Long Travel Grand Cherokee ZJ Build

Instead of looking at all of GL4X4 members rigs I figured I would post up my own build thread for my Jeep Grand Cherokee Laredo ZJ. I'm a 19 year old kid who is going to school to become a Mechanical Engineer and have worked in machine shops and fab shops for a couple years now. I went to tech center the senior year of highschool and learned some pretty cool stuff such as how to run a CNC mill and lathe, manual mill and lathe, surface grinder, etc. Kind of taught myself to weld and do some other metal working things.
I started off by buying a 1998 V8 model ZJ for $1100 that came with some exhaust stuff and two sets of extra tires. Stole the motor, transmission, tcase, doors, axles, steering box, and some other miscellaneous parts. I sold some other things like interior panels, seats, seatbelts etc. A local GL4x4 member came and picked up what was left of the jeep, took what he needed from it, then scrapped it. I ended up a couple hundred bucks in the green from that hole deal after selling tires and such.

That leads to the second jeep I bought off craigslist. A 1998 (same year) Grand Cherokee ZJ V6 model for $400. Craigslist add and the gal I bought it from said that it had a blown head gasket and when I went to go check it out there was two big holes and a couple cracks in the block. I didn't care seeing as I had the drive-line from the other jeep so this deal was perfect. This body / sub-frame was in much better condition and was cheap!

Started the engine swap last winter and finished it in a fairly quick manner. Everything bolted right in besides the passenger side (I believe) motor mount. I had problems getting in running for a week or so and asked many different people and places if they had any ideas and ended up plugging the old V6 computer in. It fired right up but ran like shit so I ordered a new computer and it purred like a kitten for a couple months. I drove it for the rest of the winter, found a good deal on "lift kit" which was arms, coils, and pan-hard bars. Drove the jeep like that for a week or so and realized that just wasn't going to cut it! Which leads the story to where I'm at right now...

Bought a Dana 44 and Ford 9 Inch for $200 and just freshened them up a bit (New balljoints, U-joints, front rotors and calipers, pinion seals, etc.). I built a backbone truss the Ford 9 Inch and did a disk brake conversion on the it with RuffStuff brackets, Rotors are 1978 Ford F150, and calipers, hoses, and pads are 1976 Chevy K5 Blazer. A big thanks to John D for the help with disc brake conversion input!

Seeing as it will be a long travel toy and I've got a place up at Silver Lake, my buddy told me of a sweet deal for some General Grabbers, and I hopped on it. I believe they were $500 for the four 33 X 12.50 X 15's with 200 street miles on them. Bought some steel D-window rims from another member for $60. Plan to beadlock them at some point so I can air down and still whip the back end out and jump in the dunes without rolling a bead in the sand.

Enough background lets get to the pictures:

First ZJ that ended up getting scrapped


Second ZJ after motor swap and lift


Some of the brake and axle parts


The Ford 9 Inch with the homemade backbone truss (Will also get a truss on the top for the wishbone link mount)


Just the axle and tires setting underneath the jeep to get an idea of width and ride height


Fingered crossed I can get this much bump out of it!

Got quite a bit of things done this weekend!
I knew that I wanted to extend the radius arms from the beginning - after putting tires on and turning to full lock I realized that they had to be clearanced for tires which means more work!
My plan initially was to bend them... but after breaking a buddies bender and trying some other ideas I gave up and cut and mitered them.


After torching the arms and replacing with 2 inch O.D. .25 wall seamless tubing


The joint from stock arm to tube


Another picture of the joint. I milled the tubes at 10 degrees.


The arms after tacking them together


Hopefully enough room for up to 37" tires


Mocked up a template for an idea of link mounts


From cardboard to computer!


To computer to CNC!


The man behind the madness! Username is Mitchmiller on GL4x4.

Big thanks to Chad (K5 Yota) and Mitch (Mitchmiller) for the help this weekend!

Plans are suspension wise~

For the front:
Dana 44 with custom radius arms and panhard bar. coilovers going to radius arms just behind axle ( maybe 4" behind axle" )

Rear:
3 link wishbone with swing arms coilovers attached about 16" forward from the rear axle

Anyone have big bind issues with travel / flex running a radius arm front similar to the cast wedges that I have?

Thanks for the input guys

also, I copied and pasted this from my other build thread from GL4x4 as I am from Michigan
http://www.greatlakes4x4.com/showthread.php?p=3678273#post3678273

Cool build! I can't imagine an issue with bind, all the old bronco's ran this style suspension and they did well. But what do I know I've never played with it. Good luck! Can't wait to see the progress!

un sluged butt welded control arms are a very bad idea

ROBZ95Xj said:

un sluged butt welded control arms are a very bad idea

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i was thinking the same thing, and wondering why the miter cuts and rewelds instead of just putting a couple bends in it? the way you've set it up OP is almost guaranteed to fail at the weld. no matter how good your welds are, that area is now a heat effected zone and will be weaker than the surrounding material.

GrimmJeeper said:

i was thinking the same thing, and wondering why the miter cuts and rewelds instead of just putting a couple bends in it? the way you've set it up OP is almost guaranteed to fail at the weld. no matter how good your welds are, that area is now a heat effected zone and will be weaker than the surrounding material.

Click to expand...

