Bench Racing; TJ Crawler build

[Asbjorn]

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I like what I see!

 

[Greg]

Definitely just do SD axles. It’ll be cheaper, stronger and I’d wager not a whole lot heavier once you beef up the JK axles.

I’d also skip the ORI’s if it was me. Air shocks will do everything you want and are cheaper, lighter and easier to get your hands on.

Oh and just do 4D’s. They’re the new 37’s ?

My dos pesos

I totally understand where you're coming from on the ORI's, JK axles vs Super Duty's, 40's, etc. The issue I have with SD axles and 40's is that once I do all that, I don't know that the TDI is enough to push a rig around.... and then, I might as well swap the TDI for a GM 6.0, better ditch the D300 for an Atlas and now the budget for the trail rig has doubled! I was thinking that this TJ would be 'light' compared to something on Tons and 40's. IMO air shocks seem like a compromise all around, I think if I didn't do ORI's, I'd just run coilovers.

Sounds somewhat familiar. My thoughts (I might be a little biased )

My original plan was for 37s. I didn't need a bigger tire. One trip up helldorado changed that thought. But a 40 is much bigger to squeeze in and I had to raise my highlines so as not to limit my uptravel.

My original plan was also a 102-104" wheelbase. Seven, maybe 8 inches is all you can stretch in the rear without a comp cut. That would have been a 2-3 inch front stretch. For the effort of moving the steering box, it made more sense to move to a scout 2 or fj60 box that mounted outside the frame with a forward swinging pitman arm. At that point, 108" makes sense. Boatsides are awesome. And a lot of work.

JK axles have their merit, but you'll be cheaper to just put in a set of 05 plus SD axles. Every time I see JK (really any linked Jeep) axles for sale, I can't help but wonder if they are gold plated. $600-800 will get you a pair of SD axles. $800-1000 will get you just a rear JK axle from what I've seen. And with custom suspension, they wouldn't really be that much different for the amount of work required.

I haven't had any problems with my tank mounted behind the seat. Even with a top (that hasn't been on for a couple years). I would put the tank right behind the driver seat if you aren't doing a rear seat. Makes accessing your cooler and tools way easier and keeps the weight more central.

I'd do coilovers rather than struts or airshocks. Personal preference based on observation. And I really like my tuned coilovers. Saw a TJ last time I was in Moab with struts. He was touting not needing swaybars or bumpstops. That thing looked super unstable on the couple large climbs I watched him attempt. Much like a slinky. Maybe it needed tuning? If you aren't going to ever go fast, you really don't need bumps with coilovers either. And there are things you can do to the shocks that can make it so you don't use bumps and still have decent bottom out resistance.

I've never run krawlers, but did almost buy a set of blue label 39s when it took 6 months to get km3s. Also to note, my 39" km3s are about 38" with 25 psi in them. Much shorter than that with lower pressure.

All in all, I think my rig is about as close to a swiss army knife as you can get. It does a lot of things pretty well. It crawls well, can go decently fast in the rough stuff, drive down the highway at 70-80 mph and I can put a top on and crank the heater to stay warm in the winter. Defrost is magical. The hyrdoassist isn't my favorite, but I have some things I'm going to try this winter to try and improve it. May end up with a double ended ram among other things.

Yeah, sounds like a lighter, scaled down version of the TJ pictured above!

I've seen JK axles for around $300-400/ea, which seems pretty reasonable. I think with 37's and some beefy shafts, they'd do the job just fine. Obviously they wouldn't be as beefy as SD axles and you'd have to be more cautious, but I think they would work. I'd plan on sleeving the front, probably trussing both housings, etc. I could just run KM3's for a lighter tire, to help keep the axles alive.

I know we have talked about ORI's in the Willys Crawler thread and I ended up buying 14" Fox Remote Res coilovers for it. I like the idea of ORI's for their ease of packaging, not requiring additional bump stops, limiting straps and the claimed stability. The one's I've seen in action made for an incredibly stable rig, but I'm sure the wrong nitrogen pressures or tuning can make they work funny. But you're right, coilovers would offer much better tuning options and be cheaper than ORI's.

