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Discussion Starter #1
So I installed my lift on saturday, with alot of help from my brother in law and his friend. I got the 2.5" radflo's with the deavers in the rear. Greg also put on the 750lb spring instead of the 650 because I'm planning on doing a shrock bumper eventually.

The only thing weird I've noticed is that whenever I go over a sharp bump, like a speed bump, or hit a pothole, it kind of thumps when the shock is extending. I'm thinking it's hitting some sort of bump stop. Is that correct? Is this necessarily bad? I don't mind it so much, except I'm paranoid because the stock shock I removed had the top blown off on it. (overextended?) I don't want to do the same thing with the new setup. :D
 

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The thump is most probably your stock UCA hitting the coil bucket. I know with the 2.5 radflos you arent supposed to have any contact, but I think its pretty much inevidable when you hit large bumps. If the shocks are designed to be fully extended before you have Upper controll arm contact, then I say dont worry about it. those shocks are tough as nails and cannot even compare to your stock shocks.
 

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Discussion Starter #3
Ahhh ok. If it's the UCA contact, is that going to cause any mechanical problems, or is it just annoying? I don't mind it that much.
 

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there should be no UCA contact going over pot holes, or bumps on the road. it's more of an annoyance then anything. but i would recommend you try to isolate the problem and if it is coming from the coilovers contacting something give greg a call and see if he has a solution for you.
 

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Did you take your rear sway bar off? If not it could be that. Also did you check that you installed the deavers the right way? I ask because I did the same setup as you and got no directions on how to install and later on it turned out that you can but the deavers on backward.
 

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Up front, my shorter Radflos have no contact. I have the 650 lbs springs. I wonder if they are just really stiff so you think they are hitting something? Mine are a bit stiff, which seems to be getting a little better after a couple hundred miles. Also, if you adjust them a little bit lower, they will ride uch better, and minimize contact chances. Call Greg up and talk about the contact, unless you were sent the wrong ones, I highly doubt it can be contact.
 

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It is definitely the UCA contact, to completely get rid of this you will need to replace your UCA's with aftermarket ones. To "soften" the blow of the contact, you could put some rubber hosing around the top of the coil bucket, if you do a search you'll find the "How to" on this. I've just got the Calmini spacer/shackle lift on my rig, and I used some heavy duty rubber hose that I got at the Home Depot, and lined my coil bucket with it, helps out a lot until I'm able to convince the wife to spend $500+ on the TC UCAs. It's taking a while, but I think she'll be sold on it after my deployment.
 

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Discussion Starter #8
silver_sancho said:
Did you take your rear sway bar off? If not it could be that. Also did you check that you installed the deavers the right way? I ask because I did the same setup as you and got no directions on how to install and later on it turned out that you can but the deavers on backward.
I didn't disconnect the rear sway bar, but this is definitely from the front suspension. It does it when the front wheels droop after hitting a speed bump. Luckily there were nice arrows drawn on my deavers so I'm certain I put them on the right way. :)
 

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again, you should get NO UCA contact with the shorter radflos.....if this is the problem call greg. he replaced one of my coilovers because it was causing contact. you do not need to spend another $500 on new UCAs nor do you need to do a temporary fix.
 

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Discussion Starter #10
azterra said:
Up front, my shorter Radflos have no contact. I have the 650 lbs springs. I wonder if they are just really stiff so you think they are hitting something? Mine are a bit stiff, which seems to be getting a little better after a couple hundred miles. Also, if you adjust them a little bit lower, they will ride uch better, and minimize contact chances. Call Greg up and talk about the contact, unless you were sent the wrong ones, I highly doubt it can be contact.
It could be this too, it's hella stiff in front, especially since I was driving it around with a blown shock for who knows how long. :) I'll give Greg a call and see what he thinks. I also didn't adjust them at all from how he sent them, but it looks like it's giving the proper amount of lift. (front is slightly lower than the rear)
 

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jay, they don't know that the # usually refers to the shock diameter, not lift height.
So, yeah, there's no way they fit 2.5's on a 4wd!
 

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Discussion Starter #14
Ok, so I did some more testing on speed bumps, and it seems like the truck is actually launching off them at low speeds, lol. I think it may be due to the extra stiff springs and no winch bumper yet. I also took a look at the coil bucket, and I didn't see any indication that the UCA was hitting it. (no scratches) Also, if I hit speed bumps faster, it smooths it out quite a bit, so I think the solution is to just drive faster in parking lots. :D
 

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UCA contact has nothing to do with the spring, it has to do with the shock length. You can cheat by putting a long shock on and adjusting the spring so that the vehicle does not sit as high. Only problem with that is if you drop the front wheel all the way, for what ever reason, you will get contact. If the shocks are the correct length, no matter what you do (short of breaking the shock) you will not get UCA contact. The shock acts as the droop bump stop.

I don't know if I am explaining so people can understand, but just sit for a minute and picture how the front suspension works.

You have a lower control arm that pivots at the frame. You have an UCA which pivots at the frame. At the outside end of these arms you have a steering knuckle between them with a ball joint at each end.

This assembly as it sits can move up and down freely. The only limit is the up travel bump stop on the LCA and the fact that the UCA will hit the coil bucket (which is attacked to the frame) on the down travel.

So, if you leave the system as is and not put a shock in it. You lower the vehicle down on it's wheels and the LCA will rest on the bump stop. If you raise the vehicle off of it's wheels, the UCA will rest on the coil bucket.

Now, put a coil over shock in the mix. The bottom of the shock attaches to the LCA. The top of the shock attaches to the coil bucket (remember, the coil bucket is part of the frame and is static).

Now, if the shock is too long, when the vehicle is raised, the shock will extend, but the UCA will hit the coil bucket before the shock fully extended. If the shock is too short, as the shock will be fully extended before the UCA hits the coil bucket.

There is going to be a happy medium when it comes using stock UCA with after market shocks. You don't want the shock to be too short or you are losing some downward travel, but you don't want them too long or you have UCA to coil bucket contact.

The aftermarket UCA's (PRG and TC) both have a downward travel bump stop built into them to soften the UCA to coil bucket contact should it happen.

I hope that wasn't too long winded and I hope folks understand.
 

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Jason,

You should post that in a sticky. :yes:
 

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Yes, definitely helpful.

So my question is, is there a tremendous performance advantage in going with the 3" Radflos with the TC UCA's over the system that was installed in this thread..ie the 2.5" with stock UCA's??

Costs aside, my goal is to raise my front end by about 3", and IF the lengthened amount of travel that is advertised with the TC UCA's is worth it from a performance perspective, then I can see forking out the extra $$ on it.

If one can get similar results with the 2.5" radflos and stock UCA's, then it would be kinda foolish to spend the extra money.

What sayeth the suspension shamen?
 

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You will gain additional drop (down travel) with the aftermarket UCA and longer shocks. Because of this additional down travel, you get more lift. How much more is dependent on how long the shock is and how much clearance you gain with the aftermarket UCA.

With our system, you have to take rob Peter to pay Paul.

The more lift you get, the less down travel you get. This is true no matter which UCA you are using. If you replace the UCA and shocks (to longer shock) and adjust them to the stock ride height, you will gain drop.
 

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Discussion Starter #20
From what Greg was saying, you'll get a max of 3" of lift with the new UCA's, and 2" of travel over stock. The stock UCA config will give you up to 2.5" of lift, and an additional 1" of travel over stock.

I decided to just save $500 bucks and go with the stock UCA option. Also the high maintenance of the new UCA's seemed like a pain. (wipe them down every time you refuel)
 
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