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3.5" or 4" tube for front steering 14 bolt?

Pender1

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I'm looking into the possibility of building a front 14 bolt for my K5, but one of many questions I've come up with is should I use 3.5" or 4" tubing? Is there some big disadvantage to going bigger?

Busted Knuckle and WOD appear to use 3.5" OD .5" wall and ECGS lists 4" OD .5" wall. These are both places I'd trust to buy from, so I'm curious about the difference without much of a difference in price. Any input?
 
If you're even asking, go 4", although 4" x0.500 seems ridiculous, will they do 375?

Assuming K5 means pass drop, I'd be weary of a pass drop 14b front. rockyota83 did one and I remember him saying it was kinda fucked because the driveshaft ends up under the oil pan.
 
If you're even asking, go 4", although 4" x0.500 seems ridiculous, will they do 375?

Assuming K5 means pass drop, I'd be weary of a pass drop 14b front. rockyota83 did one and I remember him saying it was kinda fucked because the driveshaft ends up under the oil pan.

From the interviews I've heard with Jake Burkey, Busted Knuckle knows a lot that I don't about axles. Just curious why the one outlier does it with 4". I'm probably going to go driver drop and put in a different transfer case to get there. My NP208 isn't going to like what I'm going to do to it with an LS and big tires. I'm definitely under-educated about axle building, but I'm building one anyways. Got to learn somehow and I need something to do after I finish my drivetrain swap.
 
From the interviews I've heard with Jake Burkey, Busted Knuckle knows a lot that I don't about axles. Just curious why the one outlier does it with 4". I'm probably going to go driver drop and put in a different transfer case to get there. My NP208 isn't going to like what I'm going to do to it with an LS and big tires. I'm definitely under-educated about axle building, but I'm building one anyways. Got to learn somehow and I need something to do after I finish my drivetrain swap.

My point is, if they're the same price, just go with the beefier one. Who cares if one is enough or not :flipoff2:​​​​​​


I'd bet the 3.5" will be fine, especially being 500 wall. But, you know, there's no kill like overkill :smokin:
 
What is diameter of bore in the center section? That is your answer.
 
Doing 14b front, my choice would be which allows 40 spline shaft.
 
Was pretty clear, the bore hole the tube fits in, if its a 3.5" bore that means a 4" tube has to be transitioned down to fit. Why bother with 4" , unless bore is the same?
 
Was pretty clear, the bore hole the tube fits in, if its a 3.5" bore that means a 4" tube has to be transitioned down to fit. Why bother with 4" , unless bore is the same?

There are newer 4" tube 14b castings, I'm 99% sure that's what ecgs is using.
 
Assuming K5 means pass drop, I'd be weary of a pass drop 14b front. rockyota83 did one and I remember him saying it was kinda fucked because the driveshaft ends up under the oil pan.


correct, especially with leafs. 14b front much better off on the driver side because of how offset the pinion is
 
Things like the weight of your rig, tire size, and usage will be important for giving you a considered answer, but I am guessing since you are talking about a K5, a 14 bolt front is already overkill regardless of tube size. It sounds like you are trying to build a 10,000Lb pig that can't climb for shit, so fuck it, go for 4" tubes so your axle weighs 700Lbs.

If it were me, and for whatever reason, I just HAD to have a 14 bolt front, I would almost certainly go with the 3.5" tube. More clearance and less weight, but then again, going with a 14 bolt is like saying you don't give a shit about either :laughing:


Also, I seriously doubt you are going to be time, money, or any realizable strength ahead going with a custom 14 bolt front instead of a Super 60 or a regular Superduty 60 with the 10" gears and 1550 shafts. Sure, the 14 bolt has a 3rd pinion bearing and a .5" larger ring gear, but you will be running on the coast side of the gear, so I doubt it is actually much stronger than the 10" high pinion Super 60 gears.
 
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Things like the weight of your rig, tire size, and usage will be important for giving you a considered answer, but I am guessing since you are talking about a K5, a 14 bolt front is already overkill regardless of tube size. It sounds like you are trying to build a 10,000Lb pig that can't climb for shit, so fuck it, go for 4" tubes so your axle weighs 700Lbs.

If it were me, and for whatever reason, I just HAD to have a 14 bolt front, I would almost certainly go with the 3.5" tube. More clearance and less weight, but then again, going with a 14 bolt is like saying you don't give a shit about either :laughing:


Also, I seriously doubt you are going to be time, money, or any realizable strength ahead going with a custom 14 bolt front instead of a Super 60 or a regular Superduty 60 with the 10" gears and 1550 shafts. Sure, the 14 bolt has a 3rd pinion bearing and a .5" larger ring gear, but you will be running on the coast side of the gear, so I doubt it is actually much stronger than the 10" high pinion Super 60 gears.

