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It seems that running a panhard is commonplace around here even when running leafs. I was getting ready to purchase the RuffStuff kit when I saw this post by Dan: http://www.ttora.com/forum/showthread.php?p=2272531#post2272531

Reading the following thread appears to confirm the fact that leafs and panhards work against each other due to the amount of structural support you must give the frame to run one.

http://www.ttora.com/forum/showthread.php?t=114425&highlight=panhard

On the initial test drive after completing my SAS, I noticed a lack of response in steering, some wandering and some bump steer. All of these would be corrected with a panhard, but what are some alternatives to correcting them?

I believe the play to be in the leaf spring and/or shackle bushings. The bushings appear to be poly, but did not come with metal sleeves for the bolts. Would the sleeves help with bushing twist?
 

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It seems that running a panhard is commonplace around here even when running leafs. I was getting ready to purchase the RuffStuff kit when I saw this post by Dan: http://www.ttora.com/forum/showthread.php?p=2272531#post2272531

Reading the following thread appears to confirm the fact that leafs and panhards work against each other due to the amount of structural support you must give the frame to run one.

http://www.ttora.com/forum/showthread.php?t=114425&highlight=panhard

On the initial test drive after completing my SAS, I noticed a lack of response in steering, some wandering and some bump steer. All of these would be corrected with a panhard, but what are some alternatives to correcting them?

I believe the play to be in the leaf spring and/or shackle bushings. The bushings appear to be poly, but did not come with metal sleeves for the bolts. Would the sleeves help with bushing twist?
There are a few things you could do to minimize some of the flex causing the issue on the shackle end. Probably making the shackles one piece would do the most to fix this; stiffer bushings would help some as well. I run a panhard bar on my Leaf-SAS Tacoma. It does induce a LOT of stress in the mounts. However, my truck tracks beautifully on road, and I no longer have uncontrolled bump-steer on trails. My axle housing is from an '88 Grand Wagoneer--that had a factory panhard bar on the OE leaf sprung axle. My 2000 F350 with Leaf springs has a factory panhard bar. Jeep YJ's come factory with leaf/panhard.

Before I installed a panhard bar, I tried keeping the bushings perfect and the on-road manners weren't terrible, but on the trail, I'd hit things on the side of the trail that weren't even on my path because of the bump steer (and my leafs are relatively flat ie:shouldn't be much bump-steer) I'd look out the window and see the tire full-lock to the left and my steering wheel hadn't moved (PS droop/DS compression).

My original install of a panhard bar on my truck ripped the bracket on the frame (ripping the frame in the process), and severely fatigued the 1/4" aftermarket bracket on the axle housing. I'll say it again, the panhard bar induces a LOT of stress; more so if you have fairly arched leaf springs. I've reinforced the frame (plated on all sides) and the axle bracket and I haven't had an issue with the panhard in 4 years of trail use (I replaced the heim joints once to get rid of squeaky sound). For me, it came down to this: Maintaining Stiffer bushings and shackles that resist the flex so the steering will be somewhat more precise while wearing out bushings a a quick rate; and having less suspension flex due to stiffer bushings/shackles ...OR Panhard bar that keeps steering precise all the time and sloppy bushings/shackles that allow plenty of flex while not affecting anything else. Just like with a link suspension, the panhard bar needs to mimic the length and path of the drag link to completely eliminate bump steer. My panhard bar is a little shorter and not perfectly in-plane with the drag link, but I have very little, and more importantly VERY predictable bump-steer. I don't have a sway bar and the truck leans a lot on curvy roads; it used to be a hand-full to keep the truck in it's lane, now I let people drive it and they aren't even aware there's something different about the truck's handling.

