CLSegraves1

I'm in the midst of my WJ knuckle swap and overall it's going quite well. However, I'd appreciate some insight into setting up the drag link angle/pitman arm location relative to the knuckle connection.

As it currently sits at ride height (~4.5" lift), the pitman arm connection point is 4.5" higher and 3" forward of the knuckle connection point (axle is pretty close to stock location fore/aft). While this setup makes for decent drag link angle at ride height, when I drop the axle to full swing (between 6" and 8" of drop) the angle of the drag link gets pretty steep. Because of my springs (and bump stops), I don't get much compression (~ 2").

What I was thinking of doing is getting a 2" drop pitman arm and moving the axle forward (1" to 2" depending on how everything works out). This would put the drag link very close to parallel to the axle in all planes and as long as the pitman arm connection point is always equal to or above the knuckle connection point, then I should never bind on compression but would have a much better drag link angle on drop.

Insight from those more experienced is appreciated.

oldguy52

I'm doing same and was hoping to post up finished today but fell behind due to spending 4 1/2 hours on lower ball joints. Hope to post up later this week with details.

I'm working same ride height and I'm not getting the same angle for the drag link with stock pitman arm. From knuckle to pitman I only rise .75 inch. Post up a pick.

CLSegraves1

Here's a shot of how it sits currently. As you can see, I'm already at a decent angle. When I go to full drop, the angle gets near the limit of the rod ends.

oldguy52

Just occurred to me that you're probably going with TREs under the knuckle. If so then that would explain your angle. You'll want to look at something like goferit inserts (link below). You want to flip your tie rod and drag link on top. If you don't have welding available to you then you'll need to look into a reamer. Under the knuckle will leave you with bad angles.

http://www.goferitoffroad.com/products.htm

oldguy52

Sorry. looks like we were typing at the same time. I'm at a loss.

CLSegraves1

You must have posted just as I made my post.

I'm using 7/8" rod ends that are bushed to take a 3/4" bolt and the knuckle is drilled straight through. I have everything on the top.

CLSegraves1

Could I have the "wrong" pitman arm (not a cherokee pitman arm)? Can you snap a picture of your pitman arm so I could compare it's drop to mine?

oldguy52

Looks right to me but I'll post when I get home. You sure about your ride height? I measured mine from top of axle to the underside of the frame. I'm at 11.25 inches. Stock is 6.75 inch. You look like you've got more.

CLSegraves1

So "dohhh" moment. I didn't think about the fact that I had the rear of the body up on jack stands and that was throwing off the ride height of the front (measured it and the front was up equivalent to a 7" lift). Got the rear back on tires (and front down to my 4.5" lift height) and sure enough it's right about where I want everything (pitman arm connection is about 2" higher than the knuckle connection).

Good lord this new front end has nearly 10" of drop! I'm going to need to dig up some longer travel shocks. The takeoff Rubicon shocks I was running only have 8" total travel so I need something with near 12" of travel.

oldguy52

Glad you figured it out. I found the same thing. The stock steering causes the control arms to bind before you get very far. With this setup it drops to the floor. I'm going with Bilstein 5100 for 5-6" lift and 11.47 " travel front 10.02 rear. Gotta set bumpstop correctly.

CLSegraves1

How are you doing your bumpstops? I was going to get some aluminum bar and cut pieced to sit on the axle (inside the spring).

oldguy52

Bought a pack of hockey pucks at Modells.

Drilled and tapped 3/8 in front spring bucket will put 2-3 like this



You could buy but I made this for the rear and will also drill/tap to add 1-2 pucks

CLSegraves1

Okay, resurrecting this "issue". So as I near the end, I have discovered that at full drop the rod ends on my drag link are binding (the axle is getting near 10" of drop below ride height). When this binding occurs, it's enough to actually deform the rod end bushings (not the rod end itself but the bushings that bush down the rod end diameter from 7/8" to 3/4") as it's taking the full weight of the axle. I'm inclined to add a 2" drop pitman arm which SHOULD prevent the drag link from binding at full drop (so the control arms will hit before the drag link binds). Any issue with doing this?

CLSegraves1

I also could use some advice on track bar vs drag link length. My drag link is 34.5".

Because I am using "factory type" coil springs (not coilovers), my track bar has to go "inside" the passenger's side spring. If I try to get a 34.5" track bar, the frame mount sticks WAY "outside" the driver's side frame rail. I've gone around and around, but it seems to longest reasonable track bar I can stuff into this thing will be 32" (best case... might be limited to 30" once all said and done). Assume I can only get a 30" track bar, is that going to cause significant bump steer on the street? I'm not worried about bump steer at full (10") drop as I'd be crawling at such speed, I just want to make sure that at 80 mph (highway speeds around here) I'm not going all over the road.

oldguy52

You might want to check out my conversion here

https://www.cherokeeforum.com/f67/wj-conversion-238205/