Jeep Enthusiast Forums banner

XJ Flat Belly/ X member Build. Is it possible? Let's see....

49709 Views 76 Replies 21 Participants Last post by  DeftwillP
Well, thought I'd do a build on this separate from my XJ build. For those who don't know, my XJ is on about 3" of lift and 35's. I wheel my XJ in big pointy rocks that love to rip on anything they can on the bottom of my rig. I love the low stance of my heep and it works well, but it has it's drawbacks. EVERYTHING under my XJ has been taken into consideration because of it's low height. When you are this low, you rub and drag on rocks a lot. Is this a bad thing? Well, if you have the right armor and have clearanced everything that should be, then no. However, I have left one of the most important items untouched and it's way overdue for a replacement. This would obviously be my cross member. The factory X member is weak and hangs below the frame rails. At the same time, the bottom portion of the transfer case also hangs below the frame rails. This holds me up. Some how, I have yet to have exploded my transfer case. In the wheeling trips I have had this year, I have managed to turn the factory X member into an upside down U shape, which actually lifted my transfer case above the frame rails. Still, the cross member hangs too low. In this next pic, I was denied from getting to the top of this rock, even after repeatedly slamming into it trying to bounce and slide the cross member over the rock....



So, where does this leave me? It leaves me wanting a completely-flat -to-the-frame-rails-cross member, one that is strong, and wanting my transfer case completely out of the way. So first, out with the old....





To do this cross member, I got a clocking jig



and some 2x6 3/16 wall



So after doing some measuring, finding the center, and how much material should be shoved up between the frame rails, I came up with this....









Using the center point, I kinda (yes, kinda) figured where the trans mount should go. I drilled holes and got this....



And this is where I leave you hangin' til I get some more work done!
1 - 20 of 77 Posts

· Premium Member
Two ZJ niners
Joined
·
11,932 Posts
What are you gonna do with the exhaust? Run a more compact- sized cat and muffler? It's pretty damn tight fight to get a muffler and cat tucked into a flat belly without cutting the floorboards.. :mad: Flat belly, low stance and large tires is the way to go IMO so you're on the right track :)

I'm guessing you don't even need to notch the tranny x-member for front DS with the clocked TC? How are you going to mount this thing, weld in an extra support plate to the "ears" and add vertical mounts with crush sleeves through the unibody? Sure looks like a good starting point :thumbsup:
 

· Registered
Joined
·
4,372 Posts
Discussion Starter · #4 ·
Timo_90xj said:
What are you gonna do with the exhaust? Run a more compact- sized cat and muffler? It's pretty damn tight fight to get a muffler and cat tucked into a flat belly without cutting the floorboards.. :mad: Flat belly, low stance and large tires is the way to go IMO so you're on the right track :)

I'm guessing you don't even need to notch the tranny x-member for front DS with the clocked TC? How are you going to mount this thing, weld in an extra support plate to the "ears" and add vertical mounts with crush sleeves through the unibody? Sure looks like a good starting point :thumbsup:
The exhaust actually is going to work I think. My exhaust has already self clearanced itself into my floor board. If it is too tight, I'll massage the floor or notch the crossmember. As far as mounting, for the time being I'm going to use the stock mounting holes just to get it on there. As you can see, the metal sticks out long that the frame rails are. I'm going to fold that metal up around the frame to "hug" it and then run mounting points through the frame. I'm sure the bottom factory bolts won't last long!
 

· Banned
Joined
·
2,986 Posts
You should rent that jig out when you're done. 5 bucks to your paypal and mail it to the next guy.

I've seen a thread where a reamer just travels around from one person to the next for people going to 1T TRE.

I've thought about clocking my t-case if I decide to pull it for my SYE, but 45 bucks for a jig I could make for myself seems spendy.

I have an old stock x-member that looks close to yours.
 

· Premium Member
Two ZJ niners
Joined
·
11,932 Posts
As far as mounting, for the time being I'm going to use the stock mounting holes just to get it on there. As you can see, the metal sticks out long that the frame rails are. I'm going to fold that metal up around the frame to "hug" it and then run mounting points through the frame. I'm sure the bottom factory bolts won't last long!
Should work that way..

If I may suggest, you might want to use 10mm countersunk hex-head bolts (class 10.9 or 12.9 so they are hard stuff), then weld another 3/16 plate to the bottom of the "ears" and drill large enough holes where the mounting bolts go through - so large that the head just goes through the hole as well.

This way you will have countersunk bolts, and the additional 3/16" plate both gives you added strength on the key area, and also gives you just that much clearance over the bolt heads so they don't get smashed to rocks as easily. I did the x-member on my ZJ this way, and I've scraped the heck out of it on rocks and so far zero marks on the bolt heads :thumbsup:
 

· Registered
Joined
·
4,372 Posts
Discussion Starter · #9 ·
I like that : ) .. while your there... should put some long arms on : )
Thanks. No long arms on this XJ. I can make short arms work just as well. I'll also have more clearance and making what I'd want (mid arm 3 link) is way more work than I want to put into it right now.
Nice work! Can't wait to see how your plan turns out, I've got to do something for mine.
Thanks dude!