Bring the hate! Let it flow! :rolleyes:​​​​​​

3.5x500 is 16 lbs/ft, 4x500 is 18.7 lbt/ft. So we're talking about a ~16 lb weight penalty for the 4". Nice try though.

Do you really think a super 60 center is going to be soooo much lighter than a 14b? Because those aren't exactly light either.

Ring gear diameter isn't everything. The pinion splines on a D60 aren't even close to the diameter as a 14b.

But I guess all these 1000 hp rock bouncers beating on their rig every weekend should have just used a stock super 60 :rolleyes:
 
Bring the hate! Let it flow! :rolleyes:​​​​​​

3.5x500 is 16 lbs/ft, 4x500 is 18.7 lbt/ft. So we're talking about a ~16 lb weight penalty for the 4". Nice try though.

Do you really think a super 60 center is going to be soooo much lighter than a 14b? Because those aren't exactly light either.

Ring gear diameter isn't everything. The pinion splines on a D60 aren't even close to the diameter as a 14b.

But I guess all these 1000 hp rock bouncers beating on their rig every weekend should have just used a stock super 60 :rolleyes:

My point was that the weight adds up. Overkill for the sake of overkill is stupid, and starts a snowball effect that is somewhat of a vicious cycle. You are right, 16 Lbs. isn't going to make or break the rig, but it is a fair amount of unsprung weight that is unnecessary if you care about your rig riding somewhat nice, and the ground clearance isn't much worse than a 3.5" tube, but it is worse. 3.5" .5" wall tube is pretty damn stout, so why go to 4" and add weight and lose clearance if you don't need it?

I don't get where you think I was claiming a Super 60 was lighter; I was just stating that a Super 60 or a Dana 60 with the super 60 gear set and 1550 shafts is about the same strength, cheap, and not 100% custom. I don't think a custom 14 bolt front end is worth it in the OP's application, but then again, he gave us no details on what his application really is other than a K5.

There is a huge difference between a 1,000 HP rock bouncer and a K5 trail rig.
 
My point was that the weight adds up. Overkill for the sake of overkill is stupid, and starts a snowball effect that is somewhat of a vicious cycle. You are right, 16 Lbs. isn't going to make or break the rig, but it is a fair amount of unsprung weight that is unnecessary if you care about your rig riding somewhat nice, and the ground clearance isn't much worse than a 3.5" tube, but it is worse. 3.5" .5" wall tube is pretty damn stout, so why go to 4" and add weight and lose clearance if you don't need it?

I don't get where you think I was claiming a Super 60 was lighter; I was just stating that a Super 60 or a Dana 60 with the super 60 gear set and 1550 shafts is about the same strength, cheap, and not 100% custom. I don't think a custom 14 bolt front end is worth it in the OP's application, but then again, he gave us no details on what his application really is other than a K5.

There is a huge difference between a 1,000 HP rock bouncer and a K5 trail rig.

You're reading into K5 way too much. Could be really anything from a trail rig to a buggy with Blazer grille a fenders.

If you're going to add weight anywhere, the front axle is probably the best place. How many guys fill their front tires full of water on hardcore rigs?

I'm a big fan of the 05+ axles, but he may just want to start new. The possibilities are endless, he could do 05+ BJ outters with big bell rcv's, or even go to the ried super kingpin outters. He may want a custom width as well.

If I was building a 14b front, It would mean I was trying to build a bullet proof as possible axle, and I'd want 4" tubes if that was an option. I do think the 500 wall in 4" is excessive, I'd go for 4" 375 which is lighter than 3.5x500 and probably stronger.
 
My point was that the weight adds up. Overkill for the sake of overkill is stupid, and starts a snowball effect that is somewhat of a vicious cycle. You are right, 16 Lbs. isn't going to make or break the rig, but it is a fair amount of unsprung weight that is unnecessary if you care about your rig riding somewhat nice, and the ground clearance isn't much worse than a 3.5" tube, but it is worse. 3.5" .5" wall tube is pretty damn stout, so why go to 4" and add weight and lose clearance if you don't need it?

I don't get where you think I was claiming a Super 60 was lighter; I was just stating that a Super 60 or a Dana 60 with the super 60 gear set and 1550 shafts is about the same strength, cheap, and not 100% custom. I don't think a custom 14 bolt front end is worth it in the OP's application, but then again, he gave us no details on what his application really is other than a K5.

There is a huge difference between a 1,000 HP rock bouncer and a K5 trail rig.

You're not wrong. Weight does add up, but I think you'd have a hard time showing where the difference in a 05+ SD60 and a 14 bolt with the 05+ outers is going to matter much. 600lbs is 600lbs, doesn't matter which housing it's built on. The amount of mud stuck to my tire will matter more than weight of the tubes.

