How much is too much side to side movement of axle during 3 link suspension axle travel?

[Choo Magoo]

My axle moves off center about 2.5” in total with 12” of total suspension travel. My panhard is 37” long and drag link is 36” long and they are within 2 degrees of each other at ride height. Anybody know an ideal number for how much the axle should move side to side during travel?

 

[Mike Shull]

Others may have a different opinion but I think that you are okay depending on your driving style. You might experience a slight jolt to one direction if speed and desert racing describes your style. This isn’t my thing so I can’t speak to whether this setup is good for that use. @EWheeler?. Rock crawling and general purpose driving should hardly be noticeable with that sort of movement. Based on the amount of shock shaft that is showing, I imagine that the picture above is fully extended and your drag link and panhard are less than 6* at ride height, which seems good.

Is there a problem that you are trying to diagnose?

 

[gnob]

how flat is the panhard at ride height ?

 

[Choo Magoo]

Others may have a different opinion but I think that you are okay depending on your driving style. You might experience a slight jolt to one direction if speed and desert racing describes your style. This isn’t my thing so I can’t speak to whether this setup is good for that use. @EWheeler?. Rock crawling and general purpose driving should hardly be noticeable with that sort of movement. Based on the amount of shock shaft that is showing, I imagine that the picture above is fully extended and your drag link and panhard are less than 6* at ride height, which seems good.

Is there a problem that you are trying to diagnose?

The only problem is that at full bump both of my coil overs sit 87 degrees, like this /\. But when I go from full bump to full extension the passenger shock moves past 90 by about 4 degrees due to the change in axle center.

My understanding is that the coils should be as close to 90 at full bump (I don’t know the reason for this it’s just what the internet says). So should I just set the shocks at say 83 degrees at full bump that way the passenger shocks doesn’t move past 90 at full extension?

My driving style is closer to rock crawling than it is high speed desert, but I am trying to build a well rounded vehicle that hopefully can do everything good but nothing great.

 

[Choo Magoo]

how flat is the panhard at ride height ?

The panhard sits at 3 degrees at ride height and is 37” long.

 

[Mike Shull]

The only problem is that at full bump both of my coil overs sit 87 degrees, like this /\. But when I go from full bump to full extension the passenger shock moves past 90 by about 4 degrees due to the change in axle center.

My understanding is that the coils should be as close to 90 at full bump (I don’t know the reason for this it’s just what the internet says). So should I just set the shocks at say 83 degrees at full bump that way the passenger shocks doesn’t move past 90 at full extension?

My driving style is closer to rock crawling than it is high speed desert, but I am trying to build a well rounded vehicle that hopefully can do everything good but nothing great.

I would not be concerned with the angle of your shock as long as they don’t hit the frame when you are fully articulated (one side up and the other side down). I would pay close attention especially to the right side since it may pivot more to the left as it travels down.

 

[Firemedic831]

That looks like that Pass side is going to hit the frame when you put the coil spring on .

 

[Firemedic831]

Also maybe its just me but it does not look like the shock towers are at the same angle ? plus you have something funky going on as a extension on the towers ? What is this anyways ? Did you build the frame ?

 

[Choo Magoo]

That looks like that Pass side is going to hit the frame when you put the coil spring on .

That’s my bad, I should have taken better pictures. The coils clear the frame and the tire no problem and the shocks towers are the same angle. I needed to extend the towers up to fit the 14” shocks. The ones I had were only meant for 12” shocks so I just made some extension plates.

 

[Choo Magoo]

Also maybe it’s just me but it does not look like the shock towers are at the same angle ? plus you have something funky going on as a extension on the towers ? What is this anyways ? Did you build the frame ?

It’s an 80 series with a 5.9 Cummins and f550 axles I’m swapping under it. The frame is stock 80 for the first 30” then it’s custom to the rear. It’s a chopped 80 with 20” extended wheelbase so I needed longer frame rails.

 

[Mike Shull]

I’m thinking that we are going to need more pictures of this for research purposes.

 

[Choo Magoo]

I’m thinking that we are going to need more pictures of this for research purposes.

I’m about two months away from getting it totally finished then I’ll post a brief write up of the build. Here’s a teaser from a few months ago though