Pic (for no real good relevant reason); You can see part of the large triangular gusset for the panhard bar on top of the passenger side of the axle housing. The frame bracket is tucked up outside the frame behind the pitman arm. (sorry for large pic)

 

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Awesome info...Thanks. I may try adding a cross bar to the shackles to see if that helps before going to a panhard. I wish I had bought the panhard before so I could have built around it. It looks like the shock hoop and or shock may be in the way on the outside of the driver's frame rail and the motor mount on the inside.
 

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I opted NOT to do the panhard bar..

I shortened my front shackles to 3.5" and it drives like a dream.

The spring eye will contact the frame under extreme flexing..(no biggie)

You can feel the spring rate ramp up quicker, and it keeps it from bottoming out as much.
 

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I run a panhard, but ONLY on the street. On the street there is not enough stress to worry about because the panhard is only forcing over the leafs 1/2" or so.

On the trail though, there is a TON of stresses added to the frame and leafs. When droops, the panhard is forcing the leafs over at least a good 2".

I pull a cotter pin, and slide the pin out that attaches the heim to the axle. I then slide it into a welded pin on the frame and slide a cotter pin on that to keep it up and out of the way.

To reattach, sometimes I have to have someone turn the truck left or right slowly to line the panhard back up with the hole. If nobody is around, or I forget, it's still fully driveable, there's just a little bit more slop in the steering.

You go from 1/4 turn on the steering wheel before anything happens, to instant response when you turn the wheel. Really makes it like driving IFS again.

The nice thing is my leafs/bushings/shackles are still flexy enough to really flex out on the trail.
 

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I'm also considering running a pan hard. Probably I will end up getting the kit from rough stuff. I'm using a FJ60 axle so I will be able to put the link bracket on top of the diff. From what I'm reading here it sounds like the pan hard is good for street driving and just disconnect it on the trail? I will be using leafs and 5" shackles with 35"s. Thanks


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After 2 years, I'm looking at adding a panhard to my setup. Could you guys post a couple pictures of yours, and maybe lengths of your draglink and panhard? Im trying to decide where to put this thing. I'm planning on using the kit from ruff stuff. Just trying to get ideas.
 

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I'm linked so not useful. The longer the better and more parallel to the drag link the better. Flatter is better too at ride height to limit side to side movement. You probably already knew all that if you've been thinking about this for a few years, but just in case ya didn't.

Running FJ80 axles under my Tacoma with a IFS steering box, my lengths are both in the 41" range, eye to eye.
 

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Thanks for the reply. I have read a bunch. I just wanted to get some ideas for what's been done. With leafs, there isn't really enough to room to get it as long as my drag link, at least I can't find the room, damn springs are in the way.
 

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Thanks for the reply. I have read a bunch. I just wanted to get some ideas for what's been done. With leafs, there isn't really enough to room to get it as long as my drag link, at least I can't find the room, damn springs are in the way.

Yeah I'll snap some pics when I drive my truck tomorrow.

I went from the outside of the frame, to the top uboltplate on the pass side. Not ideal, but the ubolts have never loosened up.

I did bust a leaf on that pass side, but that was also 80k miles of highway and trail use.


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I thought about that. I was kinda hoping to not have to completely rework my bump stops, but this way would allow me the most length. I almost have room outside the leafs, but not quite.

Mr. Tacomi: I remebered reading about your dual case install (I copied your shifter and crossmember). There is a good picture with your panhard in the back ground. Being mounted on the axle, inside the leafs, any though on the length? This would be my ideal location as far as ease on install goes. I'm thinking of offsetting it to the front of the axle. Of course it wouldnt be as long as if I mounted it on the u bolt plate. I'm planning on disconnecting it while on the trail, so maybe a little short isn't the end of the world?
 

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I think if you go too short, you increase bump steer since the axle isn't following the same arc as the drag link. The longer (or closer in length) to the drag link, the better.

Yeah, the bump stop placementon that side is funky, but it works..


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After reading this thread many times, I realized "Panhard opinions?", in the original post, is a link to another thread! That thread has a bunch of useful info, and pictures. I guess it never came up in my searches.
 
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