In reply to Professor_Brap (Forum Supporter) :
The floors on this truck have already been "repaired" once. The "repair" (basically a piece of thin metal cribbed from who knows where) has since rotted out! That said, it can't be nearly as bad as the Shelby CSX floors I did about 10 years ago. I had to actually make those floors and there wasn't much left to weld them to. At least I have reproduction pans this time, and the rot is contained to only a couple spots. Most challenging part will be the seatbelt anchor area, which I have already replaced on the passenger side in the past.
I was out and about doing Truck Stuff last weekend, and the squeaking at speed was getting so bad that I decided to do a short YouTube video on it. Check it out (volume up)!
I still think it's axle u-joints, but it's possible that it's wheel bearings, even though I already did those a couple years back with quality parts. It sounds like it's coming from the wheel area, and if you give decent throttle, it for lack of a better term gets "chunky", and you can feel it in the wheel. It's not the transmission, since the noise is with wheel speed and independent of what gear it's in. When you give it gas, it gets worse. It's to the point where I probably shouldn't be driving it. How would one diagnose a bad axle U-Joint?
i've never heard a wheel bearing squeak.
u-joints can definitely squeak once or more per rev because of the angles they go through. as they wear and their internal clearances grow, sometimes you'll hear a very metallic "ping", like a hammer striking a pipe, when going from Drive to Reverse.
In reply to AngryCorvair (Forum Supporter) :
There's some driveline clunking when dropping the truck into gear or reverse, which could be the driveshaft u-joints or a sloppy transfer case. This isn't that, though. This is a high-pitched, oscillating squeaking/whirring sound that happens usually at low speeds and especially on accel/decel. When cruising, it's not really there until you increase/decrease speed. It's especially prevalent on acceleration. If you really get on it, it's more of a chunky grinding sound. Engine and trans mounts are new, BTW.
i couldn't really tell from the video. i will say that you are unlikely to hurt your truck by correctly replacing U-joints.
In reply to AngryCorvair (Forum Supporter) :
It's been on my to-do list for a while, but I have a torrid history with replacing u-joints. Last time I replaced some, the driveshaft in my old F-150 completely LEFT the truck. I was on a date at the time with two girls in the truck. I had to pull over, and the only place I could pull over was the parking lot of an adult store. That did not go over too well.
In reply to Tony Sestito :
I did say "correctly" 
Tony Sestito said:
In reply to AngryCorvair (Forum Supporter) :
torrid history... with... shaft... on a date at the time with two girls in the truck... parking lot of an adult store.
Selectively deleting words from your post made it significantly more readable.
After doing some research (and watching some videos), I'm confident that I can replace these U joints the CORRECT way this time. I think what happened 20+ years ago when my dad and I replaced them last time, my dad smacked the driveshaft with a hammer causing it to go out of balance while trying to smack out the joints. I have a vague memory of this when we were installing the new joints. That is obviously very bad.
So with that said, I ordered all 6 U joints and new ball joints. This takes precedence over zapping in the new floor pans, because I can't drive the thing right now the way it is. I also needed to do the ball joints to pass inspection this summer; they are getting bad, and they are going to be right there while I'm doing the axle joints.
This is gonna be fun.
Tony Sestito said:
After doing some research (and watching some videos), I'm confident that I can replace these U joints the CORRECT way this time. I think what happened 20+ years ago when my dad and I replaced them last time, my dad smacked the driveshaft with a hammer causing it to go out of balance while trying to smack out the joints. I have a vague memory of this when we were installing the new joints. That is obviously very bad.
You're stirring up memories here. It's been a decade or three since I replaced U-joints, too, and IIRC it was done on the ground, with a hammer. It was misery. It you have access to a shop press, or even a decent bench vise, it should be a whole lot easier.
I should probably replace the rear UJs in the J20. It makes that loud pinging sound when I drop it into gear.
In reply to DarkMonohue :
I have a good swivel bench vise, and I plan on borrowing my friend's shop press just in case. I will be renting or buying some additional tools to do the job as well. Learned with the front hub/brake situation a few years back to get all the tools up front or you're gonna have a bad time.
Let's play the game Fun With U-Joints!!!
Yesterday, I decided to start in on replacing all of the truck's u-joints, starting by removing the rear driveshaft. Getting the shaft off was simple: after marking the driveshaft and the yoke, you unbolt the retainers and it comes off.
These u-joints appear to be the OEM parts from 44 years ago.
While I've seen worse, the rear one was extremely stiff and binding up, while the front was super loose. It was time to replace them.
I then got it up on my vise, being EXTREMELY CAREFUL on where it's clamped and with as little force as possible, and pressed the old joints out.
)
Another shout-out to my new Ryobi impact gun. On setting 1 (the lowest setting), this thing easily and carefully pressed out the old joint. Or at least I thought...
One of the ancient caps looked damaged on initial inspection, and it crumbled under light pressure when removing it. I had to pull the remnants out in chunks, and it created a few burrs in the yoke, which I carefully filed out.
Again, this thing was smoked.
Now, here's where the real fun begins.
With the bottom caps removed, I placed both the old and new joints next to each other to compare them. The new Moog joints have the same cross sizing, but the cap appears to be slightly different. PLEASE NOTE: the cap is not fully seated here; there are no needle bearings in the cup of the cap, but the grease seals wouldn't allow it to sit all the way down on the cross. I can press it with a finger to make it squish more.
And things got worse once I tried installing the joint in the shaft. No matter what I did, I couldn't get the two caps centered enough to get the retaining clips on. Did I buy the wrong joints?
