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Who'd gone to 40's and has Trussed etc their axles?

caryt

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Also actually play in the rocks. JT's heavy 7500lbs + majority is on the back axle.
I can move into gears, 4.56 and trussing both axles for about $4100 plus I'll install RCV's that that I've had a couple of years sitting in the box.
If I go this route I'll go to 40's either MT's or another set of TG's.
I am hoping this will hold up knowing that ball joint and unit bearing weakness will be a weak point.
Aftermarket BJ's can be done latter.

I hate to waste $ doing this then still have front axle issues/housing breakage.

So asking those that have done this how it work for you.
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RCVs are a good way to go to avoid too many problems. Depending on model, either reinforce the knuckles or pick up some heavier duty ones. Artec makes some good gussets for the aluminum knuckles. I have those on and they are solid. Not running 40’s though. Ball joints will need done sooner rather than later if you’re still on stock units. Probably want to look into brakes as well. Heavier tires and more stopping distance and all that. Especially in the rocks or on rocky terrain. Brake fade/failure usually ends very badly when boulders are involved.
 

fourfa

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It’s diesel so comes with steel knuckles already

How hard do you want to go? I ran the Rubicon in my JTRD with Alu-Cab, 37s, 3.5” lift springs. I was on the belly a lot (NVM skids with UHMW) but it didn’t seem to be a problem

Not trying to say you don’t need trusses etc, but it might help to clarify the issue since you’ll get a lot of comments from people who run 4 and 5 rated trails, don’t notice this is the diesel section, and don’t really read your post closely
 
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caryt

caryt

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The hardest trails I would run would be Rubicon, Slickrock, Dear valley etc. I've been on all many times with LJ's, and 4 door JK's. Desert trails and easier mountain trails exploration going solo.

I usually build with one tons and try to bullet proof my builds. Like to see if this would be enough to get by without dropping another 25k in this.
 

BlueScapegoat

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Probably repeating a lot that you already know and maybe dancing all around your question without a really helpful answer but this is a forum, so fuck it, these are my general experiences and thoughts having gone down this path recently.

I did Moab last fall, tackled the trifecta, Hell's Revenge, Fins, Elephant hill, etc, but skipped Pritchett since we were solo. That was on 40s, 3.73s, RCV fronts, Dynatrac ball joints, Spicer Chromo rears, and PSC hydro assist. Those trails are so grippy though, it was really very drama free. Either way, no problems.

This winter I did some more upgrades, as I was planning a longer wheeling trip that includes the Rubicon this spring.

So since then I've installed 4.88s, trussed and gusseted the front, front lower control arm skids. The front axle is as built as I think it can be, within reason. The rear axle I've gone with an off-the-shelf triangulated upper setup, so it's not quite a proper truss. I already had this in Moab as well. It's welded onto the tubes on each side of the center section but it just bolts into 4 existing stanchions you drill and tap in the upper part of the center cast section. So it probably helps with axle flex overall but a proper truss would be better. If you're keeping it 5 link in the rear a proper weld in truss would be the way to go. In fact, I've got one in my garage I purchased before I decided to go 4 link. I might still weld up a custom truss at some point so I can install straight upper arms in the rear but then I'm shaving the frame side brackets as well. Just didn't feel like getting into that right now. But pretty good chance that'll be happening soon.

For the RCVs in the front I opted to retain the FAD functionality, I think the street benefits outweigh the cons given the axle already has the cast FAD section. Not having a FAD housing at all would be preferable but since it's there I'm going to make use of it. The Artec front truss fully bridges the FAD housing, and the RCV kit comes with the inner shaft and a new stronger collar as well. I installed an Artec FAD skid as well just to prevent direct impacts to the casting.

I think bolt on control arm skids are kind of stupid but several people make weld-on lower skids for the front control arms where it matters, that tuck into the existing mounts and don't hurt clearance. Huge fan of those on any rig I wheel.

IMO the factory twin piston brakes are enough for the 40s. If you really want to upgrade to anything worth upgrading to you really need wheels larger than 17s and that's where I think you start getting into the slippery slope of "do I just go to bigger axles, then?"

I can say I wouldn't wheel a diesel Gladiator on 40s without hydro assist. I did Mesabi Mountain Trail up here in MN with just a steering stabilizer and there were multiple points where I COULD NOT turn the wheel. With 37s it wasn't a problem. But with 40s, and especially if you're going to air down and play in the rocks, I think a hydro assist is a non-negotiable.