Ground clearance is a bit worse with 4" tube, but you're seriously splitting hairs. .25" is the difference of which side of your truck the sun was heating up in the parking lot. If you drag by .25", just use more skinny pedal.

I'll admit, I don't need a steering 14 bolt at this point, but I have a C&C 14 bolt sitting in my yard and I like learning how to build things and I have no idea where this rig is going to end up, it just keeps evolving. Worst case, I'll sell it and buy a 60 later. You sound about as much fun as a wet blanket. I deeply apologize for building something that you don't like.
 
You're reading into K5 way too much. Could be really anything from a trail rig to a buggy with Blazer grille a fenders.

If you're going to add weight anywhere, the front axle is probably the best place. How many guys fill their front tires full of water on hardcore rigs?

I'm a big fan of the 05+ axles, but he may just want to start new. The possibilities are endless, he could do 05+ BJ outters with big bell rcv's, or even go to the ried super kingpin outters. He may want a custom width as well.

If I was building a 14b front, It would mean I was trying to build a bullet proof as possible axle, and I'd want 4" tubes if that was an option. I do think the 500 wall in 4" is excessive, I'd go for 4" 375 which is lighter than 3.5x500 and probably stronger.

It's a trail rig for now, but there's no end goal in sight. I'm just going to keep building on it as I go. The 05+ axles are pretty stout units on their own and are probably plenty for my current needs, but if I'm going to do any upgrading to one I'm in roughly the same money to have a 14bolt and then I've got common gears, covers, bearings, etc.

If you assume a cantilevered load: 4" .375wall is roughly 80% stronger than 3.5" .5wall. 4".5wall is roughly 150% stronger than 3.5" .5wall. The .375"wall isn't a bad option at all.

Basically I'm wanting to build one because I can. Need or not was never a concern. Thanks for the input.
 
You're not wrong. Weight does add up, but I think you'd have a hard time showing where the difference in a 05+ SD60 and a 14 bolt with the 05+ outers is going to matter much. 600lbs is 600lbs, doesn't matter which housing it's built on. The amount of mud stuck to my tire will matter more than weight of the tubes.

Ground clearance is a bit worse with 4" tube, but you're seriously splitting hairs. .25" is the difference of which side of your truck the sun was heating up in the parking lot. If you drag by .25", just use more skinny pedal.

I'll admit, I don't need a steering 14 bolt at this point, but I have a C&C 14 bolt sitting in my yard and I like learning how to build things and I have no idea where this rig is going to end up, it just keeps evolving. Worst case, I'll sell it and buy a 60 later. You sound about as much fun as a wet blanket. I deeply apologize for building something that you don't like.

I see reading comprehension is not your strong suit. Never did I claim or imply a Super 60 would be any lighter than steering 14 bolt. I brought it up as an economics argument against a 14 bolt steer axle since they are plentiful, cheap, not something completely custom that you'll have trouble getting parts for, and about the same strength as what you are talking about doing.

You are the one asking dumbass questions in the hardcore tech forum and not giving any background information for someone to give you a decent answer. What do you want people to tell you besides trying to stroke your ego about what a badass you are because you are thinking about building a 14 bolt steer axle? It is not that hard to figure out the weight difference, clearance difference, or strength difference, so what kind of response are you really looking for here?

I don't care if you want to build a 10,000Lb Blazer that can't climb for shit, have at it.
 
Doing 14b front, my choice would be which allows 40 spline shaft.

I missed this the first read through. Busted knuckle offers a 40 spline option on a 3.5" tube, so I don't think that's a limiting factor. I think the issues there are more related to the knuckles and inner C.
 
if you dont care then why are you replying? :homer: youre just mad you were flat wrong about 4" tube being way heavier then 3.5" :laughing: :flipoff2:

He asked a question (even though it seems his mind was already made up before he asked it) and I gave him an answer. What he chooses to do with that information is not my concern. It is pretty much the old leading a horse to water proverb. I ultimately don't care whether he goes with 4" or 3.5", I was just defending my opinion.


I don't know how you think I was "flat wrong" either. I said 4" tube would be unnecessary weight and have less clearance; both true statements. Whether you think 16 Lbs. and 1/4" less clearance is significant enough to sway your decision is up to you. I'd assume it would be more expensive to go with 4" tubes (the tubes themselves should be more expensive at a minimum), so why would you pay more for more weight and less clearance if you don't actually need the additional strength? Regardless, the tube size by itself isn't going to make a noticeable difference in the way his rig will perform so this is all kind of a silly discussion anyway. I was promoting the philosophy of "right-sizing" components for maximum performance.
 
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As mentioned, the 05+ 60 is hard to beat cost to strength.

