Bad vibrations (Part 2!)

[5.7 hemi]

Pull it apart, post pics of everything and we can go from there.

 

[Dave145]

I guess thats pretty much the next step. Sucks because I need this car Saturday for a cruise night just out of town. Kinda looks like I can either miss it or drive out there vibrating all the way. My suspicions are that the axle itself is somehow vent and the bearings are chewed up due to neglect.

 

[5.7 hemi]

Anything is possible, but until it’s apart, it’s a guessing game.

 

[Dave145]

I agree. I will see what I can do over the weekend

 

[Ski 61701]

Is the rear an original 64 or has it been changed out to a 65 ?
If its a 64 they are a royal pain to set the clearances on the outer bearings, shims are usually needed. Not sure where you'd even find them nowadays.
Highly suggest getting a fsm for the tapered axle setup.

 

[Fran Blacker]

Is the rear an original 64 or has it been changed out to a 65 ?
If its a 64 they are a royal pain to set the clearances on the outer bearings, shims are usually needed. Not sure where you'd even find them nowadays.
Highly suggest getting a fsm for the tapered axle setup.

Agree ..... ski

 

[threewood]

Is the rear an original 64 or has it been changed out to a 65 ?
If its a 64 they are a royal pain to set the clearances on the outer bearings, shims are usually needed. Not sure where you'd even find them nowadays.
Highly suggest getting a fsm for the tapered axle setup.

Not as easy as the later model adjuster but pretty simple nonetheless. I have several spare shims and have made a few with thin spring steel sheets with a cut so they can be put on without disassembly. I believe the op already installed new bearings.

 

[Fran Blacker]

Google mymopar.com click on tools/reference and scroll down past dodge and Plymouth. Download a 1964 Chrysler service manual has the same rear. Page 71 start of axle adjustment procedure, I'd make sure that was right before tearing into center section.
http://mymopar.com/index.php

 

[Dave145]

Well we are back in the hunt. I brought the car over to a friend of mine tonight for him to look at it and feel it out. After driving and playing with the car, he says the rear axle definitely isnt the problem. He says if it was truly bad that the bearings would howl while driving. He also recommends not running cars unloaded on jackstands.

We spent a good couple hours starting at this thing on his lift. Even he is pretty stumped. To him it feels like a tire shake, though neither of us know why.

He also measured my pinion angle again, but this time with a true pinion angle gauge. Final readout at the rear axle is .5° at the very most. He is suggesting getting some 2° shims, as my 4° ones are likely too much. However, he does NOT believe my killer vibration is coming from this.

So we are back on the hunt for this elusive vibration.

 

[5.7 hemi]

Check motor mounts (k-frame) for cracked welds?

 

[the mississippi madman]

I would still take the axle apart and check everything out

 

[Dave145]

The k frame and all it's associated welds look solid. Weade sure to check that last night.

We don't really see much of a reason to pull apart the axle after last night. We put it up in the hoist and spun each wheel to feel them turn and listen to it. Nothing really makes any noise and nothing feels wrong back there. The loud noise I had heard was just because the rear end was free spinning. We don't hear it or anything else goofy from the road. At some point it'll come apart, just not right now.

 

[70sixpkrt]

I would pull the axles anyway and just check things out. I decided to pull mine just to check them and found this.

 

[Dave145]

Fortunately I have already replaced both my outer wheel bearings in the rear axle awhile back. The axle isn't coming apart any time soon. If it ain't broken don't fix it. Exploratory surgery even in his case would likely just be a waste of money because this thing isn't bad.

 

[5.7 hemi]

Are your leaf spring hangers tight!

 

[Dave145]

Yeah they are definitely tight haha

 

[5.7 hemi]

Just asking, but have you gone over all the nuts/bolts that hold everything together to make sure nothing is loose?

 

[Dave145]

Yes I have. Front to back I've checked all the K member bolts, motor mount bolts, trans mount and crossmember bolts, trans flange and u joint bolts, and of course the rear axle bolts and leaf spring hardware. Lugnuts have been double checked and torqued too (which sucks to do, because the PO has both 3/4 and 13/16 nuts on it). All steering components are tight and have cotter pins installed to hold the castle nuts in place. All backing plat bolts were tight when we redid the brakes a year ago but I didn't check those at this time...

I think I will likely have the tires balanced again to get the balancing beads out of them and use conventional weights this time. I will also have the alignment corrected and brought to spec. I will post up a chart of measurements I found for the car, feel free to tell me your thoughts/opinions on the various setups.

I will at some point try some 2° shims like my friend suggested just to try something else I suppose once I have some time and $25 to throw at that. While he says my angle is incorrect, that's not the cause of this vibration.

 

[Brewzer67]

Is there any reason you are avoiding opening up the rear end and looking at the gears, checking the backlash, etc.? It seems you are spending a lot of time looking at everything else except the rear end itself. A number of the symptoms you describe can all be attributed to an improper crush sleeve setting and/or gear issue/setup. Since you've had the car for a while and the problem seems to be getting worse, worn gears wouldn't be out of the question.

 

[miller]

Had my assistant push it up to 75mph. Now the trouble starts. The driver's rear wheel continued to spin true. The driveshaft and driveline spun perfectly. But the shake started. The passenger wheel, which had been dormant this whole time, began to shake violently, as did the body of the car. During this time, the helicopter sound was again present. Had my assistant let off the gas, only to hear a loud whirring noise come from the rear end.

Put two and two together. If it smells fishy, probably is fishy.
From what you've described, at least part of your problem is there...wheel, or axle, or both.