King Pin Dana 60 Death Wobble Fix!!

[FULLSIZE]

just found my DW today, looks like i'll be installing shims tomorrow. this is some good tech, thanks guys.

[Eric]

Originally posted by FULLSIZE
just found my DW today, looks like i'll be installing shims tomorrow. this is some good tech, thanks guys.

And you are going to tell us how things worked out, right?

[1tonyj]

Hey Depdog, it worked for me also, i used one 1/8 inch thick washer!

[randii]

I've seen rock buggies with the spring removed and a machined plate that takes up all the slack. I guess for a rig that doesn't see much driving you don't have to worry about the wear on cone causing slop. But having no give at the kingpin seems counter productive.
As long as you can set the bearing preload with shim packs, how would this be any different than wheel bearings, Toyota closed-knuckle trunion bearings, or heavy equipment trunion bearings?

Why did Dana elect to use a consumable puck of plastic for this application, anyway? Is the theory that it is better to smash the plastic insert instead of bending a tube? Wouldn't you wind up just smashing, THEN bending?

Yeah, I know, this only becomes an issue with bigger tires and increased leverage, but it seems like it would be nearly as cheap to insert a bearing and shims instead of plastic and spring. I guess the latter lends itself to production more easily...

Maybe some engineer bought the rights to turning out those bushings, intending to fund his retirement with future sales.

Randii

[azk5]

Originally posted by randii
I've seen rock buggies with the spring removed and a machined plate that takes up all the slack. I guess for a rig that doesn't see much driving you don't have to worry about the wear on cone causing slop. But having no give at the kingpin seems counter productive.
As long as you can set the bearing preload with shim packs, how would this be any different than wheel bearings, Toyota closed-knuckle trunion bearings, or heavy equipment trunion bearings?

Why did Dana elect to use a consumable puck of plastic for this application, anyway? Is the theory that it is better to smash the plastic insert instead of bending a tube? Wouldn't you wind up just smashing, THEN bending?


Randii

Shimming the cone bushing would be the same as a wheel bearing except for the wear factor. If you spring load the cone bushing you have a flexible impact design that can give a little instead of bending or breaking. I think this is better for big loads then ball joints or having a wheel bearing design at the knuckle. Besides the cone bushings out last the trucks they're on.

[manteca]

This is great stuff. I'm assembling my D60 right now. I plan on doing this before its even installed. But won't be able to comment on it for a another month or so because of vacation plans. Thanks for the great tech.

[AZFord4x4]

Originally posted by azk5
Besides the cone bushings out last the trucks they're on.

no kidding, I've only ever broken 1, & I found it when I snapped a steering knuckle in half, so I assume it went at this time. I just bought 3 new springs & 3 new bushings (2 for my tow rig, 1 for the 'wheeling rig since it seems to only wear out the drivers side) & cost me about about $60 for all 6 pieces. You guys are making rocket science out of a wear item that's cheap as can be, & mickey-mousing a solution that could have negative long term side effects. IIRC 1/4" spacer, & that spring isn't going to have much compression left, I don't know if it needs to have it, but since Dana did such a good job engineering the rest of the axle, I'd like to think that they knew WTF they were doing when they put that spring in there... Just my opinion though

[Shaker]

I have found on all my other 60's in the past when the death wobble shows up I just put a new spring in and it's fixed. I am doing hydro on my newest 60 now so I'll see if that acts like a "shock" to eliminate the Death Wobble.....

Might wanna check caster specs too....

[FULLSIZE]

Originally posted by Eric


And you are going to tell us how things worked out, right?

65 and no DW. i also installed a stabilizer so that might have helped also.

[Eric]

Sweet. I am glad you fixed your DW. I have had it and I have fixed it as well. Oh what a feeling to finally get it fixed.

[FULLSIZE]

Originally posted by FULLSIZE


65 and no DW. i also installed a stabilizer so that might have helped also.

just thought i'd up date this, i guess i got lucky on my test drive because for some reason its doing it again around 30mph. WTF, i guess i gotta dive back in there.................

the guy i got these tires from also had a DW problem. gonna try to switch the tires around and then check everything over again.