After cleaning up the old joint, it's in fact an OEM Mopar Detroit 2266909 joint, aka part # 7260. These trucks either came with the 7260 or 7290 joints, which are larger and came on the bigger trucks. The Moog 246 (what I purchased) cross references to the Detroit 7260, so these should be correct. Looking at the two joints, I noticed that the cap design on the Detroit joints is slightly different than the Moog (and all other aftermarket) joints I've seen. The biggest difference is the grease seals; while they are largely missing on the old one, the remaining ones are thin, whereas they are extra large on the new one.
I posted on a FB group for these trucks about this issue, which is always a roll of the dice, but I did get a few knowledgeable people tell me that these are the correct joints and you just have to make sure the grease seals are seated correctly or else they won't seat correctly. I'm going to try again with these later today, as well as measure them with my micrometer to make sure they are in fact close enough to work.
In reply to Tony Sestito :
It's possible you got the right box with the wrong part in it. Check dimensions carefully. I'd hate to see you Humpty Dumpty that thing.
In reply to AngryCorvair (Forum Supporter) :
I measured an old joint and a new one just now. There's a 1mm difference in the cross and overall with the caps on. I can get them in enough to get the clips on, but they will stick out .5mm on either side. Not sure if that is an acceptable tolerance or not. Seems like all of the aftermarket joints are similar.
UPDATE: Joint is in.
From everything I'm reading, as long as the retainer clips are in, that's all that matters. The caps do stick out a little on each side, but I guess that's normal for aftermarket stuff. Guess I'll keep marching forward and replace the rest.
In reply to Tony Sestito :
Wish I had seen this earlier....On inside clip U joints like yours the external protrusion of the caps is random across production. Some do not protrude. So long as the protrusion is approximately equal all will be OK. Do pay attention to balance weights if present, and they're relationship to your yokes, especially if the protrusion is not equal. The seals always need a little compression when they are new and are mostly gone when you dis-assemble.
In reply to TurnerX19 :
Thanks for the heads-up. I'm hyper sensitive to issues related to u-joints based on past experiences (see my post above about launching a driveshaft into the ether).
I finished the transmission side of the rear shaft last night. This side went a little easier, and the sides stick out the same on each end after the clips were seated. I also read to give both yokes a few smacks near the caps to settle the joint so it moves freely. They aren't flopping around in there, but not exactly loose, either. Hoping that once I grease them and put a few miles on them, they free up a little more. I really don't want to launch a shaft into orbit again.
It's been a couple weeks, mainly because I was on vacation out-of-state, but I was able to get the rear driveshaft back in and went for a test drive after greasing everything as needed. No weird noises or vibrations from the back shaft, and the rear of the truck was less clunky, so I'm calling it a win. The bad news is that the squeaking and clunking from up front still needs to be addressed. And the extra fun part: I am moving this weekend to an apartment for the next year as we start renovations on our house, and the lease says that we can't wrench on things in the parking lot. My "work area" (aka my driveway) will be fully occupied by a dumpster and construction equipment, so working on the truck at home is not happening. I'm hoping to schedule some time at my friend's home shop to finish the job in the coming months. I'll get it done, one way or another.
Also, the good news here is that the truck can actually come to the apartment. This will be good since we're going to need it to do some light moving and I can keep it away from construction hazards and the car-killing pine trees in my backyard. The only caveat to this is I need to come up with an effective way to disable the truck so potential thieves will not be able to get it going. As you may know, starting an old Mopar is as easy as popping the hood and jumping the fender mounted starter relay terminal with a screwdriver. I may unplug the EFI ignition box, pulling the coil wire, or even yank the battery when it's not being used. It's a relatively quiet place, but I want to make absolutely sure no one messes with it.
Jumping the starter relay on the fender will only make the starter crank over, not start the truck. It's no different than jumping the relay on the starter of a GM. You won't have voltage to the ignition, nor will you unlock the steering column, for that matter.
That is an Old Wive's Tale spread on YouTube by VGG...
In reply to Russian Warship, Go Berkeley Yourself :
That is a good point. Also, my ignition system is no longer stock, but it is still powered (and triggered) by the "key on" position on the column. Even pulling the fuel pump relay would probably be enough to thwart theft. It's hidden, and the average criminal wouldn't even think about it. There are lots of ways to disable this thing.
Recently, I've had to put the ol' Power Wagon to work, even though it's ailing.
We are doing an extensive house remodel project, and I've had to do many runs to home improvement stores, moving things back and forth to our temporary housing, and more. The truck is handling it like a champ, and I've been knocking down 10mpg with all the back-and-forth, which is terrible-yet-good, if that makes sense. Whatever's been squeaking is still doing it, but it hasn't gotten worse, so that's good. I will hopefully be able to address some of the issues before state inspection in July. I'm still convinced that it's the wheel u-joints, but it's also possible that part of the noise is the body rubbing against each other. I was leaning on the fender the other day and heard a squeak, and rocking the truck back and forth replicated it. Hmm....
Also, the run between my house and the temporary place is a lot of fun, and there's this one country road that the truck LOVES. It can really let loose back there, if you know what I mean. It made me pull over and take some pics.
Still love this stupid truck, warts and all.
Hose down the axle u-joints with PB Blaster and see if the noise gets quieter for a bit.
In reply to Russian Warship, Go Berkeley Yourself :
Pretty sure that was one of the first things I tried back when I heard the noise. Didn't really have an effect, but it couldn't hurt to try it again. It needs to be fixed right at this point, as I'm almost positive these are original to the truck.