Lastly I did all the labor myself. I don't know if I could justify the cost of all this work if I was paying somebody else to do it. I think that's really when you need to ask yourself if it's worth it or if you should just buy some bigger axles and bolt them in in a weekend. It's a lot of money to sink into axles as a bit of an experiment. Do I think they're strong enough for what I do? Yes. Could I beat on it more with a 60 in the front and an 80 in the rear? Yes. Would the steering geometry be way better for 40s if the axles themselves were a couple inches wider? Very yes.

So you said $4100 for gears and truss, I'm guessing that's paying somebody to install them, otherwise it's really high. But also add in the ball joints you said you haven't done yet, and a hydro assist if you don't have it. (which is a bear of an installation on the diesel.) I'll assume you already have beefy steering, but if not, you need that as well. That's your real price, imo.

Last I weighed my Jeep it sat at 6150 lbs empty. That was before I've done a bunch of work and I'm swapping bumpers here soon. I suspect it's going to end up closer to 6500 lbs. 7500 is a real chonker.

Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? 461977-2fa67e157a12046160d73b1a87bb8366_

Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? PXL_20260408_131020242.NIGHT
Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? PXL_20260408_131127947
Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? PXL_20260408_131140020
Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? PXL_20260408_131112192
Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? PXL_20260408_131102557
Jeep Gladiator Who'd gone to 40's and has Trussed etc their axles? PXL_20260408_131042448.NIGHT
 
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caryt

caryt

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Thanks great info. I buy wholesale, those are Dana gears and full install kits, my RCV's retain the FAD. All would be pro welded everything removed cleaned Tig'd on in a jig pre and post heated etc. Gears then installed. I will R&R the assembles in my shop.
 

BlueScapegoat

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Thanks great info. I buy wholesale, those are Dana gears and full install kits, my RCV's retain the FAD. All would be pro welded everything removed cleaned Tig'd on in a jig pre and post heated etc. Gears then installed. I will R&R the assembles in my shop.
Sounds like a good deal for the work they're doing. I just can't swallow paying somebody to do that stuff, myself. So I used a big ass propane torch and a mig welder. Came out straight enough, anyway. :CWL:

I also used Dana gears and master rebuild kits. I mentioned it elsewhere but having an extra carrier shim pack from another manufacturer on hand would have made installation way easier. The shims selection included with my Dana kits was poor.

It's just, I think, the make or break difference between building axles or getting complete assemblies. How much labor costs. Because I always hear people repeat that it ends up costing the same to build axles as it does to buy 60s and sell the 44s but the truth is if you do it yourself the cost is WAY lower to build the axles. And about the only other positive being you end up with a smidge more ground clearance than going to a bigger axle. But if you're paying labor it's going to cost A LOT more to have a bunch of work done than just swapping axles.

Generally I don't think it's worth it if you're paying labor.
 
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BlueScapegoat

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Also actually play in the rocks. JT's heavy 7500lbs + majority is on the back axle.
Curious what your 50/50 is
 
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caryt

caryt

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Curious what your 50/50 is
I need to get a update as I've added more weight. This is daily driver weight no water. propane food, extra gear etc and no driver.

Front 3340 rear 3670

Before I added a winch and the camper gear it was Front 3370 and 2600.
 

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I’m in your same position now and moving to tons. On the stock axles, I trussed front and rear, initially on 5:38 gears and 40” tires. RCV’s up front, upgraded steering, no hydro assist. I cannot turn the steering at all when playing. Also threw in 1350 tom woods drive shafts. had a shop tell me the rear stock shafts should be good….so didn’t plan to upgrade those.

Ran quite a few trails leading up to Moab last year for EJS.

At EJS, ran a ton of trails with the week ending on hells revenge. I think somewhere along the way I damaged the front R&P as I started popping front ring gear teeth. I wasn’t even getting on it. Very distinct sound as they get popped loose!

Got home and re-geared to 4:88’s. Bought the hydro assist, didn’t get it installed in time.

this years EJS…I stepped up a bit more, steel bender, metal masher, Kane creek and capped the week off with cliffhanger and Pritchett.

I took it easy leading up to cliffhanger and Pritchett, 1 attempt and then pull the winch cable. I continued the same philosophy on those two as well. Didn’t help, as I ate the pass side rear axle shaft. On the drivers, she twisted up pretty good. Looks like the R&P survived. I knew I was gambling with my trip and the trails I was on, I get it.