X2

GrimmJeeper said:

i was thinking the same thing, and wondering why the miter cuts and rewelds instead of just putting a couple bends in it? the way you've set it up OP is almost guaranteed to fail at the weld. no matter how good your welds are, that area is now a heat effected zone and will be weaker than the surrounding material.

Click to expand...

I tried using a couple different benders and broke one, and the other one just flat out didn't have the force / power needed to bend the tube. Its 2 inch O.D. .250 wall seamless - I don't have the resources to bend it. I plan on plating the sides from front to back then boxing them in on the top and bottom. When I am done with that process I'm 99% sure I wont break them... I think :rof:

I have some good updates from this weekend! Big thanks to Chad (K5 Yota) for his help! Stayed up until 4 Saturday night and got some good stuff done!


There is a nasty pinch seam on the inside of the unibody near the transfer case crossover - which is right where the link plates had to go. Cut the seam with a 4.5 grinder with a cut off wheel then welded and ground the excess weld down so the plate could set flat against the frame.


Went through a coupla theese bad boys
So I was anal and measured (and got 2nd and 3rd opinions) pry 10 times to make sure both my link mounts were both in the same position on each side. I think they're within a sixteenth but hey whatever it will all work out... I'm not building a spaceship.... just an airplane :teehee:


This may be ride height - not sure yet - might be a bit lower in the end. This set up would give me ~8 uptravel and ~8 down (depends on the length of the coilover). Love how the links are next to level!!




In those pics you can see that the link hits the subframe before full bump... may french the subframe who knows... That's a pretty critical part of the unibody but if I do it right it should be alright.


A good pic to show full bump - or close to it

I have a long arm zj with the 9 in the back and the 44 sitting in the garage waiting to go in. you are doing a dam good job on that. jealous of the machine shop hook up. Looks GOOD.

Moparman - Thanks for the nice words.... and as far as those axles waiting in your garage... life is short and your not gettin any younger :rof:

looks good, but i dont know about those radius arms, ive seen major issues with them in the past, especially when modified.

Vanimal said:

looks good, but i dont know about those radius arms, ive seen major issues with them in the past, especially when modified.

Click to expand...

Could you expand on these issues?

RossDickman said:

Could you expand on these issues?

Click to expand...

They fail.

they didn't articulate whatsoever, and they bound up so much when they TRIED to articulate that they both cracked in half on an intermediate trail, and the axle fell out.

Vanimal said:

they didn't articulate whatsoever, and they bound up so much when they TRIED to articulate that they both cracked in half on an intermediate trail, and the axle fell out.

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intresting about the not articulating whatsoever so far ive heard that from ouple people but my set up is the raidus ends but mine went further into the dom tube and mine does flex decent. my shocks are limiting the front right now.
no bumpstops or shackle relocator in the back for this picture. on oem front spring front still had aways to go.


op I would be worried about the kink you welded into the arm and the actual ford radius arm you have left. but Im not a pro like the work so far keep it up. maybe frame stiffeners also

Right now the plan is the gusset / strengthen them so they will not break. If it does, I will start over and buy a dana 44 with welded wedges.... or independant atriot:

stang65 said:

intresting about the not articulating whatsoever so far ive heard that from ouple people but my set up is the raidus ends but mine went further into the dom tube and mine does flex decent. my shocks are limiting the front right now.
no bumpstops or shackle relocator in the back for this picture. on oem front spring front still had aways to go.

op I would be worried about the kink you welded into the arm and the actual ford radius arm you have left. but Im not a pro like the work so far keep it up. maybe frame stiffeners also

Click to expand...

The ones ive seen were set up with heims on the body end, and they definitely did bind up. The jeep in that pic doesnt appear to be flexing all that much in the front, the back seems to be doing most of the work. The issue is at the axle end, not much you can do about that.

Vanimal said:

The ones ive seen were set up with heims on the body end, and they definitely did bind up. The jeep in that pic doesnt appear to be flexing all that much in the front, the back seems to be doing most of the work. The issue is at the axle end, not much you can do about that.

Click to expand...

In that picture the rear is limiting me. the rear has no bumpstops and is rubbing on the fender while starting to pick up on the inside this is a older pic so the rear was stoping me from going further now im a .5" with shackle relocators and working on bumpstops.better shot of rear issues
I said before that it flexs decent. never said it was going to flex as well as something with a joint on the axle side but for the cost it does well. I will endever to get a picture of it with the new rear setup and it maxing the front out.

Been a while since I have updated the thread.
Got some good work done as I am on summer and haven't started working just yet.

To start off, I was sick of the Hi-Lo being a pavement princess so I added some rubber so I could drive in the grass... mostly on Tuesdays and such.


Then I put the ZJ on a diet and cut some of the fat off of er


After the chop


And the left over parts


Welded the bottom frame plates fully on the outside and cleaned up the sides for the new plates for it


Then for some reason the ZJ wanted to have a TJ shorty bumper so I let her (what was left after the cutting)


And the plates I made for the outside of the Unibody. They will go from the lower control arm mounts and tie in with them and span all the way to the front where they will be integrated with a bumper


I have a transfer case crossmember mocked and tacked up, I will take pics tomorrow or so.
I went up to Silver lake this weekend and there must have been a prerunner forum meet because there was 20 or so rangers with TTB/coilovers/bypasses/bumps/etc. Got some good ideas and some nice motivation

Thats all I have for now!