Ford V10's Blow plugs?

[Bob Witt]

I have had 2 V10's but today someone told me they are a problem for blowing sprk plugs because of the lack of threading in the head, any truth to this?

[SuperDad]

Yes, only in the 1999-2000 models. I had one in a 2000 Ford Excursion

[BFlinn181]

The plug problem was only in the first couple of years and Ford developed a kit to repair the plug socket in the head when it happened.

[scotts_rv]

This was a common problem on the early Ford modular engines, 4.6, 5.4 and 6.8. I thought the problem was out to about 2003 though. Just Google "Ford spark plug blowout" and you will get a bunch of threads on it. It has created a cottage industry fixing these problems.

-Scott

[jamesrxx951]

Im not sure if I would consider it a huge problem. However I can and has happened. Seems to happen on the 5.4L based on what I have seen personally but it can happen on the 4.6 and 6.8 also. I have a 99 V10 and I changed my plugs over to the newer updated plugs with more threads. Used high temp anti seize and torqued the plugs with a torque wrench. I used a scope on my heads to count all the threads in each hole. I had 5-6 in each bore. Not great but not bad either.

Remember, overtorqueing the plugs can cause the threads to distort. This can be a greater risk than under torqueing. The threads hold the plug in while the light torque on the plugs keep the plug from rotating out. Not much torque is needed to keep the plug from backing out.

[wa8yxm]

Any truth to it: YES. as with many things like this there is some. Ford was fairly quick to fix the problem by a very slight re-design.. So odds are you do not have one of the affected engines.

[Stan.Birch]

Yes there was a problem with early Ford 4.6, 5.4 and 6.8 engines launching plugs, but with a stable full of such entities we have never had a problem.

With our 1999 V-10, I changed the plugs at 50,000 miles, and installed the updated plugs designed to fix the problem. The new plugs were installed with little more than a trace of anti-seize; and due to the anti-seize, torqued the new plugs to a compromise:15 ft/lbs.

8 years and 35,000 miles later the plugs are doing fine in our 1999 motorhome V-10, as well as our 2000 Merc.

At 85,000 miles, our V-10 purrrs along just like new, with no ticks or clicks, and oil useage running around a quart per 4000 miles.

[Arch Hoagland]

Bob Witt.....What model and year vehicles do you have?

[Bob Witt]

It is an '06 Itasca 30 ft class A

[Adaycj]

I've fixed dozens of these. Well, 52 according to the remaining stock of TimeSert kits. The problem exists from the 97 through 2004 model years, and can be in any of the V8 or V10 engines. I have given away a few of the inserts.

The repair kits are a little scary, but I've never had one not work out. The whole Triton line, and its close cousins are good reliable long lasting engines. I wouldn't let the plug fiasco steer you away from a vehicle with one of those engines. Personally, I'd be more afraid of exhaust manifold leaks. It' more money and hassle to fix, and seems to be more common at this point in the life of engines that old.

When working in the Romeo plant, trying to help with piston slap issues, I was told that the design with less than 5 plug threads was engineering that was handled by the same group that worked on the exhaust studs. I don't have any proof, but its a cool old rumor. Maybe there really is just one guy that needs a good swift kick.