I just bought an 04 FX4 with 77K miles, no warranty and have the below problems:

1) Engine knocking from passenger side when engine warms up. Cold idle sounds perfect, no problems.
From the way it sounds on this forum, I need to perform TSB 06-4-7 (previously 05-15-8) and replace the VCT phaser although some posts reflect this fix did not resolve their problem. Success rate=Medium Approx cost=$950

2) Shudder in rear end during slow speed turning.
TSB 06-2-16 replaces fluids, add friction modified, lube axle and replace clutch pack. Success rate=High Approx cost=$150

3) Howl\Whine from rear end
TSB 05-23-3 replaces gears and fluids. Seems that the majority of posts related to this are around a year old and most victims did not get theirs resolved at the time. A few more recent posts indicate the fix was successful but apparently, the mechanic and parts must be perfect. Success rate=Low. Approx Cost=unknown.

I am begging for input since the truck is out of warranty and I will be paying for all the above repairs myself. The dealer won't guarantee #1 and #3 will be fixed so I have a lot to lose if these two don't get fixed the first time.

 

Just FYI, problem one has no negative effect aside from the annoying sound. So you might want to just ignore it.

Problem two is probably fixable with fluid swap and additive. Strange that a truck with 77k would be as tight as a new one?

Problem three is more of an annoyance.

Dealer is not the only place to fix things, just the most expensive.
Chris

 

Well,
I have to say that someone has done their homework. The search tools are what make this site great. Anyway, yes, those are the problems that were, and are, common with the 04's and some 05's. I would say that #1 and #2 are the ones that seem to be fixed with the TSBs were followed. I think that those two would be worth it to have the dealership or someone that would follow the TSB for less money. The third one, which you put accurately as low probability, is up to you since it seems that Ford has not really "fixed" it for most. Out of warranty work is killer, so you may want to consider aftermarket rear gears in the same ratio. Good Luck and welcome to the forum.

 

I just got my truck back and now it runs like brand new. I hope this information can be of help to others who may experience one of these problems:
1) Cam Phaser replaced and no more knock.
Actual Cost ended up being $960

2) Shudder in rear end is gone.
No charge since it was fixed with #3 below

3) Rear end gears replaced and new fluid added. No more howl\whine.
Acutal Cost ended up being $1000.

My Penn Warranty covered number 3 but did not cover number 1 because point of failure could not be proven (this warranty company is very difficult to deal with).

I bought the truck for $18,500 (loaded FX4 Supercrew with leather) and now have a total investment of around 20K so I feel pretty good about it.