Open VS Closed Knuckles (1 Viewer)

[80t0ylc]

Did a search and couldn't come up with any serious dialog on this argument here on MUD. I've been researching it a little this A.M., and made a short list of the pluses and minuses of each.

Advantages:

Closed Knuckle
-Longer life, more durable
-smoother power transfer in turns
-Better protection from elements
Open Knuckle
-Better turning radius
-Cheaper Maintenance
-More modern design

Disadvantages:

Closed Knuckle
-More difficult maintenance
-Old, outdated, hard to get parts
-More expensive to maintain
Open Knuckle
-Exposure to elements
-Sealed lube
-Potentially jerky power transfer in turns

I was looking at my bother in law’s 2006 Super Duty front end recently, which had the open knuckle design and the argument was forming in my head, since being a cruiser head, why would a heavy duty front end be an open design? Aren’t Rockwells closed design? Has anybody got any specific examples of where a closed knuckle is superior. Trail experiences or carnage suffered due to a failure? We all wheel from time to time with other persuasions and I just want to open this thread to all comers. Jeep forums just ooze with how superior the open knuckle is and how antiquated our closed knuckles are. Just trying to get ya started – lets here it – what’s your opinion or experience?

 

[blzrfn]

chat?

 

[Tapage]

closed knuckle .. debatable the item about easy access .. just easy inspection uf you are breaking things .. as usuall in J**ps ..

 

[80t0ylc]

chat?

How is this more "chatty" than say:
https://forum.ih8mud.com/80-series-tech/165227-wild-wheeling-videos.html
Which BTW has existed on this "tech" forum for 2 years?

or
https://forum.ih8mud.com/80-series-tech/57788-wild-wheeling-pics.html
Which has been on tech for 4 years?

or someone painting their truck and showing it off with pics, or asking someone to check out an 80 for them because their interested to buy it in a town across the country? This is a technical subject and has merit to be here whether you approve or not. If you have something to contribute to the subject, do it - by all means. Otherwise, leave it to the moderators to decide.

 

[blzrfn]

I'm not trying to argue with you, but you would probably get a lot more responses in chat because this isn't an 80 specific discussion, it is a very general 4x4 question posted in the 80 forum. Both of your links are specific to the 80 so they do kind of fit in here. Try asking the same in chat and I bet you get twice the response (by my count that would be at least 2).

 

[firetruck41]

How is this more "chatty" than say:
https://forum.ih8mud.com/80-series-tech/165227-wild-wheeling-videos.html
Which BTW has existed on this "tech" forum for 2 years?

or
https://forum.ih8mud.com/80-series-tech/57788-wild-wheeling-pics.html
Which has been on tech for 4 years?

or someone painting their truck and showing it off with pics, or asking someone to check out an 80 for them because their interested to buy it in a town across the country? This is a technical subject and has merit to be here whether you approve or not. If you have something to contribute to the subject, do it - by all means. Otherwise, leave it to the moderators to decide.

Sometimes things stay in tech, sometimes they don't. There doesn't seem to be any connection to 80 series tech, in this thread, but that is for a mod to decide. All I know, is I am happy with my closed knuckles.

 

[LandCrusher'70]

How is this more "chatty" than say:
https://forum.ih8mud.com/80-series-tech/165227-wild-wheeling-videos.html
Which BTW has existed on this "tech" forum for 2 years?

or
https://forum.ih8mud.com/80-series-tech/57788-wild-wheeling-pics.html
Which has been on tech for 4 years?

or someone painting their truck and showing it off with pics, or asking someone to check out an 80 for them because their interested to buy it in a town across the country? This is a technical subject and has merit to be here whether you approve or not. If you have something to contribute to the subject, do it - by all means. Otherwise, leave it to the moderators to decide.

Those threads are all 80 series related.

This topic is quite general. Not 80 series specific.



Are you asking because you are looking into a swap (i.e.: tech)? Or just looking for a debate (i.e.: chat)?

 

[80t0ylc]

No worries! I asked the moderator to move to chat.The 80 series was made with closed knuckle, right. I'm not interested in a debate. Just looking for some input from people who've seen good or bad from closed and open. Things to make us all a little sharper when some jeeper says: "Hey, what're ya still running them closed knuckles for?" Maybe even learn something. Sounds like "tech" to me, but I guess it must be otherwise- most comments so far have been consistent: too general or this is chat material. Fine, I don't care - move the thread to chat already!

 

[reffug]

Tech not chat and it stays put IMHO...................

If you have something to add to the debate please feel free to do so.

 

[Romer]

chat?

Nope not chat

 

[80t0ylc]

Thanks mods!!

It would seem to me that these open knuckle joints would have an extremely short life, being permanently lubed. The stress would have to be more than a typical u-joint since they're handling torque through a wider angle of movement. Maybe their saving grace is that a lot of applications are on part time set ups, unlike our full time 80s. And they're only handling torque to 1 wheel as opposed to a drive line u-joint, which would be supplying an axle. But, they're also exposed to the elements, a variable not easy to control or predict. I would imagine they'd have a high trail failure rate, such as: you get to your trail, engage 4WD and then find you got problems. If you're lucky the problem shows up immediately, before you're too far out on the trail where recovery problems get serious.

