I can easily see myself trying to learn how to adjust the valving on mine and trying to help others close to me. Part of the fun for me is learning how all this works.
Do springs and shocks need to be matched to perform properly?
- Thread starter Fargo
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I can easily see myself trying to learn how to adjust the valving on mine and trying to help others close to me. Part of the fun for me is learning how all this works.
From my vantage point, I think ultra4 and less than a handful of individuals have played a big role in advancing the landscape of Jeeping into what it is today.
Be prepared to remove your shocks many many times. After the initial setup purchase it's not that expensive to do. I actually have a full setup (except for shims) because I used it for setting up my LJ. I plan on learning to change the shock oil myself bare minimum to save time from having to send them across the country. More parts, more maintenance...
Feels like marketing. Did they make the same claim with the old Nitrocharger shocks? To the best of my knowledge, the coils didn't change after the Sport shocks came out
I agree. There are too many other variables vs off the shelf shock tuned for a spring. Too many vehicle setups and different terrain to say it would be better. It could be perfect for some and ride like a dump truck in another scenario.
Could spring rate matter in shock tuning? Absolutely it does. But for the most part in our application the change in rates is so small it most likely would go unnoticed.
I got the ride I wanted when I switched to Bilsteins. I am good. (Although I might try some other options down the road just so see how they all feel.) My reason for this thread was in hope that others might understand that one shock does not fix every situation. There might be more going on with a suspension when people say they have a rough ride.
I saw a thread a few days ago where a guy was describing the exact same problem I had with my BDS springs and my Rancho shocks. He also had BDS springs. The solution that everyone gave him was to buy the Rancho 5000x shocks. I don't think that will fix his problem. His problem is that his current shocks do not provide the rebound dampening that his rig needs. But nobody could see that. All they read was he had a rough ride and he needs to buy Rancho shocks. My opinion is that he would have been better off with BDS or Bilstein or even the OME that are designed for the LJ. Because I expect they will have more rebound dampening to control the higher spring rates and heavier loads. All that moving mass needs to be controlled.
I think that will vary from company to company. If you look at the Rancho catalogue they use the same shock for everything from a TJ, XJ, ZJ etc. OME and Bilstein on the other hand have different shock numbers for all these different applications. OME even has 2 different shocks for the TJ front depending on if you use the 932 or 933 spring. Which is interesting since they are the same rate of spring, but are expected to carry different loads. OME does the same in the rear. They offer 2 different rear shocks. One for the TJ and one for the LJ. Again they are expecting a heavier load with the LJ and it is paired with a firmer rate spring rate.
There is another interesting note in the OME catalogue. They state "To achieve optimal vehicle balance front to rear when Rear Spring 2949 is fitted, it is recommended that only 60047 is fitted to the front." So not only do they provide different shock options within the TJ line up, they also provide a recommendation for a more balanced shock tuning from front to rear on the LJ. I think that says a lot for OME and the importance of proper shock selection.
Shock tuning makes a difference and I believe that with a little more attention to details such as spring rate and vehicle weight, people might find that some shocks are better suited than others for their specific application. That is the only point I was trying to make in this thread. But it really got lost in the argument over spring rates.
Brianj5600
TJ Expert
I like to do stuff like that.
Exactly!!! It looks super easy to get to the shim stacks and no expensive tools.
Exactly!!! It looks super easy to get to the shim stacks and no expensive tools.
They should be a rubicon express that were a 5.5" that sagged to 3.5", they were used and I was trying to work a budget. I almost feel like I could have spent the $400 for a set of synergy/currie springs. when I change my suspension again, I will look at going with new springs that are a slightly softer rate. That I think would be optimum for my Fox shocks.
If you want a set of fixed lowers that we can push in the Synergy or Girro joints, I will make you a hell of a deal. They measure 16.25 center to center and were you would just need to get adjustable uppers...These are also Rubicon express stuff. It would get you a stout set of arms and the girro bushings. Just a thought and I need to clean out stuff I will never use from my shed. Knowing what I know now, that is what I should have stuck with but after going to Core, it was a deal that I could not turn down.
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I apologize if I missed before that you still had the fixed lowers. I might have considered them, but last night I actually ordered the Rancho adjustable arms. I really wanted the Savvy arms. But I just couldn't pass up the deal after rebate. I know many people prefer the JJ, and for good reason, but I think the D2/DDB will meet my needs. I'll create a thread on them after I get them. No need to sidetrack this thread with another hot topic like bushing choice.
Here is my take... Rate doesn't matter...much. As long as its enough to not compress fully with a loaded rig, and not so much that is doesn't compress when its supposed to, the only thing rate determines is the free length of the spring and ride height of the vehicle. IMHO, manufacturers play with rate as a way to control costs. The Currie spring is more expensive to manufacture than something like a BDS spring. A lower rate means more coils to carry an equivalent load at the same height. More coils means more material...and higher cost.
The vehicle load is the same, regardless of the spring installed. The amount of movement that happens in that spring is controlled by the shocks. if the valving is too lite, the spring will bottom out and rebound until the shock can get control of it again. If its too heavy, it will resist the motion and not allow the spring to move. But no matter what spring rate you install, its still resisting the motion of the same load (ie the vehicle and its payload vs the exciting event).
Shocks control motion, springs support weight.
The vehicle load is the same, regardless of the spring installed. The amount of movement that happens in that spring is controlled by the shocks. if the valving is too lite, the spring will bottom out and rebound until the shock can get control of it again. If its too heavy, it will resist the motion and not allow the spring to move. But no matter what spring rate you install, its still resisting the motion of the same load (ie the vehicle and its payload vs the exciting event).
Shocks control motion, springs support weight.
