departments. I'd rather shoot my foot. So I just decided to do a plug change and go from there. Bought factory plugs and tore into it. It turns out the issue was caused by worn plugs, the gap was about 1/4 inch lol on the plugs I pulled out. The van has 105,000 miles of easy use on it. I don't carry very much weight and drive normal. When the service interval is 100,000 miles I usually assume that a conservative estimate. In this case I think 60,000 miles should have been what the recommendation should be. Mine was one of the first pro masters available and I drive more than the normal guy that isn't working out of the van, so I'm wondering if other people are doing plug changes sooner and avoiding this? I wouldn't wait the 100,000 miles, just saying.