Originally Posted By: thorromig
Installed Bosh Platinum 2s on my Explorer at 55 thousand miles. At 97 thousand it has been idleing rough and MPGs have dropped. Now that the weather has broken some here where I live, gonna put Motorcraft Platinums in and hope to smoothe out the idle & return MPGs--wishful thinking!!
Not wishful thinking at all. Our Mountaineer needed new plugs at 50k miles, and now were at 107k and they are needed again. It seems the 4.0 SOCH starts to have issues every 50k, like when it is first started in the morning it will go to high idle and then drop down to almost stalling for 3 seconds and then slowly climb back up to fast idle. This problem immediately goes away with new plugs. I won't be doing them though because we are selling it in a couple of months.
On second though, who am I kidding? I'll be replacing them because I just can't help myself! I went with Autolite double platinum last time, but maybe I'll go with the cheapest ones since we will be sending it on its way at some point.