You should rent that jig out when you're done. 5 bucks to your paypal and mail it to the next guy.

I've seen a thread where a reamer just travels around from one person to the next for people going to 1T TRE.

I've thought about clocking my t-case if I decide to pull it for my SYE, but 45 bucks for a jig I could make for myself seems spendy.

I have an old stock x-member that looks close to yours.
Is it legal to be a jig pimp? :rofl:

Should work that way..

If I may suggest, you might want to use 10mm countersunk hex-head bolts (class 10.9 or 12.9 so they are hard stuff), then weld another 3/16 plate to the bottom of the "ears" and drill large enough holes where the mounting bolts go through - so large that the head just goes through the hole as well.

This way you will have countersunk bolts, and the additional 3/16" plate both gives you added strength on the key area, and also gives you just that much clearance over the bolt heads so they don't get smashed to rocks as easily. I did the x-member on my ZJ this way, and I've scraped the heck out of it on rocks and so far zero marks on the bolt heads :thumbsup:
That sounds like a great idea! The studs in the frame, do they just twist out? I didn't want to try it to find out I couldn't put another bolt in there.
 

· Registered
Joined
·
12,437 Posts
Is it legal to be a jig pimp? :rofl:
Don't let the man keep you down!

That sounds like a great idea! The studs in the frame, do they just twist out? I didn't want to try it to find out I couldn't put another bolt in there.
Yes the twist out, the double nut technique works very well.... wait, what? Also, if you look in front of the factory cross member mounts there is a sleeved hole on each side, you can tap that and use that for a 3rd bolt to hold the cross member on.
 

· Registered
Joined
·
4,372 Posts
Discussion Starter · #12 ·
I'm sure you've seen these type of things before, but it's an alternative to the 3/8s plate idea. Plate would probably be cheaper anyway.

https://www.ballisticfabrication.com/mobile/product.asp?itemid=1684
Actually, I have never seen those! Might actually order a few....

Yes the twist out, the double nut technique works very well.... wait, what? Also, if you look in front of the factory cross member mounts there is a sleeved hole on each side, you can tap that and use that for a 3rd bolt to hold the cross member on.
Thanks man. Good info. I'll replace those studs with new bolts.

I got a little more work done. I didn't get any pics but I will this week. I slotted holes for the factory mounting locations and all but got the X member completely under the XJ. I think I need to do a little more trimming on the middle boxed part.
 

· Premium Member
Two ZJ niners
Joined
·
11,932 Posts
Thanks. No long arms on this XJ. I can make short arms work just as well. I'll also have more clearance and making what I'd want (mid arm 3 link) is way more work than I want to put into it right now.
I've been thinking about the idea of fabbing high clearance axle brackets, that way the lower arms would basically be flat up to around 3" of lift or so.. With a little extended wheelbase and adjustable arms that should work ok.

There are a couple issues though; you'd need to rebuild the upper mounts as well, basically needing to fab a truss (possible fitment issues at full bump). Another problem is the added leverage because of the mounts being fairly far behind axle centerline. Then again, with OTK steering and flat arms the on- road handling should be great, and axle articulation + obstacle climbing abilities when wheeling really good as well.

3- link mid arms or long arms would be great, but they sure are a lot of work.. but so would be high clearance brackets :D
 

· Registered
Joined
·
4,372 Posts
Discussion Starter · #15 ·
I've been thinking about the idea of fabbing high clearance axle brackets, that way the lower arms would basically be flat up to around 3" of lift or so.. With a little extended wheelbase and adjustable arms that should work ok.

There are a couple issues though; you'd need to rebuild the upper mounts as well, basically needing to fab a truss (possible fitment issues at full bump). Another problem is the added leverage because of the mounts being fairly far behind axle centerline. Then again, with OTK steering and flat arms the on- road handling should be great, and axle articulation + obstacle climbing abilities when wheeling really good as well.

3- link mid arms or long arms would be great, but they sure are a lot of work.. but so would be high clearance brackets :D
I've thrown this idea around a good bit. I just can't justify putting that much work into a Dana 30!
 

· Premium Member
Two ZJ niners
Joined
·
11,932 Posts
Kinda thinking the same way :D Swap in a D44? ;)

I'd do that, if there weren't the stupid laws here in Finland that prevents me from deleting abs- brakes and running wider track axles..
 

· Registered
Joined
·
4,372 Posts
Discussion Starter · #17 ·
Kinda thinking the same way :D Swap in a D44? ;)

I'd do that, if there weren't the stupid laws here in Finland that prevents me from deleting abs- brakes and running wider track axles..
I'm so stuck on the fence on this.I'm a college student so I don't make all kinds of money. I keep telling myself to stay on 35's until I'm done with school. If I did a 44 swap, I'd then want a 9" or 60 and 37's, do a mid arm 3link, blah blah blah......... :laugh:
 
1 - 20 of 77 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top