Help - Ridiculous Ride (another FJ40 suspension question) (1 Viewer)

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LucyProject

FJ Adventures
Joined
Feb 10, 2019
Threads
5
Messages
44
Location
Centralia, WA
Website
www.youtube.com
Okay, brain trust. I have a very specific suspension scenario, and I'm hoping one of you had the exact same scenario and can point me to the perfect solution. I have 79 FJ40. The previous owner did a spring reversal on the front, and lifted the rig around 2.5". It appears he kept the original springs (I'm not sure), and did most of the lift via shackle extensions (maybe). The PO also installed Rancho RS5113 shocks. The front shock compress a distance is 13", the extended length is 20.3", and therefore travel is 7.3". All-in-all, my rig flex's pretty well, but it rides as rough as anything I've ever driven - its downright violent over potholes. Sometimes it seems like my front and rear ends are bolted to the frame. Anyways, I was considering some Bilstein 5125's since some have used them and said it helps. However, I wouldn't know if I need 0"-2" lift shocks, or 4" lift shocks for my rig. Also, I'm not sure if the Rancho shocks are the problem. Any help would be greatly appreciated. My wife has some brain tumors, as well as some damage due to surgeries, and she is super sensitive to the jarring action. I'd love to soften the rig up some if not a lot.

To recap my problem:
1) Front Spring Reversal
2) Original Springs
3) ~2.5" Shackle lift?
4) Rancho RS5113 shocks
5) Crazy rough riding highway and trail
6) Brain tumors

What I need to find:
1) Shock recommendations (product numbers if possible)
2) Spring recommendations (for spring reversal with product numbers if possible)

Thanks in advance. And, I apologize if this scenario has been discussed before. I struggle finding anything on this site, and when I do find something, it tends to be a decade old with a bunch of broken picture links, and out dated references.

YouTube video of typical offroading (slow and steady):



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The only way to know which shock you need would be to flex it and take measurements and then search shock spec's to find one that will meet your spec's.
 
Idk maybe leads are worn too much, so ride is rough? I’m not a suspension tech so I can’t be sure, but usually people look at the leafs when the ride is rough.
 
Idk maybe leads are worn too much, so ride is rough? I’m not a suspension tech so I can’t be sure, but usually people look at the leafs when the ride is rough.
Very rough. On highway and gravel roads, there doesn't appear to be any absorption of bumps. Its like the shocks or springs are way to stiff, and the only move when the terrain is extreme.
 
It's hard to tell from the pictures but I don't think your springs are OEM and the shackles are a bit long. Do you have 3 to 4 thick leaves in your springs or 6 to 7 thin ones?

Tire pressure and overtight bushings can cause rough rides too. Maybe look at a few suspension kits like Skyjacker, Old Man Emu or HFS.

FWIW - I did an HFS 4 inch lift on mine years ago and am still happy with it. Kit came with shocks, shackles and greasable hardware if I remember correctly.
 
The only way to know which shock you need would be to flex it and take measurements and then search shock spec's to find one that will meet your spec's.
Yeah - I can figure out travel distances. I'm just not sure if I have a shock problem, leaf problem or both problem. I was hoping to find someone with a similar set up that could tell me if the have the same problem and/or knows how to correct it. I've had a few old jeeps that have basically the same suspension set up, but road MUCH nicer on and off road.
 
after viewing the video, it doesnt appear to be the springs, as it flexs nicely over everything. if it was the springs being to stiff or shackles being over tightened it wouldnt flex as much as it does. it's either the shocks being to stiff, and being 5000 series ranchos, that very well might be the case, or you are unfamiliar with the way a short wheel base with leafs on both ends rides.
remove the shocks entirely and go for a ride....now it will be much more bouncy and i would NOT recommend taking it on the highway strictly around town to see if the ride isnt softer.....this is merely a diagnostic procedure not a long term solution.
 
It's hard to tell from the pictures but I don't think your springs are OEM and the shackles are a bit long. Do you have 3 to 4 thick leaves in your springs or 6 to 7 thin ones?

Tire pressure and overtight bushings can cause rough rides too. Maybe look at a few suspension kits like Skyjacker, Old Man Emu or HFS.