HP is always better 100% of the time. You know like when you have to reverse :flipoff2:

14b is pretty damn proven to be just about indestructible, even with big ass 40/47 spline Rockwell rcv's that some are running. If dude wants to build one, why try to talk him into something else?

OP go 4" because they don't offer 4.5" :flipoff2:
 
All this debate and no mention of a truss. Tube size might make it 100% stronger but a truss can make it 1000% stronger for the same amount of weight as bumping up the tube size. Jake Burkey from Busted Knuckle started using 3" x 2" rectangle tube with diagonals to triangulate between the axle and truss and the truss spans from C to C. Its an awesome design! Wonder where he borrowed the idea from?

BK.png


JF.jpg
 
All this debate and no mention of a truss. Tube size might make it 100% stronger but a truss can make it 1000% stronger for the same amount of weight as bumping up the tube size. Jake Burkey from Busted Knuckle started using 3" x 2" rectangle tube with diagonals to triangulate between the axle and truss and the truss spans from C to C. Its an awesome design! Wonder where he borrowed the idea from?

My buddy and I built trusses like that 12 years ago :flipoff2:​​​​​​

Trusses can be hard to package when not building a full buggy. My current rig is getting a 3link, with panhard and a steering box. I opted out of a truss for packaging. I'm also not going to be rock bouncing or desert racing.

I still like the 4x375, lighter and stronger than 3.5x500
 
My buddy and I built trusses like that 12 years ago :flipoff2:​​​​​​

Trusses can be hard to package when not building a full buggy. My current rig is getting a 3link, with panhard and a steering box. I opted out of a truss for packaging. I'm also not going to be rock bouncing or desert racing.

I still like the 4x375, lighter and stronger than 3.5x500

The Super 60 really didn't need a truss for what I will be doing to it.
F550 front 60 has a 6000 lb GAWR gross axle weight rating.
F250 front 60 is 4400 lb GAWR.
F250 rear Sterling 10.5 is 6100 GAWR.
The truss is more of a way to mount the upper links and have something to hold the steering cylinder and something for the bump stops to land on.
When I was researching for ideas on trusses I went way back in the day, that is probably why it resembles something that was built in a driveway with a 4" angle grinder and chalk sketches on the cement. It is simple yet accomplishes all of its functions.
 
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Don't get me wrong, I like it, especially the way the upper links are mounted. But I doubt BK copied you :flipoff2:​​​​​​

I'm not against trusses either, obviously they have a huge advantage adding strength vs just using massive axle tubes. Even 3.5x500 is pretty heavy for most of us. One thing a lot of people overlook is having the truss either taper off, and/or go all the way to the end of the tubes.

The jeep I'm building for my FIL has a 14b rear with an artec top and back truss. Obviously it's not going to bend, but I have to wonder if being that ridgid will put more stress on the spindle since the is no flex in the tube?
 
Don't get me wrong, I like it, especially the way the upper links are mounted. But I doubt BK copied you :flipoff2:​​​​​​

“For substantially all ideas are second-hand, consciously and unconsciously drawn from a million outside sources, and daily use by the garnerer with a pride and satisfaction born of the superstition that he originated them; whereas there is not a rag of originality about them anywhere except the little discoloration they get from his mental and moral calibre and his temperament, and which is revealed in characteristics of phrasing.”
Mark Twain


When artists copy, they remain happily unaware that they have borrowed thoughts and ideas, because they discount how much they are affected by external factors, even if those factors are not present when they sit down to create.

I don't know and have zero proof if BK saw my truss before he started making them that way or if we both ended up with a similar design, either way I am happy to know that it is a proven design as his are out in heavy use while mine has been in the garage the last two years. As I said earlier, I have been influenced by everyone. The upper link mounts and the link geometry were heavily influenced by Goat Built as he runs the bolts vertical and I am running the Goat Built lower link mounts and subframe. Like you said earlier, rectangle tube trusses date back to the days shortly after cavemen invented the wheel.

You mentioned the Artec truss top and back. Seems like everyone and their brother is making a laser cut truss these days. One thing I noticed was how much weight these things add. They are using some thick plate and alot of it and at some point the truss and steering mount and skid plates start weighing more than the original axle housing.

There are multiple axle builders that continue to use round tube with their fabricated diff housing then wrap the tube almost all the way out to the hub with plate work. Then the square hub or fabricated C is machined round so it can accept the tube. End result is a weak link about 2"- 6" long on each side that also doesn't look good because of the transition. With the tools these manufacturers are already using, there is no reason to keep using round tube as a foundation for plate fabricated housings. I am predicting you will start seeing round tube disappearing on the high dollar axles and everything will be either plate or billet.
 
I didn't buy or chose the trusses. They came with the Jeep.

3/8 too plate with 1/4 webbing is to thick imo.

Ruffstuff uses 3/16 in a box shape.
 
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