Having had the transmission main valve body replaced, and IWE actuators replaced, I am probably paranoid about drivetrain issues. (Prior to the valve body replacement my tranny was attempting to downshift to FIRST gear when I punched it on the interstate!) Recent threads about problems with rear differentials and front differentials prompted me to get my 2018 into the dealer (no appointment) to investigate a shudder that I have been noticing more and more.
MY symptoms: a shudder when applying LIGHT accelerator pedal—400 horses will mask this if you just mash the accelerator like a Neanderthal. This occurred in any gear, at any speed, and was more prevalent when going up grades (long hills, or driving into the mountains).
The kicker is, it wasn’t always there (of course), and seemed slightly more noticeable in 4A vs 2WD. Definitely more noticeable in 4A/Sport mode.
After recently towing, it was obvious the problem was becoming worse, and towing a load made it so obvious even the “tech” at the dealership couldn’t deny it.
So I hooked up a 14 foot enclosed cargo trailer and headed to the dealership to see David—the transmission guru. He was familiar with my Expy already, having diagnosed and repaired the valve body issue and IWE’s.
With me just driving up (no appointment), David came out to greet me,..listened to my concerns—and laughed when I told him I had a trailer hooked up ready to go in the parking lot.
Amazingly, he just chuckled and said let’s go take her for a spin. (Small town dealership)
Down the interstate, and back up through local roads, David put her through the paces (immediately aware of the shudder), thoughtfully listening to all the sounds with the windows down. Then he looks at me and says “I think I know what your problem is, but I can’t tell you because you probably will think I’m crazy, so we’ll just go back and I’ll see if I can prove it to you.
As we approached the dealership, he starts to talk about how, years back, he used to get all kinds of trucks in with “transmission problem” symptoms with the old 5.4 Tritons, and nearly all of them turned out to not be a mechanical drivetrain issue at all….
…as soon as he said that my jaw dropped, and I knew. He paused, and I blurted out an expletive or two followed by the words “@#$ing coil-on-plug!”
Yep. He got a good belly laugh out of hearing about my exploits with phantom misfires in my old F150, and eventually of course, me finding out about the well-documented issue with the coil-on-plugs (COP) in the 5.4 Tritons. I replaced four over the lifetime of my F150. So you’d think I would recognize a misfire, right?
Sure enough, he brought his laptop out and hunted around in MODE6 for pending codes and found cylinder #1 misfire. Fords are notorious for not locking in a CEL for misfires unless it gets so bad it’s a complete failure to fire. I felt pretty foolish, but also relieved I didn’t have a more difficult problem.
So, at his recommendation, I started with just the plugs. I bought 6 Motorcraft plugs from the Parts counter went home, and replaced them the next morning. I carefully inspected the COPs, the boots, and the old plugs as I removed them. None of the plugs looked bad, but #1 plug gapped at .033”, while the others all gapped .029-.030. The electrical connector at the top of the COP showed some light carbon buildup in only the #1 location also.
i cleaned everything up, and reassembled, while swapping the #1 and #2 COPs. Figuring if I continue to experience symptoms, I can scan to see if the misfire moved to #2 cylinder — and I’ll know it is a bad coil.
That’s been 2 days ago, and it runs as smooth as butter—no stumble, no shudder. I’m keeping my fingers crossed but it appears David was spot on.
MY symptoms: a shudder when applying LIGHT accelerator pedal—400 horses will mask this if you just mash the accelerator like a Neanderthal. This occurred in any gear, at any speed, and was more prevalent when going up grades (long hills, or driving into the mountains).
The kicker is, it wasn’t always there (of course), and seemed slightly more noticeable in 4A vs 2WD. Definitely more noticeable in 4A/Sport mode.
After recently towing, it was obvious the problem was becoming worse, and towing a load made it so obvious even the “tech” at the dealership couldn’t deny it.
So I hooked up a 14 foot enclosed cargo trailer and headed to the dealership to see David—the transmission guru. He was familiar with my Expy already, having diagnosed and repaired the valve body issue and IWE’s.
With me just driving up (no appointment), David came out to greet me,..listened to my concerns—and laughed when I told him I had a trailer hooked up ready to go in the parking lot.
Amazingly, he just chuckled and said let’s go take her for a spin. (Small town dealership)
Down the interstate, and back up through local roads, David put her through the paces (immediately aware of the shudder), thoughtfully listening to all the sounds with the windows down. Then he looks at me and says “I think I know what your problem is, but I can’t tell you because you probably will think I’m crazy, so we’ll just go back and I’ll see if I can prove it to you.
As we approached the dealership, he starts to talk about how, years back, he used to get all kinds of trucks in with “transmission problem” symptoms with the old 5.4 Tritons, and nearly all of them turned out to not be a mechanical drivetrain issue at all….
…as soon as he said that my jaw dropped, and I knew. He paused, and I blurted out an expletive or two followed by the words “@#$ing coil-on-plug!”
Yep. He got a good belly laugh out of hearing about my exploits with phantom misfires in my old F150, and eventually of course, me finding out about the well-documented issue with the coil-on-plugs (COP) in the 5.4 Tritons. I replaced four over the lifetime of my F150. So you’d think I would recognize a misfire, right?
Sure enough, he brought his laptop out and hunted around in MODE6 for pending codes and found cylinder #1 misfire. Fords are notorious for not locking in a CEL for misfires unless it gets so bad it’s a complete failure to fire. I felt pretty foolish, but also relieved I didn’t have a more difficult problem.
So, at his recommendation, I started with just the plugs. I bought 6 Motorcraft plugs from the Parts counter went home, and replaced them the next morning. I carefully inspected the COPs, the boots, and the old plugs as I removed them. None of the plugs looked bad, but #1 plug gapped at .033”, while the others all gapped .029-.030. The electrical connector at the top of the COP showed some light carbon buildup in only the #1 location also.
i cleaned everything up, and reassembled, while swapping the #1 and #2 COPs. Figuring if I continue to experience symptoms, I can scan to see if the misfire moved to #2 cylinder — and I’ll know it is a bad coil.
That’s been 2 days ago, and it runs as smooth as butter—no stumble, no shudder. I’m keeping my fingers crossed but it appears David was spot on.