FWIW - I did an HFS 4 inch lift on mine years ago and am still happy with it. Kit came with shocks, shackles and greasable hardware if I remember correctly.
I have the "3 to 4" leaf packs. I haven't loosened anything up to see if anything is seized or over tight. I guess that should be my next step. I've had a few old jeeps that have basically the same suspension set up, but were MUCH nicer on and off road.
 
after viewing the video, it doesnt appear to be the springs, as it flexs nicely over everything. if it was the springs being to stiff or shackles being over tightened it wouldnt flex as much as it does. it's either the shocks being to stiff, and being 5000 series ranchos, that very well might be the case, or you are unfamiliar with the way a short wheel base with leafs on both ends rides.
remove the shocks entirely and go for a ride....now it will be much more bouncy and i would NOT recommend taking it on the highway strictly around town to see if the ride isnt softer.....this is merely a diagnostic procedure not a long term solution.
I was leaning the same way. It really handles extreme terrain well, but is down right violent on gravel roads and asphalt. I've had a few old jeeps that have basically the same suspension set up that road quite a bit better. I don't expect a Cadillac, but based on my passed experiences, it really seems like something is off.
 
Its probably those springs. I know someone who has those. Super rough ride.
 
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Its those springs. I know someone who has those. Super rough ride.
The springs or the shocks? Because, I don't even know what springs they are, haha... But if you are talking about the Ranchos, then your comment was the one I've been waiting for, and the reason I peppered the internet with posts and comments world wide, lol. If you are talking about the springs, then what kind are they?
 
The springs or the shocks? Because, I don't even know what springs they are, haha... But if you are talking about the Ranchos, then your comment was the one I've been waiting for, and the reason I peppered the internet with posts and comments world wide, lol. If you are talking about the springs, then what kind are they?

Spring packs, I think they were sold by Rough Country back in the 90s.
Rancho shocks were always kind of stiff, no matter their age, used to have them too. 🙂
 
Spring packs, I think they were sold by Rough County back in the 90s.
Rancho shocks were always kind of stiff, no matter their age, used to have them too. 🙂
Oof you may want to get a skyjacker kit or OME kit for a better ride to replace the older rough country. Surprised the 90s rough country springs lasted this long
 
Oof you may want to get a skyjacker kit or OME kit for a better ride to replace the older rough country. Surprised the 90s rough country springs lasted this long
Ah... So you recognize the springs? I had know idea what there are. But, I have heard others complain about the "rough" country springs before - just didn't know I had them.
 
Ah... So you recognize the springs? I had know idea what there are. But, I have heard others complain about the "rough" country springs before - just didn't know I had them.
Rough country is a budget company that makes lifts and stuff. Manufactured in China. Low quality but it’s the cheapest stuff around. Mostly high schoolers use rough country. Have a great warranty though. Unlimited mile lifetime warranty on current lifts.
 
Spring packs, I think they were sold by Rough Country back in the 90s.
Rancho shocks were always kind of stiff, no matter their age, used to have them too. 🙂
You recognized them as Rough Country as well? Thats 2 now.... That may just be the problem then. Grr... That's gonna take a little more coin than just new shocks.
 
You recognized them as Rough Country as well? Thats 2 now.... That may just be the problem then. Grr... That's gonna take a little more coin than just new shocks.
Also, another thing you can try is removing one leaf. People do that and say the ride is much better, not sure if it will work on worn shocks though.
 
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You might have Rancho springs, hard to tell just from the pictures but they do look similar to mine


Two things you should check.

1. Make sure the shackles aren't tightened too much to cause binding. When I first got my cruiser it felt the same way, like the truck didn't have any springs just a solid block between the frame and the axle. Loosen the shackle bolts a turn or two (temporarily) and see if that improves the ride. If the bolts are overtightened they will pinch the springs and bushing and prevent them from flexing.

2. It looks like the bushings are shot, the leafs aren't centered on the shackle holes. I just replaced my bushings and it made a noticeable difference in the handling. My old bushings were hardened like a rock, the new ones really softened up the small bumps. It's still a short wheelbase leaf spring vehicle, so it's never going to be a smooth ride, but every little bit helps. If your bushings look like this it's time to replace them

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Also x2 on removing the shocks and test driving it. That will at least narrow down where the problem is coming from.
 
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