I hate being broke and not having a plan. So 1 tons it is. The weight of the vehicle, 40’s and playing in the rocks, bad combo for the D44’s and the JT.

for those on D44’s I’d look at getting a set of rear axle shafts as spares. Stocks appear to be on B/O and other companies are weeks out. I was able to get a revolution pass side rear at the vendor show, by luck. It was there display axle. I also ordered a set of Yukons as those appear to be available, hoping to get them next day. So I could go play one more time. The drivers side revolution is also in route. So I’ll have the yukon’s as spares.

I’ll be honest, I’m a bit concerned about the upgraded shafts in the rear eating the R&P, so will see. Upgrading components leads to the next weaker link in the chain. Maybe should have stayed with 1310 drive shafts. Thats easier to fix than where I’m at now.

have the rubicon planned for September and not sure I’ll have the tons in yet. So I’m sure we will push the D44’s one more time!

I am building my 1 tons, pulled a set of 2010 super duty axles. Starting the prep this weekend, at least that’s the plan. It’s way cheaper than crate axles!
 
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caryt

caryt

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Great info, keep us informed on the SD build up!
 

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I’m in your same position now and moving to tons. On the stock axles, I trussed front and rear, initially on 5:38 gears and 40” tires. RCV’s up front, upgraded steering, no hydro assist. I cannot turn the steering at all when playing. Also threw in 1350 tom woods drive shafts. had a shop tell me the rear stock shafts should be good….so didn’t plan to upgrade those.

Ran quite a few trails leading up to Moab last year for EJS.

At EJS, ran a ton of trails with the week ending on hells revenge. I think somewhere along the way I damaged the front R&P as I started popping front ring gear teeth. I wasn’t even getting on it. Very distinct sound as they get popped loose!

Got home and re-geared to 4:88’s. Bought the hydro assist, didn’t get it installed in time.

this years EJS…I stepped up a bit more, steel bender, metal masher, Kane creek and capped the week off with cliffhanger and Pritchett.

I took it easy leading up to cliffhanger and Pritchett, 1 attempt and then pull the winch cable. I continued the same philosophy on those two as well. Didn’t help, as I ate the pass side rear axle shaft. On the drivers, she twisted up pretty good. Looks like the R&P survived. I knew I was gambling with my trip and the trails I was on, I get it.

I hate being broke and not having a plan. So 1 tons it is. The weight of the vehicle, 40’s and playing in the rocks, bad combo for the D44’s and the JT.

for those on D44’s I’d look at getting a set of rear axle shafts as spares. Stocks appear to be on B/O and other companies are weeks out. I was able to get a revolution pass side rear at the vendor show, by luck. It was there display axle. I also ordered a set of Yukons as those appear to be available, hoping to get them next day. So I could go play one more time. The drivers side revolution is also in route. So I’ll have the yukon’s as spares.

I’ll be honest, I’m a bit concerned about the upgraded shafts in the rear eating the R&P, so will see. Upgrading components leads to the next weaker link in the chain. Maybe should have stayed with 1310 drive shafts. Thats easier to fix than where I’m at now.

have the rubicon planned for September and not sure I’ll have the tons in yet. So I’m sure we will push the D44’s one more time!

I am building my 1 tons, pulled a set of 2010 super duty axles. Starting the prep this weekend, at least that’s the plan. It’s way cheaper than crate axles!
My thought for keeping my driveshafts stock for as long as possible was to keep them, hopefully, the weak link. The flaw in my logic is I don't carry spare driveshafts but at least driveshaft shops are fairly common. I do carry my stock axle shafts as spares.

But my fear is that my pinion is now my weak link, and not my driveshafts. Which you haven't exactly quelled

::edit::
I missed that the pinion you toasted was 5.38 gearing... that must have been a tiny pinion. And super aggressive gearing with the diesel. So maybe not as bad
 

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Lotta guys I know running 42s only truss the front axle. Rear is pretty sturdy as is, most of the weight is up front, just get nice suspension and the rear would be fine. I haven't trussed my front yet, will after moving to 42", but I run 7 and 8 level Moab trails with 37 MTs and completely stock axles. Not broken anything yet and go twice a month wheeling. 4.56 gears.
 

jim.rishel

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Lotta guys I know running 42s only truss the front axle. Rear is pretty sturdy as is, most of the weight is up front, just get nice suspension and the rear would be fine. I haven't trussed my front yet, will after moving to 42", but I run 7 and 8 level Moab trails with 37 MTs and completely stock axles. Not broken anything yet and go twice a month wheeling. 4.56 gears.
Man 42’s on D44’s….man I’d break those hitting the speed bumps at the mall! If I sneezed wrong I’d throw an axle shaft. That’s living on borrowed time IMO. After seeing the splines twisted up, yeah, stay on 37’s and wheel it!
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