I think something like this wouldn't need a full on comp cut, if I could push the front axle forward 2" and the rear back 7-8" and still have a normal looking wheel well, gain a decent wheelbase and not make it look too cut up. I'd be happy with that.

I would love to start a fresh dedicated crawler project out of a TJ or YJ. Many of your initial thoughts are similar to mine.

I have a JKR44 in the front of my LJ. It holds up to 40's. I have it trussed, sleeved, gussets, RCV's and Cryo treated the 5.38 gears with an Ox air locker. It took a lot of $ to build it up like that, but I don't baby it. Truthfully, the only way I would recommend JK axles is if you get a great deal with the lockers, knuckles and brakes included. All that crap adds up if it wasn't included in the JK housing. Otherwise you'll spend the same amount of $ and have a tougher set of axles out of a SD. I do have a friend selling a set of JLR 220 axles which are awesome! He ended up with 2 sets, so one is up for grabs for $4k (although his set does not include brake calipers).

Dave has me intrigued with what he's saying about the steering box and front end stretch.

I love ORI struts if they are tuned right. If they aren't, they can crash your jeep in a hurry. I wheel with a lot of guys at SH that swear by ORI struts, and when I'm with them, I swear by them. But I have had strangers in some of my groups that end up super tippy. On the other hand, I am regularly on the trail with guys with coilovers that the front end unloads all the time. I'd rather have stock short arms than have the front end loose traction the way most coil over rigs do on a super steep climb. But then again, that probably has a lot to do with tuning and proper springs too. I am no expert on struts and coilovers, I just know either way will take you a lot of time, trial and error to get them dialed in. I'm not yet convinced to ditch my shocks and coils.

Good insight, makes sense about buying a complete JK axle to build. I was pretty interested in your JK axle build, sounds like it's been working well for you.

I hear what you're saying about the ORI's, I haven't seen a set that was unstable, but also don't hang out with the hardcore wheelin' crowd these days. My old TJ was stupid stable and it was sitting on TJ coil springs and standard Tera 9550 shocks.

Wish I were better about build threads. My info may not be helpful anyway, since mine is based on a YJ. However, regarding the steering box relocation, I couldn't find much info so I just did it. I had already stretched mine 2" in the front when I was on leaf springs. Steering box in factory location. As I have been converting to links, I decided to stretch it another 2" and this time had to move the box. I cut the factory tube crossmember out and replaced with 2x4 tube welded to the end of the frame horns. I then plated the frame horns with 3/16", slid the box mount forward, marked, drilled, sleeved and welded. I had to notch the bottom corner of the grill for the lines to run to the box. There was some thinking and researching involved in getting all the right parts and clearance but really not too difficult on a YJ. I did look up the TNT stretch kit (after reading this thread) and it seems to be what I did - in kit form. However, it has the added benefit of rolling the box up and out of the way. I will just build a steering box skid plate. Anyway, here is a picture.

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Looks awesome Jason!I can't want to see how it changes your rig and what you think about the new setup. Yeah, a build thread would be nice...

 

[RockChucker]

I think something like this wouldn't need a full on comp cut, if I could push the front axle forward 2" and the rear back 7-8" and still have a normal looking wheel well, gain a decent wheelbase and not make it look too cut up. I'd be happy with that.

Mine is stretched 7" front and rear (roughly). No comp cut for me.....not a fan of the look. I was thinking you were using Ben and Kami's TJ for reference....or Spidey's YJ

 

[Greg]

Mine is stretched 7" front and rear (roughly). No comp cut for me.....not a fan of the look. I was thinking you were using Ben and Kami's TJ for reference....or Spidey's YJ

I do love your TJ, no question there!

I hear you on the full comp cut, it looked OK on my old TJ since it was so low and the 40's filled up almost all of the comp cut. But if I were to do at again, I wouldn't do the same thing.

 

[Greg]

I should reach out to Clayton that bought my old TJ and see if he wants to sell... last I heard, the engine/trans/t-case were pulled and it was tore down for upgrades.

 

[mbryson]

I should reach out to Clayton that bought my old TJ and see if he wants to sell... last I heard, the engine/trans/t-case were pulled and it was tore down for upgrades.

