Spark plug service

I’m at about 74,000 miles. They claim plug service is due at 60,000 from what I can find on the net. A plug and coil pack service runs $500 give or take a few bucks in my area. Has anyone here had this service completed and if so at what mileage? How did the plugs look?

I would have thought they’d be good for 100,000 miles but a mechanic I am not.

I have been reading on the subject. The overwhelming bulk of the comments are negative. While the service manual states 60,000 miles for spark plugs, owners are experiencing complications caused by the plug construction,  seized threads,  corrosion, and thread frailties.
Talk to an experienced mechanic and get his opinion.

I contacted Ford dealer and the mech who has worked on my rig. They say 105,000 miles per the manual.  I have no idea what’s right or wrong

This is stated on the bottom of page 242 of my 2007 owners manual.

"footnote 3:
For spark plug replacement, see your authorized dealer. Refer to
scheduled maintenance information for the appropriate intervals for
changing the spark plugs."

I suspect the motorhome application of the E350 and E450 chassis will be considered "excessive" compared to an E150, E250, or E350 van with the same engine.  I would call your area Ford service center and "GIVE THEM YOUR CHASSIS VIN" and tell them the chassis is a motorhome.  They just might say 60,000 mile intervals because of that.

They do similar deviations on cars used as taxi cabs and such.  Service intervals are tightened up.

When I think of the high rev'ing our V10 engine goes through, it leaves me to think "sooner at 60,000" rather than later at "100,000" miles, but when our chassis hits 60,000 miles, I will first call my area service center and get the scoop on spark plug intervals.

Regarding spark plug problems mentioned by Taildragger, he is correct, there were problems.  But they were resolved around 2003.  That is long past for nearly everyone on this forum.  The few of us with such an old PC, just be mindful that a mechanic might experience some trouble, charging you more for the job.  My brother has one of the earliest V10 engines in his 1998 motorhome.  He had his spark plugs replaced a couple of years ago which went just fine.

Personally, I will be changing the spark plugs myself, when it comes time.

Update.   Now at 83,xxx. Miles and runs good but decided to have the service done. Called three places. Two small businesses and Fords quick lane.  All the same price.  3 years ago plugs and boots was $550.   Now it’s $898. But as the day inflation is now under control.   Nuts but after shoulder surgery and dealing with cancer I bit the bullet.   Theyran it into the bay at 7:30 and it was done at 4:30 so some time involved standing on their head and twisting three ways from Sunday was involved.

Anyway the plugs were toast. I’d actually say I went to the max at 83,000 miles. I’d recommend no one go beyond 75k.

I’ve got pics of the plugs that tell the story but I have no idea how to post them.

I’ve got pics of the plugs that tell the story but I have no idea how to post them.

It would be interesting to see those pictures.

Ron, I could send them to you tomorrow . If could post that would be great

Ron, I’ve emailed you some photos.  I measured the gap at 69 thousands.

Joseph - I believe the OEM’s were platinum, not iridium, correct? Is the part number still visible on the old plugs?

Glad you are doing well and back to driving your PC again. Where did you go for labor? I totally concur about paying someone younger to change those ten plugs rather than contorting and twisting one’s self into a pretzel. I also  dread bad threads and Helicoils. Mine only has 62k miles, but maybe I should just get it done before the rest of the experienced Ford service techs either retire or move out of state.

Cal,

Maybe this will provide some comfort.  My brother has a 1998 Starflyte, built on a 1998 E350-V10 chassis, one of the earliest V10s.  He had his plugs changed without incident about 5 years ago with well over 100,000 miles on the originals.  Maybe he was one of the lucky ones.

Today his rig has around 175,000 miles, the V10 going strong.  He did get his transmission rebuilt about 4 months ago, but the engine has been a real trooper.  Little issues like his EGR piping needed replacing and some typical periferals, but nothing serious with his V10.

My plugs were worn to the point of twice and more of the recommended gap.  Work load etc is going to play a part I’m guessing as well.  My transmission I have hot flushed every 30,000 miles.