Bouncer chassis shifting side to side.

bigredkacy · Mar 7, 2016

Alright. So I took it out for the first beating this weekend and I can't figure out why the chassis is shifting from side to side.

If you push the front drivers side towards the passenger it will move like 2 inches and the same the other way. This cause my bump stops to get caught under the lower brackets and ripping them out under heavy suspension flex.

All the jam nuts are tight, the links are straight, the 4 link has the proper angles.. I know a link does not need a pan hard bar but what's would cause this?

https://drive.google.com/file/d/0B0mD7kHIIBdkT3IwNEdGVkpZb28/view?usp=docslist_api

bad80cj · Mar 7, 2016

Dude we need way more than that to help you.

TacomaJD · Mar 7, 2016

You must not have installed the lug nuts.... :woot:

:smoke: ;D

Eddyj · Mar 7, 2016

What is the angle of the lower links in comparison to the upper links when looking straight down?

pholmann · Mar 7, 2016

Sounds like not enough triangulation.

al1tonyota · Mar 7, 2016

I've seen that kinda thing happen when the holes in the link tabs were drilled to big so the bolts could move causing slack side to side and twisting! If there isn't slack in anything then suspension geometry is all that is left!

bigredkacy · Mar 7, 2016

Sorry about the lack of info. I'll try to get some better numbers on the geometry and check the sizes of the hiem holes.

Figured I'd ask to see if any thoughts came to mind effort I run the numbers again.

al1tonyota · Mar 8, 2016

bigredkacy said:
Sorry about the lack of info. I'll try to get some better numbers on the geometry and check the sizes of the hiem holes.

Figured I'd ask to see if any thoughts came to mind effort I run the numbers again.

Ok after looking at your picture link. You have single triangulated four link because of the rock wells the axles shifting from side to side as the suspension cycles is very common with that setup! The easiest fix is to make wider landing pads for your bump stops!
Just FYI an 1/8" at the lower link heim will multiply depending on the length of the link.

TBItoy · Mar 8, 2016

al1tonyota said:
Ok after looking at your picture link. You have single triangulated four link because of the rock wells the axles shifting from side to side as the suspension cycles is very common with that setup! The easiest fix is to make wider landing pads for your bump stops!
Just FYI an 1/8" at the lower link heim will multiply depending on the length of the link.

Yep, what he said.

tri lowers with straight uppers make the axls that the axle pivots around pretty low, so the top of the axle moves around a lot, and the axle moves a lot during flex.

bigredkacy · Mar 8, 2016

Yeap it is a single triangulated 4 link. If it is common that puts me at ease.

I will make the lower perches/landing pads for the bump stops wider.

The link itself is 52" without the hiems.

Here is a good picture of what it was doing all weekend, pulling the bumpstop out of the can as it flexed and caught the lower landing pad.

Elliott · Mar 8, 2016

Change your upper on one side with triangulation, sounds wierd but works. My last one like this worked great with no drawbacks at all . And to make this more clear Bottom triangulated like normal, 1 straight upper ,1 triangulated

bigredkacy · Mar 8, 2016

Elliott said:
Change your upper on one side with triangulation, sounds wierd but works. My last one like this worked great with no drawbacks at all . And to make this more clear Bottom triangulated like normal, 1 straight upper ,1 triangulated

Do you have any pictures of how you did it with the rockwell??

Elliott · Mar 8, 2016

I probably due but it could take me a little bit to find them. basically I kept the same math as I usually would where the uppers were 25% shorter that the lowers, this is assuming they were being mounted double triangulated , then I figured where my mounts would be normally located, this gave me the mounting point for the straight bar and the measurements for cutting it because it will become several inches shorter than the other top bar.I know this sounds strange and everyone argued with me about this working when I built it but it has had the living **** beat out of it with no problems now and its growing on 4 years old now.

paradisepwoffrd · Mar 8, 2016

Re: Re: Bouncer chassis shifting side to side.

Elliott said:
I probably due but it could take me a little bit to find them. basically I kept the same math as I usually would where the uppers were 25% shorter that the lowers, this is assuming they were being mounted double triangulated , then I figured where my mounts would be normally located, this gave me the mounting point for the straight bar and the measurements for cutting it because it will become several inches shorter than the other top bar.I know this sounds strange and everyone argued with me about this working when I built it but it has had the living **** beat out of it with no problems now and its growing on 4 years old now.

For crawling this might have little to no effects. Might wear joints more as the links are likely binding some during travel.

Toddy · Mar 8, 2016

Those tall ass mounts will move around a lot more then a shorter mount too. Prob gonna take a wide mount to be able to fix problem. If you can deal with the sway build big pads and wheel it.

Elliott · Mar 8, 2016

Links didn't bind at all, it was picked up with fork lifts and checked as soon as it was a roller, I would personally not build a rockwells rig any other way, it just made everything work, even able to use a 1 piece front driveshaft with no interference.

al1tonyota · Mar 8, 2016

Go look at 90% of the Rockwell axled rigs single triangulated is perfectly fine! The tall ass mounts are necessary for the correct separation for the ride height of a standard Rockwell rig! Simply weld a piece of 3/8" flat plate across the top of the current mount and call it good! :driving:

Rockwells607 · Mar 8, 2016

I agree most Rockwell rigs with single triangle ( I have two rigs this way) have some side to side movement. Loose heims will magnify that. If their all tight then make your bump pads bigger