May be some who have, and some who have not, seen my previous postings here regarding excessive drivetrain lash, displayed by symptoms somewhat akin to those of a loose differential.
In hopes that it may be of some benefit to someone, I shall post the following:

2002 XLT 4X4, 4.0L, 5-speed manual.

From the beginning, truck would sometimes "clank" when shifting gears or making sudden change in ground speed. Not as bad during upshifts; more noticable during downshifts, etc.
Back to dealer under warranty. First trip; they re-shimmed the rear end to .009 (Ford specs the tolerance from .0007 up to something ridiculously high...). Little improvement.
Second trip to dealer; they replaced the driveshaft with the "latest & greatest" aluminum driveshaft. Said the original had excessive clearances in the slip-yoke. A little more improvement. We're now down to the problem being about half as bad as it was originally.
5000 miles later, the symptoms had once again worsened almost to as bad as they were originally.
Back to the dealer for the third trip; Dealler called Ford Hotline for direction and authorization to effect repair. Ford said "Do Not Repair". Apparently, Ford's tolerances for measured total drivetrain lash is from 3/8 to 1 inch. Mine was .75 inch.
I really like everything else about my little truck, but was beginning to have fleeting thoughts regarding the "Lemon Law" in my state.
After repeated attempts to directly contact the Serice Manager of my local dealership, he finally returned my call. Gave him brief history of problem, and steps taken to date, with polite but firm assertion that the situation was unsatisfactory and that I wished to have a Field Service Engineer from Ford drive the truck. The local Service Manager was unopposed to this request, but did request that I bring the truck by, at my convenience, so that he might drive it before calling Ford Field Service Engineer in on it. Reasonable request, so I took it to him. He drove it, thoroughly inducing the symptoms by repeatedly alternating between acceleration and deceleration in multiple gears. Oh, it showed up big-time! (and on the way home afterward, I found that the symptoms had worsened significantly from his having driven it in the manner in which he did) He agreed that the truck had a problem. Called Ford to request Field Service Engineer to come and test drive it. Ford refused, because they said that this was the first call that they had received on it. They had not logged the previous call because it was a "Do Not Repair" issue. My local Service Manager is acquainted with the Field Engineer, so he called him directly, getting his voice mail, leaving message regarding problem. He agreed to call me when he heard back from Field Engineer. Few days later, I called and left message inquiring whether Field Engineer had contacted him. I received call stating that Field Engineer had requested that the dealership lubricate the slip-yolk and properly torque the bolts on the output flange of the transfer case prior to him coming out to drive. I delivered truck to dealer, for fourth time, for said servicing. In a couple of hours I received a call from the Service Manager, as he was test driving my truck after the services, saying that all seemed well, and requesting that I pick up my truck and drive it and report back to him.
Picked up truck after work, and drove straight home. Although I could still induce some slack in 5th gear, lower gears seemed greatly improved. Then I drove truck to work this morning. Could hardly believe it was MY truck! Not only were shifts "tighter" sounding, the entire truck was "tighter" sounding! Very minute vibrations and noises that I previously had not even noticed were now gone! (sort of like a deafening silence...)
I am pessimistically waiting to see if this improved condition is long-term, but I gotta tell ya, it is really nice at this point.
By the way, I called the Service Manager and expressed my gratitude for his efforts, and those of his mechanic. But I also mentioned that we'd wait and see if it stood the test of time.

Hope this experience may serve someone who reads it. Thank you kindly for your time and understanding.
Thumper47

 

So at the end of day, that slip yoke seems to be a continuing saga of customer complaints. Even the new alum shaft is not being properly assembled it sounds like as the problem came right back. For some reason I had understood the alum version had no slip yoke.

My 2001 has the problem, not too bad, but it seems like you need some crimping tools to do the lube TSB, so I am not sure if I can do it or not. Replacing the driveshaft is about $700 and now you are telling me that it may still need the TSB lube job. Good grief.

 

My '03 has the aluminum driveshaft, and when I took it to the dealer 'cause I was tired of the thump & bump they removed the driveshaft and lubed the slip yoke. So it does not seem that the aluminum shaft is immune to this problem

Bill

 

Has anybody figured out a way to put a grease sert in this dumb thing so it would be easy to squirt it every 10K or so? Thats what Ford should have done as part of their TSB rather than a fairly expensive periodic maintenance action.

The lcoal dealer told me about $200 to lube it with no guarantee it will fix any problem for any duration of time, since to Ford its not "really a problem".

 

has anyone tried using zip ties to hold the boot on instead of crimping? if this is something that needs to be done periodically, it seems zip ties would be easier.

 

I used zip ties on mine and they are working fine. (knock on wood!!!)

 

The boot clamp crimp tools are only a couple of dollars, and available at most parts stores.



If I had to in a pinch, I would use a zip tie, but I prefer the old fashioned metal clamps myself...

 

I am lazy and cheap. If I wacked the metal clamps, and slid the cover a bit, would I have any chance of getting some grease in the sweet spot, without removal of the driveshaft, and put the tie wraps on making it a 10 minute/50cent task. Or does it really have to done like a manicure to have any effect?