Diagnosing bad axle pivot bushings?

[Darrman]

I am still on my quest to figure out the popping noise on my X. I got under it the other day and was inspecting the pivot bushings.
The drivers side beam appeared to be ok, but the passenger side appears to be sitting crooked, ie the beam itself is slightly crooked to the holding bracket. I looked close with a flashlight and the bushing appears to be wallowed a bit, but I dont really know. I dont know how a truck with 93k could already be shot, but then again this is the first 4x4 I have had in awhile.
Can anybody with some experiance at these bushings tell me? Thanks!

 

[Rhett]

You might be chasing your tail, so to speak. You may never 'fix' the pop noise you hear. The TTB front end is noisy by definition. Most of the time the radius arms will give a pop every now and then. I've never owned a 100%-under-all-flex-conditions quiet one.

The axle pivot bushings last a long long time, as in 150,000 miles+ minimum.

Have you taken the truck to have it aligned, and did the alignment guy tell you the axle pivot bushings were making it hard to align? I have never heard them say that, usually its saggy springs and so forth.

 

[Darrman]

I am positive its not the rad bushings, this thing now pops all the time, anytime you hit the brakes hard or reverse directions, or turn the wheel hard. The axle pivot makes the most sense as the cause, other than the ball joints which are fine. But to check I have torqued the rad bushings to correct spec, and have tightened the rad bracket bolts, no effect at all.
I am debating sending it in to the dealer to check, I have run out of ideas and patiance with this damn ttb.
I have the new poly axle pivot bushings, I am thinking of installing em, I dont think I will be able to do it myself tho.

 

[Rhett]

I am positive its not the rad bushings, this thing now pops all the time, anytime you hit the brakes hard or reverse directions, or turn the wheel hard. The axle pivot makes the most sense as the cause, other than the ball joints which are fine. But to check I have torqued the rad bushings to correct spec, and have tightened the rad bracket bolts, no effect at all.
I am debating sending it in to the dealer to check, I have run out of ideas and patiance with this damn ttb.
I have the new poly axle pivot bushings, I am thinking of installing em, I dont think I will be able to do it myself tho.

I prefer OEM axle pivot bushings. You may not like the ride you get with poly axle pivot...

Forward and reverse pops are most likely going to be radius arm bushings. The axle pivot...well...I have not known the a.p. to pop on forward and reverse. usually up and down flex and uneven weight between the two sides of the front end will elicit a creak or groan from the axle pivot.

If you have more than 150,000 on the truck then it won't hurt to change the axle pivot out, it's just usually not necessary. I'd wager it won't solve your pops either, and you'll get a ride you won't like with that new aftermarket a.p.

The slip yoke on the driveshaft will also pop in forward and reverse driving, if it needs lubing...keep that in mind. That's an easy 5 minute job.

Also the springs, the spring seats, can pop. The axle pivot just usually doesn't pop when going forward and backward. That's almost ALWAYS out of the radius arms or the springs.

If you want the TTB to be quiet, you won't ever achieve that goal. My best advice is to get some rubber (OEM Motorcraft from Ford) radius arm bushings, install them, and that will be as quiet as you can get it...and go from there. Even with new bushings, you can get pops.

 

[Creager]

^^ yep, everything he said

 

[410Fortune]

the axle pivot bushings are a metal stamped piece with a rubber insert, the metal bushing is pressed into the beam and then flared to keep it snug (big ass press I am guessing)
This is why you haev to use an air chissel to get them out and replace them
It is possible the beam has come loose on the metal bushing, allpwing the beam to slide up and down the bushing hitting the pivot bracket front or rear.
When I replace axle pivot bushings I use the stock style and I tack weld the bushing to the beam because I do not have the means to flare the metal bushing like Ford did

Other things that will clunk:
Coil comes loose
radius arm to beam bolts come loose (not good)
Loose shocks
Bad/loose tie rod end
Loose pitman arm
Axleshaft slip yoke on pass beam, etc.

Best thing to do is support the truck both front tires off the ground and do a shake down test, inspec the calipers, rotors, wheel bearings, hubs, slide pins, tie rods, pinch bolt on the camber bushing, etc...

A visual inspection of the radius arms will not always turn up an issue, the heat guards and nylon rings can hide damaged bushings, also they can be loose at the nut.

the ttb typically is noisy, but not as you describe....

 

[Darrman]

Thanks guys, I appreciate your help. One way or another I am going to kill this noise. If it wasnt so often I would not worry about so much, but it is driving me nuts, and its embarrassing when I have put all this work and money and the damn thing sounds like a P.O.S. just backing up, lol.
Anyways, I have done the following:
Checked pads, rotors, replaced both, checked calipers, like new condition.
Repacked hubs and bearings, replaced drivers side spindle bearing and all seals on that side, checked ujoint, good shape.
Replaced rad bushings, front sway bushings, and greased em good with the supplied grease.
new lift coils, new skyjacker shocks, coil insulators are in good shape and lined up right, coils are fully seated.
What I have not done:
Replace the tie rod ends, drivers side is shot, passenger is ok, but might as well do both. Inner joints are ok.
Jacked up the truck and let the beams sag, I picked it up by the beams to check steering, quiet as a mouse then.
The main thing, this pop has persisted BEFORE and AFTER I have done all this stuff, so the common things I have tried have done nothing. What it has done is gotten worse the last couple months, used to be random, now its all. the time, and its loud as hell.

 

[Rhett]

You didn't say anything about the slip yoke. It's a simple lube job, and stranger things have happened...

 

[Darrman]

I will give it a try tomorrow, hopefully thats it.

 

[LXNavajo_94]

actually mine was poping like you say when you hit the brakes and such I found that my radius arm bushings were just about totally gone this might be your problem then it might not

 

[Darrman]

Ok, I am pretty sure what is making the popping noise, finally, but have no clue why.
Today I replaced both tie rod ends, which did nothing to the noise of course, but I had my dad turn the wheels again while I watched. The popping was not coming from the front side of the axle, so I watched behind, and what do you know, the whole drivers differential beam and driveshaft are popping up and down with each turn of the wheel. When the wheel is turned one direction to a certain degree, the entire differential will pop upwards, then will pop downwards when its turned the other way. You can see the flex real good where the driveshaft goes into the diff.
Now that its finally out of the bag, does anybody know what is going on? Thanks for any help!

 

[Darrman]

Nevermind, I finally fixed the problem. I feel pretty stupid, it was a loose bolt, the lower radius arm-to-drivers beam bolt. It had already been suggested by someone that this might be the problem, and I had checked it by hand, tight as hell, but what I did not know till this morning is that tight as hell is not good enough, this thing has to be around 200 pound feet, which involves a 4 foot cheater pipe.
Anyways, thanks to everybody that offered up tips, I appreciate it a lot. And to everyone with a popping in the front end, check that bolt. I am happy I no longer have to listen to the pop, with all the new parts, the whole truck is solid and silent.