Basically the most current version for the trucks are the "B" wires and the "C" are for the motorhomes
7.3L spark plug/coil wire failure
- OP 🔹 Stonegrey20
- Start date
Yes, you could look at it that way. I think some of the confusion with the current wires coming from the factory is this; they are labeled on the factory plastic packaging if you bought them separately as “b” wires. These are the 3rd version of the wires developed for our trucks so in theory they are really the “c” version. A=1st version, B=2nd, so on and so on…
You are correct that the “c” packaged wires are specific to the motorhome chassis.
I believe @Modman covered a few pages back how ford actually labels the wires in their own way to designate the version. This is specific to the last 2 letters found on the plug wire itself. Even though our wires say “mb”, they are NOT the “b” or 2nd version.
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I'm little confused. Are there 2 different "c" types now? Replaced mine with c about 6 months about. Pretty sure they were the matte finish ones with spring and greater angle...might have to have a look under hood???
Yes those are the true "C" version, designated for the RV chassis, but completely compatible with your truck. As mentioned earlier, there are three renditions now for the RV designated wires, and only two renditions for the pickup designated wires. I recently bought the RV Chassis "C" version (with the aluminum shield and boot spring) for my truck last week and they fit and work fine. My truck was built in March of 2021 and it came with the second rendition truck plug wires from the factory. They will probably last a long time but I have the new wires as a backup/next gen set for down the road.
So I had this issue again over the weekend. We were towing up a pass and just at the top got the CEL. There was construction so while we waited for the pilot car I ran forscan and found it was the misfire on cylinder 2. This same cylinder had the misfire issue in August of 21. I had a spare in the truck so we limped to our camp spot and swapped the wire when the engine cooled. Cleared the codes and we were good to go.
I called Ford this morning an found that the plug wire used in August was part# LC3z-12286-B that's the same version I had as a spare. They are going to order the C version but I'm not confident that it will fix it permantly. Any other ideas?
I called Ford this morning an found that the plug wire used in August was part# LC3z-12286-B that's the same version I had as a spare. They are going to order the C version but I'm not confident that it will fix it permantly. Any other ideas?
What are the last 2 letters found on your plug wire?
I think heat radiating from the exhaust manifolds into the plugs is another issue. Might not be worth it to wrap OEM manifolds, but with wrapped aftermarket headers I bet the troubles would be gone.
Both are MB
Interesting. I think this is the first time I have heard of a wire issue with the 3rd generation mb wires. When the dealership is suggesting changing these to the c wires they must be referring to the ones that @RedZilla just purchased. With your current wires being the mb’s, you have the latest generation currently installed in your truck that were designed for the super duty chassis.
I’d be curious if the dealership could verify if they are suggesting to go with the rv chassis “c” wires to fix the problem.
What was the ambient temperature when this happened and how much weight were you pulling? Just curious.
I’d be curious if the dealership could verify if they are suggesting to go with the rv chassis “c” wires to fix the problem.
What was the ambient temperature when this happened and how much weight were you pulling? Just curious.
According to Ford. Just think how many shitty B replacements that got produced. Have to get rid(sell) them to someone.
I'm quite sure there's no specific reason why the design of the C wire would only be made and specified motorhomes.
Read post above. Ford won't direct dealers to do that UNTIL they've spent up their supply of B's.
I was the one that suggested the C wires to the dealership as I thought they were fixing the issue. They were okay with ordering a single but won't do a full swap. I think I'm going to buy a full set of C wires and swap them all to be safe and just carry around a set of spares. Seems ridiculous to have to do it but I'm not super confident with it when towing.
The ambient temp when it failed was mid 90's but as we pulled up the mountain the temps dropped into the low 80's. We had only been towing for two hours. However we did let the truck idle for about 30minutes while we had lunch since we needed to keep the dog cool.
The ambient temp when it failed was mid 90's but as we pulled up the mountain the temps dropped into the low 80's. We had only been towing for two hours. However we did let the truck idle for about 30minutes while we had lunch since we needed to keep the dog cool.
How much weight were you pulling? I placed and order from rock auto a week ago and they are scheduled to ship out tomorrow. Just so you know... there might be a little wait for them.
Around 12,000
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Is it possible that there is an updated Coil. It has yet to be swapped? Same cylinder twice makes me think they should at least eliminate that.
Got the WR-6167’s today from rock auto. I’m no engineer, but these seem more heavy duty and better insulated vs the stock 6164’s.
The metal shielding around the spark plug is much wider, however it’s shorter as it wraps up where the wire becomes exposed compared to stock. I’m going to chalk this up to the different angle of the shield on the 6167’s. These flare out and away from the headers quicker than the factory ones. If it wasn’t for the metal tabs on the stock wires… the stock ones would fit inside the 6167’s.
In addition to the metal spring, the orange/red sleeve that fits around the spark plug inside the metal sleeve is also thicker material.
Swapped all 8 out and will run these for a while to test them out. I know this swap isn’t necessary, but if there is a better quality or superior design out there I’m all in. IMO, these are both.
FYI.. the drivers side is a cake walk. The passenger side is a pain in the ass due to access. Had to lay on top of the engine to get my hand in there for the rear passenger wires.
The metal shielding around the spark plug is much wider, however it’s shorter as it wraps up where the wire becomes exposed compared to stock. I’m going to chalk this up to the different angle of the shield on the 6167’s. These flare out and away from the headers quicker than the factory ones. If it wasn’t for the metal tabs on the stock wires… the stock ones would fit inside the 6167’s.
In addition to the metal spring, the orange/red sleeve that fits around the spark plug inside the metal sleeve is also thicker material.
Swapped all 8 out and will run these for a while to test them out. I know this swap isn’t necessary, but if there is a better quality or superior design out there I’m all in. IMO, these are both.
FYI.. the drivers side is a cake walk. The passenger side is a pain in the ass due to access. Had to lay on top of the engine to get my hand in there for the rear passenger wires.
- Jan 20, 2020
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- 2020 F250 7.3 Tremor Lariat, Magnetic w/chrooome
- Santa Cruz Vala
I have had the "C" RV wires on my 7.3 for 8 or 9 months with no issues. The spring makes it easier to install, so that's a bonus. Just got done towing our TT around the Olympic peninsula last week during the heat wave; no issues there, even when pinning it at 4500 rpm for a couple long climbs at highway speeds.
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8, yes
