toledo

2011 5.0 with 136,000 miles and i haven't had any issues with the truck until recently(wheel bearing, coolant leak at the y,blend door actuator,and i think my rear main just sprung a leak) but with those many miles its expected.. now my attention is turned to the spark plugs.. i have not changed them they are still the original ones but I'm not sure what to change them with.. I've read threads and some say that ford doesn't make the original ones anymore so I'm at a loss. I looked up online at auto zone and they give me options (iridium or plat) but I'm not sure which is best. i know to check the gap on which ever i buy. so should i go with iridium or platinum?

digitaltrucker

I bought SP548 to put in my 5.0 2013.

toledo

just bought them as well.. what did you get them to? .047?

digitaltrucker

I have not installed yet. Rock auto says 051, manual says 049-053 I believe. I was going to check them as I pull them, but was headed towards 048. Think I read that in another post.

digitaltrucker

I just checked the ones I received: they are set at .048, also the box states they are not adjustable.

cbr600rx7

You are good at 0.048. Plugs will open up a little bit over time or about 0.001 every 10,000 miles or so. IMOP it's better to set them a little tight unless you are going for max performance and checking them often. Also prior to 2012 ford had a slightly tighter plug gap.

Ford no longer offers the OEM iridium plugs. However you can get the NGK version for about $8 a plug.

toledo

I installed them and I think they were at .051 out of the box

jlinville

Is that for the 5.0? I just changed mine in my ecoboost with Motorcraft iridium an couple hours ago.

toledo

yes

Cokesda1

Just changed plugs at 160k. Ran perfect with the original plugs. Put in the sp548 as I could not find the 519s. All the old plugs were at .065. New plugs all factory gapped at .049. Might idle just a shade better but not a real noticeable difference.