I saw it on PBB For Sale a few months ago

 

[Greg]

I saw it on PBB For Sale a few months ago

Yeah, I found his ad from some time ago... seemed priced way high, considering what had been removed from it.

 

[mbryson]

Yeah, I found his ad from some time ago... seemed priced way high, considering what had been removed from it.

That was my thought exactly

 

[RockChucker]

I do love your TJ, no question there!

I hear you on the full comp cut, it looked OK on my old TJ since it was so low and the 40's filled up almost all of the comp cut. But if I were to do at again, I wouldn't do the same thing.

LOL. I'd be lying if I said your TJ didn't play a role in what I wanted my Jeep to be.

Last I saw your old TJ, it was super cut up....*pause for searching*

Yup. Found it. https://www.pirate4x4.com/forum/vehicles-trailers-sale/2124186-hunts-rme-tj-builder.html

I think he wants way to much for a shell of a rig that needs a lot of work to finish.

 

[Gravy]

I think it climbs better with the rear stretched. Me and Benjy had the same wheelbase (105.5") and mine was more rear and his was more front. And the weight over the front axle helped.

 

[Hickey]

He hasn't updated that price in 2 years.

 

[Greg]

So, I have been watching this years Ultimate Adventure vids and it got me thinking about an all around TJ Crawler that was capable of roadtrips and serious adventure. Also something that could run the harder Moab trails and other challenging UT/CO trails, where my other Jeeps won't be going.

What a TJ is lacking is wheelbase and storage, so to fix that I'd want to build a TJ truck. Shorten a TJ tub, lengthen the frame and build a 5-6' flatbed. Obviously the sheetmetal work would be a huge challenge, as well as making a hard top work. Lengthening the frame wouldn't be too hard, IMO.... use one of the available TJ Back Half kits, like the one from Artec and build a new longer frame with 2" x 3" x .120 rectangular tube.

Far as the drivetrain, I think I'd still want a VW TDI with some mods, shoot for 300 ft/lbs of torque. I'd mate that to a AX15 and either 231 or flipped Dana 300. Possibly a 231 Crawl box, for a couple different low range options? I still think JK axles with upgraded shafts & joints and 37's would be enough, but I do think I'd spend the cash on a JK Tera 44 axle housing. Probably keep it on coil springs for simplicity, Falcon shocks, 37" BFG KM3's and possibly a backup set of 37" Krawlers for the rougher trails. I'd plan on keeping the steering box and running hydro assist.

With the longer frame and bed, try to find a factory 20 gallon tank that would work for more range. I'm sure there are plenty of options out there.

I think I'd try build the tub and hard top so that it was almost an extended cab, just a little more room behind the seats for storage, able to recline a little, etc. Shoot for around 110" whelbase, longarms for a great ride and plenty of wheel travel. High line fenders/hood, so you had a minimal amount of lift but still plenty of room for big tires.

There are options out there for a TJ halfcab hard top, from GR8 Tops... but starting at $2K and meant to work with a stock tub (bulkhead), I think I'd rather tackle the shortening job myself.

Anyway... that's the current thinking.

 

[LJTim]

I like this idea. I personally don't think I'd run a hard top. I would probably just do a bikini most the time, with some removable wind-jammer parts for the back, and soft door surrounds.

 

[jedi]

What’s your opinion on the 231 crawl box Greg? What brand would you use?

 

[Greg]

What’s your opinion on the 231 crawl box Greg? What brand would you use?

It's hard for me to give an opinion, as I haven't actually ran one in a working vehicle.... I did buy a Box 4 Rocks from JB Custom Fab and a good NP231, got it all set up (had a friend aluminum weld the block off plate) and was going to run it between an AW4 and Dana 300. I ended up parting out the project and selling the 231 crawl box and Dana 300.

They do seem like a good idea, I've always liked dual t-cases since you have a variety of gearing options. I think if you have the wheelbase to run one, they're a good option.

 

[Gravy]

I've ran a 231/flipped 300 box4rocks combo for years. Upgraded the planetaries from a 231c .
The 2.61 with 5.38s spins 40s great in the sand.
And double low 2.61 x 2.72 works so well in the rocks. Maybe JB Fab reverse cable shifters. I left the rear 300 output stock and used 1310 joints as the weak point instead of popping the case.