 

[PhrogsPhorever]

Lets get this back on track and swerve from the HTTTs chat envy

Those dis-advantages on the standard knuckle are debatable.

Difficult maintenance? you can DIY a knuckle re-build rather quickly if you know what you are doing or have at least seen it done, I just re-built my 40 knuckles and it took about 6 hours (with a few beer breaks). Aside from the 54mm hub socket, there aren't any crazy tools needed that your average shade-tree mechanic wouldn't have. I agree that an open would, be easier, but barring a catastrophic failure, maintaining a Yota knuckle is not all that bad I always thought that doing a knuckle service and bearing swap would suck until I actually did one, and it really doesn't

As far as outdated parts, the 80 series stuff is still readily availible. Now mind you, if you no-s*** broke a knuckle housing or break a knuckle arm, that might be hard to find, but all the spindles, bearings, seals, shafts, birfs, nuts and bolts are readily availible from either the great vendors here on Mud or from Mr. Yota via CDan

More expensive to maintain? Bearings are cheap, grease is cheap, seals are kinda cheap. The only big ticket items that will break will be an axle shaft or birf, but I assume you are talking maintenance cost, not catastrophic failures. A full knuckle rebuilt kit with Koyo trunnion and wheel bearings is $170 from Kurt. That and a few cans of red grease ($6-7 a piece) and you are in business for under $200, some tools, and a few hours of your time.

Also, can you modify an 80-series axle to do that, or would you have to swap in a new front axle? That right there might not make it worth the cost and effort to switch.

My $0.02

-More difficult maintenance
-Old, outdated, hard to get parts
-More expensive to maintain

 

[80t0ylc]

These dis-advantages are debatable.

Disadvantages:

Closed Knuckle
-More difficult maintenance
-Old, outdated, hard to get parts
-More expensive to maintain

Edit: BTW this is general consensus, not my opinion. Failure rate was not an addressed or measured item except for being an advantage of closed knuckles. Seems like joint life should be an indicator that closed would be desirable.

In my research, open knuckle = sealed joints = no maintenance. No maintenance is generally easier.

All early Jeep front axles were closed knuckle. Parts for most closed knuckle, outside of Toyota, are at best difficult to get. Today very few, if any, production made vehicles are using closed knuckle.

And lastly, any maintenance was considered more expensive than no maintenance.

Personally, I prefer the closed knuckle for a expedition type rig, like my 80. It takes time and effort to do the maintenance, but you are more aware of the condition of your rig if done properly. IMHO, for daily drivers and grocery getters, sealed joints and open knuckles might make sense. But not for the way most of us use our 80.

 

[PhrogsPhorever]

It is an interesting angle to knuckle maintenance I must agree But, even with sealed CV style joints, they all need service at some point, so saying no maintenance is needed is not exactly true. My Tacoma has a sealed axle shaft and joint set, but it needs service at some point.

But, the external drive shaft steering joint designs seem mostly to be on IFS trucks, and the closed style seemt to be on SA trucks

 

[80t0ylc]

.......But, the external drive shaft steering joint designs seem to be on IFS trucks, and the closed style seemt to be on SA trucks.......

My brother-in-law's 2006 Ford Super Duty F250 has a solid front axle with open knuckles. No rubber boot is covering the CV or u-joints on the axle ends. The joints are exposed and not serviceable. They replace them as part of the inner axle assembly. Of course it's a part time set up. Don't know about GM or Dodge, but that seems to be the direction the industry is going. Next time you see any late model solid axle front end rig of any size in a parking lot, check it out. Unless it has Rockwells, and if it's stock, I can almost guarantee it'll be open knuckle.

 

[-Spike-]

Unless you happen to be lucky enough to see a new solid axle Toyota, of course. Or Nissan, I suppose.

The others use the open style because it's cheaper, I'll bet.

 

[PhrogsPhorever]

The new Hilux at the SEMA show with the solid axle was pretty sweet. Too bad we will never see it in the US

Unless you happen to be lucky enough to see a new solid axle Toyota, of course. Or Nissan, I suppose.

 

[unwiredadventures]

The new Hilux at the SEMA show with the solid axle was pretty sweet. Too bad we will never see it in the US

ARAIK, that was a one off vehicle. I don't think it's going into production anywhere.

 

[dogcatch'n]

I'm not trying to argue with you, but you would probably get a lot more responses in chat because this isn't an 80 specific discussion, it is a very general 4x4 question posted in the 80 forum. Both of your links are specific to the 80 so they do kind of fit in here. Try asking the same in chat and I bet you get twice the response (by my count that would be at least 2).

x2.....

 

[PhrogsPhorever]

ARAIK, that was a one off vehicle. I don't think it's going into production anywhere.

We can hope and dream