Shop told me they won’t change plugs /tune up on my 99 Triton 5.4

[callwill]

Penetrating oil applied a couple of times over a couple of days and allowed to heat cycle will help. once a plug turns loose, tighten it a bit then back it out some more.Keep working it like that. Once you have cleared the carbon build up getting it the rest of the way out should be considerably easier.

 

[Anthony O]

Thanks for the info gentlemen!

 

[Gary Waugh]

I have an 08 5.4l, the plugs get changed every 80k miles, just changed them again, am at 220k miles, still have original coils and no issues, it takes me about 2 hours to change all 8 plugs. I usually disconnect the knock sensor above each spark plug and then disconnect the coil plug, remove the mounting bolt and remove the coil. Then remove the spark plug, usually very tight and stiff. Then replace the plug, refit the coil, reconnect the coil and knock sensor and then repeat the entire process for the next spark plug. I find the passenger side plugs the easiest to get to, for the driver side, I also remove the ducting from the air filter box to the throttle body to make it easier to access the plugs. I put a small smear of copper slip (copper grease) on the threaded section of the new spark plug to try and make it easier to remove later on..

 

[MesaGuy]

1997-2002 2V 5.4L Do NOT have the cracked plug problem. The mechanic was gun-shy because the 2003-2008 3V 5.4L engine DID have a severe cracked plug problem. Just find a yourself another independent mechanic that does a lot of work on Ford Trucks, or do it yourself. If you do it yourself, their is one issue with the 2V 5.4L engine in relation to spark plugs, especially one for vehicles in the condition you described in your original post. e.g. that the plugs have never been previously changed. That is issue is that the thread bore design on the 2V 5.4L was essentially one thread "to little", the engine could have really, really, really used one more thread on the aluminum head (and a slightly thicker bit of aluminum in the head to accommodate that additional thread) than it actually has. So sometimes plugs "blow out" because they are essentially only being head in by two threads of 3, instead of 3of4 or 4of4.

What does that mean for you. Take you time, don't rush or force it. Remove the coil on plug (COP) units to expose the upper plug. Blow out the well of dirt with a air compressor (if you have one), or a can of air (e.g. "Duster" can, Amazon). Then (with the engine cool) spray in some PB-Blaster or drip in some Kano Kroil oil onto the spark plugs into the spark plug wells. (You are taking them out, so some oil doesn't matter). Leave it to sit over night, so that the PB-Blaster or Kroil oil can seep into the threads of the plugs, which haven been in that spot (suck up burnt oil, clocking and locking the threads for 25 years).

THEN, next day socket them out with HAND tools. The whole job is pretty easy except for 3 things. The hold-down bolt on one of the COP (I think its cylinder #6, 3rd one back (from the front) on the drivers side) that bolt is hard to get at because of the fuel rail. (I have bought a 7mm socket&u-joint in one combined piece) from Amazon (I believe Tekton sells them) that makes that job a lot easier. (Worth the $10-20 dollars for the one socket in terms of time and aggravation.) The other two things are the clearance on the rear two plugs (the #4, and #8) is difficult. You usually need to move vacuum and wiring about to get in there, and its hard to get the angle.

But otherwise, the job is pretty straight forward. Doing the overnight sit with PBBlaster/Kroil, will save your aluminum threads when you try to ratchet out the plugs. If you do NOT do that, you have tendency to rip the dirty, crusted up "stuck" plugs in head, and tear the aliminum head threads. So, just lub it overnight, and let it suck up some creeping oil into the threads over night and no problems.

Depending on your budget, this is the time to replace your COP (coils) as well. I REALLY recommend getting the real FORD 5.4L COP Motorcraft coils, even though compared to after-market, they cost a fortune. (RockAuto, or Amazon are cheapest). The after-market coils all work great, for 10K miles, and then, its all over the place. Some keep working to 25K, and others not. In comparison, the Motorcraft coils will reliably give you 100K of service. So assuming you only ever want to do this relatively easy job once, spend the extra money, but it is a big price difference. After-market (Around $50-80 for 8 coils) and Motorcraft (Around $280-320 for 8 coils). So that is an extra approximately $200, but while many an after-market part is good, coils are not one of them. You definitely get what you pay for on this part. The only exception I would make is the Denso 6736000 COP, which is about 1/2 the price of the Motorcraft, but seem to work as well as the original.

On the plugs, get the Motorcraft as well. The engine computer likes them better. Here the price savings from after market to Motorcraft is not all that much.

When putting the new plugs in, definitely use a click-type torque wrench for proper torque. The plugs are just head in by 2-3 threads of aluminum. It needs to be snug, but not over-torqued, because those threads cannot handle over-torquing. And over-torqueing the Steel threaded plug, onto the aluminum threaded head, will easy tear out the aliminum, which is how people strip their threads, and then get "blow outs". Mechanics cutting steps, and not doing by the numbers.
Tekton 7mm socket + universal
Capri 7mm socket + ujoint

Coil COP for 5.4L Triton, 2V 1997-2002 Engine

Motorcraft or Denso plug prices at RockAuto

 

[Yupster Dog]

When putting the new plugs in, definitely use a click-type torque wrench for proper torque. The plugs are just head in by 2-3 threads of aluminum. It needs to be snug, but not over-torqued, because those threads cannot handle over-torquing. And over-torqueing the Steel threaded plug, onto the aluminum threaded head, will easy tear out the aliminum, which is how people strip their threads, and then get "blow outs".

Actually you do want to over tighten some.
Not tightening enough is the main cause of "blowout".

That is why it's usually the back ones to blow out first,
because they are hard to get to and tighten properly.

Scroll up to my previous post (#6) and watch the video, Makuloco explains the proper tightening procedure.

 

[1955moose]

I have a 2000 Expedition, same motor, same deal. Here's the skinny. The spark plugs don't break on removal, their just a P.I.A. especially the rear 2 on driver's and passenger side. The other biggest issue is Ford in all their infident wisdom, decided to put about 4-5 threads too few on the sparkplug holes in heads. If they aren't torqued just right, about 22-24 ft lbs. They spit out like a watermelon seed under pressure. This requires a thread insert to be installed on ones that ejected, not fun. I've got 133k on my originals, with no engine miss. Even the dealer can screw it up, if the tech is in experienced. And none will guarantee it won't happen. Count on anywhere from $300.00 to $500.00 for job. Run a computer scan at parts store or buy your own, their cheap enough. And replace just that coil and wire. First. It's a special 9/16 spark plug socket if you want to tackle spark plug yourself. Anywho that's the whole magilla on this stupid plug thing