Considering getting one of these 04-08 trucks but it seems the Triton engines all have major issues. The 5.4L 3v has cam phaser issues and spark plugs that break off in the head. The 4.6L 2v has spark plugs that shoot out of the head. If you were to buy a used truck from this generation, which would you pick and how would you prevent these issues? Or maybe you would NOT buy one, knowing what you know now.

It seems like the fix on the 4.6L is to torque the plugs to 28ft-lb. Anyone know where this number came from? TSB? My concern with buying a used 4.6L is that I can't verify if the previous owner had a spark plug blowout and fixed it improperly (anything but a time-sert). Did Ford ever add more threads to the head in the F150? I've read that they changed from 4 to 8 threads at some point, but that was in a Mustang forum.

I could look for a 5.4L where the spark plugs have already been replaced with the one-piece design, but I'm not sure how to prevent the cam phaser issue. I could replace the phasers but is there a new design that does not have this issue? Sounds like the timing chain tensioner can also contribute to this issue, but is there a redesigned tensioner that resolves that issue too?

 

A 2008 5.4 would be a good choice if you can find one. The plugs do not stick in the head on that model year and from what I understand the phaser issue is not a big concern in that model year.

 

Figure the last year run of any vehicle is the least problematic.
That being said doesnt make up for lack of maintenance.

 

phasers and plugs on the 5.4 should be fixed by 2008........... who said the 4.6 had plug problems ?

 

As a long time Ford dealer tech who been into more than his share of the engines mentioned in this thread, I can tell you the phaser issue with the 5.4L isn't generally that common, if the oil changes are done religiously, using only the OEM FL-820S Ford/Motorcraft oil filter along with the proper 5W20 weight oil. The ones I've replaced all the timing drive components have usually been on ones with either exceptionally high mileage and/or extreme neglect (sludge caked when opened up).

As far as the 4.6L engine ejecting spark plugs is concerned, that is only on earlier model years where this was a problem, like the early 2000s. Between 2004 to 2008 though, it was a non-issue.

And yes, on late 2008 and later versions of the 5.4L 3v engines Ford went to a conventional threaded type spark plug design, which can be resolved by simply installing on a set of late 2008 and later version cylinder heads if so desired.

 

I would get the 4.6L 2V but I bought a base model with the 4.2L 5-spd manual new in Jan. '07, which I would imagine is actually the most trouble-free engine in the '04-'08 trucks. Also in vans and some cars. I have low miles on mine (23500) but it is 10 years old. Its starting to get into old age now as far as certain fluids and rubber parts so I really have to increase the time I spend on it.

 

All the 2v engines had plug popping issues according to what I've read from various sources, including this one - Ford F-150 Problems | CarComplaints.com



Buying a used truck, I can't be certain of maintenance unless the previous owner has all the service records. Then they will probably want a premium price


Looks like the 4.6 2v head was redesigned with 8 spark plug threads instead of the 4 in previous years, which helped reduce the chance of them blowing out, but didn't completely resolve it according to carcomplaints.



I think I'll go the 4.6L route just because the cam phaser issue on the 5.4 can be expensive if it does happen. I haven't found much info on the 4.2, I guess there just aren't many out there. I need a supercab at minimum and the V6 seems to be rare in those.