death wobble

[TDHofstetter]

My 68 does this from time to time, always around 35 or 40 mph. I have noticed a lot of play in my front shackles, you think that could be it? It hadn't done it a while, and then I had a slight load in the back, and bam! 4 Times on that 30 mile trip.

ANYTHING loose in the suspension can lead to DW.

 

[Crjcw]

ANYTHING loose in the suspension can lead to DW.

Good to know, I'll just have to go through the whole thing. Its got a closed knuckle Dana 27 up front, and I don't know the first thing about the ball joints on that thing. I tried repacking the wheel bearings because they were loose, but now they seem loose again, I'm thinking about replacing the bearings now. Thx!

 

[LongHorn]

Good to know, I'll just have to go through the whole thing. Its got a closed knuckle Dana 27 up front, and I don't know the first thing about the ball joints on that thing. I tried repacking the wheel bearings because they were loose, but now they seem loose again, I'm thinking about replacing the bearings now. Thx!

Your closed knuckle axle does not have ball joints, but it does have upper & lower bearings.

 

[Crjcw]

Ok, that makes sense. There doesn't seem to be any movement in those joints, it more seems to be in the wheel bearings. Is this an ok axle? Everyone seems to think its junk. I would of course like to have a disk brake front, but other than that, I just don't know.

 

[LongHorn]

Ok, that makes sense. There doesn't seem to be any movement in those joints, it more seems to be in the wheel bearings. Is this an ok axle? Everyone seems to think its junk. I would of course like to have a disk brake front, but other than that, I just don't know.

It's the old style closed knuckle, but it's no weaker than the late model Dana 30 in the ring & pinion & axle area.
Especially the Wrangler with the long side axle disconnecter.
Ball joints make alignment adjustments easier.
Most people like the newer style axle joints better.
That style has a wider turn radius, less parts availability & of coarse drum brakes.

 

[TDHofstetter]

If the wheel bearings feel loose now... that's not necessarily a good reason to change 'em out. Wheel bearings need changing when they're DAMAGED. Loose doesn't sound like "damage".

When you did it last time, did you preload the bearings before you adjusted 'em & locked the nut? If you don't preload 'em, you won't get a good adjustment & they'll seem loose afterwards.

 

[Crjcw]

If the wheel bearings feel loose now... that's not necessarily a good reason to change 'em out. Wheel bearings need changing when they're DAMAGED. Loose doesn't sound like "damage".

When you did it last time, did you preload the bearings before you adjusted 'em & locked the nut? If you don't preload 'em, you won't get a good adjustment & they'll seem loose afterwards.

Learning more every day! Ok, so I'm gonna go ahead and ask, what's the best way to do that? I did set the lock nut, but maybe I didn't get them tight enough?

 

[TDHofstetter]

You need a torque wrench. You tighten the nut to a specified torque (Guys? Somebody help me out here with the correct torque spec for that nut?) - it's something in the vicinity of 40 foot-pounds, I think - while you turn the wheel by hand, several full revolutions, doublechecking the torque the whole time. That places a specified load on the bearings, seating 'em fully against both races.

Next, you back off the nut and torque it down again - to another, much lower torque (I need THAT torque, too, guys!), around 5 foot-pounds. Last, you back the nut off FROM THAT TORQUE SETTING a specified distance - it's usually 1/4 turn. THEN you lock the nut.

That's the procedure, but I don't have the torque specs - the ones I gave are good guesses, and should get you pretty ballparky, but I'd feel better if someone spoke up with the correct numbers.

 

[Crjcw]

Ok, that sounds simple enough. Been a long time since I've done this kind of work. Haven't had any projects in quite a while. Thanks for all the help, I really appreciate it.

 

[Old Dog]

Ok this is what chilton says to do. Torque to 50 ft. lbs. while turning the wheel by hand, than back the nut off 1/8 to 1/4 turn.
Tim you were pretty close.

If you don't have a torque wrench, what I do is tighten them till I can no longer turn the wheel with one hand, and than back it off a 1/8 of a turn or so till it turns without to much resistance. Kinda backyard, but it works for me. (I'm to lazy to go get my torque wrench out of the tool box)

 

[TDHofstetter]

That's pretty close, too.

 

[Crjcw]

Thanks guys!!