[Lloyd]

Originally posted by AZFord4x4
... mickey-mousing a solution that could have negative long term side effects. IIRC 1/4" spacer, & that spring isn't going to have much compression left...

Been thinking about this carefully, since my front is going back together and I'd rather not need to take it apart again. After seeing the thread yesterday about 1/2x20 threads being stripped to get a washer in (http://www.pirate4x4.com/forum/showt...hreadid=161582) I took some measurements. On my axle the nylon bushing sits flush with the top of the stress cushion on the top of the outer knuckle. This is with the bushing seated in place on top of the inner C, on the kingpin, and the bottom pulled up tight. That stamped steel spring seat, which goes between the spring and nylon bushing, is 0.055" thick; the OEM steering arm, pass. side kingpin spring cap, and my new billet hi-steer arm (Sky Mfg.) all have a spring well of 1.625" depth. I put a spring in a vise used a dial caliper to find that it has a solid height of 1.410". This means a 1/4" spacer is 0.090" too much. By jamming that much extra spacer in and cranking it down, three things can happen: 1) plastic deformation of the nylon spacer, 2) compression of the inner C, 3) outer knuckle is put in tension and stretched. Probably all of these happen to various degrees; nylon is quite strong in compression, especially when it has the radial confinement of the bore in the upper knuckle to support it. Also consider that most of the cast irons and steels have thermal expansion coefficients between 6 and 10 microinch/(inch * degree F), and take 8" through the outer knuckle; the change from 70F to -30F adds another 0.006" or so interference. On a 1-ton pickup used to haul heavy loads over mountain roads it wouldn't surprise me to see knuckle temps of 300F or more, especially after long braking downhill - perhaps this isn't the case for a dedicated trail rig, but it will still get hotter than 70F and the outer knuckle will expand some. On a 'yota knuckle where shims are used to adjust the clearance, there is excellent heat transfer between the inner and outer knuckle, due to the amount of metal in contact between them - and I'd hope that most people don't find the proper shim-pack thickness and then increase it by 3mm. On an open-knuckle 60 you have only the bottom kingpin to provide efficient heat transfer, since nylon has a very low thermal conductivity (thermal conductivities of metals are MUCH higher than polymers) and temperature differentials between the inner and outer knuckles can be expected to be much higher. IMHO putting a cast part (known to be marginal for our use - see the aftermarket knuckle thread) under this much tension and then beating on it on/offroad with big tires and thermal cycling is not the smartest idea I've seen lately.

I'll try the $5 for new springs first. A couple of people have posted that this cured their DW. IF there is a persistent DW problem with the new springs, then I may shim it - I'm sure that 44" square boggers on bent beadlocks was not a design consideration when the spring preload was determined. If I do use a shim, it won't be more than 1/8" thick. My 0.002 on D60 kingpin spring shims.

[Eric]

Good info Lloyd.

The original post on ColoradoK5.com states......

"So we take the caps off, add 3ea 1/2" fender washers above the spring on each side (this is just under 1/4" of thickness). "

I think some people have taken that to mean a 1/4" spacer is close enough.


Does anyone know the spring rate of the king pin spring?

[tj7]

hey guys,so what is the fix here slap some washers on top of the spring to make up for bigger tires ,or do what camo did and get a kinpin bearing on top.

i am in the midst or rebuilding the kingpins myself and putting all new shit in.should i just go ahead and slap washers in since ill be running 39.5's with full hydro or just keep it all stock and see what happens....

ya bastards got me all confused.....

[SHERPA]

I'm glad to see Eric's building that 60

--Sherpa

soon to be making a roadtrip to dynarape and have
my junk built....

[Eric]

Yep, getting rid of the D44.

[Blk69stang]

I had serious DW above 25mph just after my 60 install. Tossed on a steering stabilizer and shimmed the kinpin springs with 1/4" worth of washers, and so far no death wobble up to 55mph (haven't gone faster yet).