I have a matched set of OME springs and shocks on my P4X Frontier, and while the work great, they do use the same shock for all their different rate coils. I did put Moog coils for a TJ Unlimited Rubicon on my 2.5 SE, which gave a 1" lift, and also used the 5000x shocks. It is a solid and controlled ride for DD and some mild trails. I don't have much experience with TJ's, but all the suspension work I have on on 2nd and 3rd generation Tacoma's and 4Runners, early FJ40's and also track-day Miata's tells me spring rate is more important than lift amount and shock valving.
I think the point that often gets overlooked is the fact that the load is moving in both directions. For example, if you hit a big dip in the road, as you often find in front of a bridge, the suspension will compress as the weight of the vehicle pushes it down. But once the shock has fully controlled the downward motion, the springs are going to push back up with the same force that they were compressed with. So now the shock has to control the upward motion as well. My experience with the Rancho shock was that they were not valved properly to control this rebound motion. I can not say for sure if its an issue due to the stiffer springs, an issue due to the extra weight of an LJ or maybe its the leverage effect of the body extending beyond the wheels in the LJ. Maybe its just a personal preference issue and some people like their vehicles to spring back like that.
Your comments about load really have me thinking though. Especially since the OME shocks are based on expected extra load and not necessarily on the spring rate.
Its been awhile since I had the issue. My Bilstein shocks took care of it. But when I had the Rancho 9000XL adjustable shocks, the rear end would rebound very quickly and go well beyond its natural state of rest. Then it would settle back down. Much like any half worn out shock absorber would feel. If I went across a pot hole in the road, the rear axle would also drop very hard and very rapidly. Enough that the rear end would skip across the road a couple inches if it was during a hard slow turn around 25mph. It just felt like the shocks had no rebound control. I could crank them up to 6 or 7 and that would help, but only because they were then so stiff that they never got a chance to compress. They basically felt like an old pair of half worn out shocks. The Ranchos in front were never a problem. But in the rear they just could not control it.
You know, funny thing talking about it again. I just replaced the shocks in my Pathfinder because they were wore out after 100,000 miles. I never thought about it at the time, but they acted much like my brand new Ranchos did in my Unlimited. At least on the rebound side of things. Unfortunately the Monroes I put in my Pathfinder aren't a whole lot better. Which makes me wonder if Tenneco (Monroe/Rancho) just likes to tune their shocks to be very loose like that. But regardless they were much to uncontrolled for my Unlimited. They were quality built, but they just were not tuned properly for my vehicle.
I agree with the rebound issue on the 9000’s. I have them set at 1. I like the compression but the rebound is terrible.
What springs do you have? I've always blamed it on having too firm of a spring. But maybe its just the way the shock is valved. But no one ever talks about this issue on the forums, so I always figured my situation was unique. But maybe others just don't pay any attention to rebound. I don't know. But I'd love to hear more about your experience and setup. It might help me to put some pieces of this puzzle together.
I have run them with RE springs and now Currie. No real notable difference. I think it has a lot to do with how the shock is valved. Also what the adjustments actually do. It seems to soften both compression and rebound. Setting 2 or 3 is a lot more balanced but I like the plush ride. I do not have an issue with the rebounding on small events. Medium to large events very noticeable in the rear. For me that may be due to the front sway bar keeping the rebound to a minimum. I haven’t heard of this from guys who run the Ranchos above a #4 setting.
I will be having 12” Fox’s installed very soon as well as some rear geometry correction taken care of. Looking forward to seeing the difference.
I will be having 12” Fox’s installed very soon as well as some rear geometry correction taken care of. Looking forward to seeing the difference.
Spring rates do matter, however the lb'age range isn't all that much between the shelf TJ springs at comparable heights so your not seeing huge seat of the pants differences.
What people don't realise is that they are altering shock valving by changing shocks. One shock is maybe valved heavier and when they swap it out for another shock and their Jeep rides better it's just that the shock is valved softer.
Generally, though, existing shock valving will work within a range of spring lb'ages. So changing say 50lb on a spring doesn't necessarily mean shock valving needs to be changed.
It's true that with the huge unsprung weights being run with large wheel and tire packages, that these have the largest impact on say ride quality. Compare a TJ running same suspension with standard 29" tires to same running 35" tires and the 35" option will definately ride softer.
What people don't realise is that they are altering shock valving by changing shocks. One shock is maybe valved heavier and when they swap it out for another shock and their Jeep rides better it's just that the shock is valved softer.
Generally, though, existing shock valving will work within a range of spring lb'ages. So changing say 50lb on a spring doesn't necessarily mean shock valving needs to be changed.
It's true that with the huge unsprung weights being run with large wheel and tire packages, that these have the largest impact on say ride quality. Compare a TJ running same suspension with standard 29" tires to same running 35" tires and the 35" option will definately ride softer.
Good stuff guys. Thanks for the input.
Golluwomper - If you can report back when you get your Fox installed. I realize you are making other corrections as well, but I'd still love to hear your results. I'm really starting to think my issue might not have been the spring rates but its just how the shock is valved. It still boggles my mind though that everyone on the forum bragged about how great those 9000XLs were are and yet I hated them so much. Difference in preference I guess.
Golluwomper - If you can report back when you get your Fox installed. I realize you are making other corrections as well, but I'd still love to hear your results. I'm really starting to think my issue might not have been the spring rates but its just how the shock is valved. It still boggles my mind though that everyone on the forum bragged about how great those 9000XLs were are and yet I hated them so much. Difference in preference I guess.
Good thread. I just want to add, when I talk to guys about their valving in their TJ, I don't ask what their springs are. It doesn't change the valving I put in. There's a very small range of spring rates for the TJs. They all weigh close to the same. Just the extra weight they like to carry, and how "tight" they like their road feel to be.