[AZFord4x4]

Originally posted by tj7
hey guys,so what is the fix here slap some washers on top of the spring to make up for bigger tires ,or do what camo did and get a kinpin bearing on top.

i am in the midst...blah blah blah...with full hydro... blah blah blah
ya bastards got me all confused.....

to my knowledge, nobody with full hydro has had a death wobble problem... the hydro pretty much kills it no matter what... I could be wrong, & I'm sure if I am someone will chime in soon.
I'd still spend the $20 or whatever on new springs just because.

I honestly don't see the point in bearings on the upper king pin. it's not like there's a hell of alot of load on that bushing/spring, the only reason I see it there is #1, to provide a pivot point (no shit huh? ) & to stablize the knuckle during any high speed vibration. Looking at the typical passenger side cap should tell you there's not a whole hell of alot of load on it (due to the barely above sheetmetal cap that typically exists) & the fact that I've pulled that cap off, full weight of the truck on the ground, & nothing moved. This leads me to belive the spring is there to absorb vibration, even of a stock 235/85-16... now you want to shim it, put a bearing in it, & run a tire that don't have a prayer of running as smooth as the worst 235.... to me I'm going to say that energy is going somewhere...

fuck, I just read that... weird rant, but I'm drinking... please forgive me, but hopefully it'll make sense to someone.

[Stephen]

I'm with the "don't fix it till it's broke" crowd. Obviously, shimming the spring too much is bad, shimming around 1/8th instead of 1/4" shouldn't hurt anything.
My K5 has always had a bit of a "bump" at DW speed (30 or so) but with the assist ram it's no big deal. With the motor not running, like if I'm being flat towed, it's violent.
So due to recent airborne stupidness, I take the springs and bushings out and find one side has a multi piece bushing and both springs are about 1/4" shorter than a new one. I "fixed" it by putting in new springs, new bushings and new spring cups. I actually used 2 spring cups to shim it a bit tighter, one top and one bottom. Result: a little hard to tell since I haven't run it without the ram but it doesn't have the bump that I could feel before. And it corrected about 1/2 of the 2" of toe out that appeared suddenly.
So, we're putting together a spring and bushing kit, it should be about $18.00 or so for spring bushing and cup for both sides. It should be a good start on every quest to end DW.

[AZFord4x4]

Originally posted by Stephen
So, we're putting together a spring and bushing kit, it should be about $18.00 or so for spring bushing and cup for both sides. It should be a good start on every quest to end DW.

Nice to see you stepping up Stephen, especially being you're talking about the kind of price I pay at the dealership at good guy prices... Then again, you've always been behind us fullsizes... I know I for one appreciate this a hell of alot (even if I still havn't seen shifters for my Ford douber )

[ROCKSFORBRAINS]

Originally posted by AZFord4x4


You guys are making rocket science out of a wear item that's cheap as can be, & mickey-mousing a solution that could have negative long term side effects. IIRC 1/4" spacer, & that spring isn't going to have much compression left, I don't know if it needs to have it, but since Dana did such a good job engineering the rest of the axle, I'd like to think that they knew WTF they were doing when they put that spring in there... Just my opinion though

I think the idea here is to use the spacers as a diagnosis aid for those who have no idea where their death wobble is coming from, and as a temporary fix for axles with old parts untill new spring and bushing can be installed. Not necessarily as a "po' man's permanent fix". sheesh.
New kingpin parts are available, as well as any other dana 60 parts, from HERE

[Lloyd]

Originally posted by Eric
Does anyone know the spring rate of the king pin spring?

I don't, and haven't been able to find it anywhere, but standing on one of my used ones compressed it about 1/4" (over 250#) so the rate has gotta be around 1000 lb/in.

[MuddMachine]

Im surprised you guys are so far behind, the Collingwood boys were onto this shit 15 years ago. Very surprising considering they spend more time on the dogsled than in thier 4x4......

[87yj38]

I tried this today on my HP60. Used a pitman arm washer from a spare box I have. Torqued down the steering arm bolts, test drove, no DW.

The thickness of the washer in question was 3/16" for future reference...

[Eric]

Originally posted by 87yj38
I tried this today on my HP60. Used a pitman arm washer from a spare box I have. Torqued down the steering arm bolts, test drove, no DW.

The thickness of the washer in question was 3/16" for future reference...

Did you have DW before you did this, or did you just do it to make sure you don't get it?