Agboss

Hi Jeepers,
I recently bought a JK 2011 2 doors, factory 2" lifted with Mopar/Lovell blue springs and, what I believe, KYB gas-a-just shock absorbers. I have Nitto trail grappler 34 tyres fitted on it
I found the drive a bit bumpy on-road, but I got used to it (my girlfriend didn't) and I thought it was something specific to Jeeps (that is my first Jeep) or related to the lift kit, which could make it more adapted for off-road driving... But I was totally WRONG. Last weekend, I've been off-road driving on beach, mud and rocky tracks and and that was literally horrible (even with the tyres at 18 psi): loss of control on washborded roads with the rear wheels drifting, could feel the smallest rock on the track, the JK shaking and bouncing like hell, my girlfriend smashed from left to right... horrible!
After a bit of reading, I found out that having KYB shocks is pretty much the same as having no shock absorber. So, I'm definitely planing to change these bloody shocks and get some Rancho 9000XL or Bilstein 5100.
1/ Is that a good choice? Which one is best? (Maybe I'm wrong again, but as I'm driving both on and off-road, I thing the adjustable ranchos will be good for me...)
2/ Are the Mopar/Lovell blue springs that bad? Do I need to change them if I changed the shocks?
3/ What are the best springs for rancho 9000xl?

I really want on comfortable drive both on and off-road, without loosing control on the first washborded road.
Thank you very much.

kmrtnsn

First off, what is the air pressure in your tires? Second, THE Jeep JK has rigid axles, it isn't going to float as smoothly on washboard roads as a vehicle with full or front independent suspension. I've heard good things about the Rancho 9000's but short of going to a coil-over front suspension, slowing down and airing down will give you the best improvement for the least amount of money.

JK08MCS

What gas pressure you have in those shocks? Just try to drive it a short distance with out front or back shocks. Just to see if its the shocks or your springs. On the street I run my tire pressure 22 psi and off road 12 psi.

Agboss

on road, I usually have 30 psi, and 18-20 off-road. It's not really about money, as long as I can improve the stability/driving. I'm just wondering if changing the shocks may improve it.
And slowing down, that's what I was forced to do to stay on tracks, but my friends were so pissed off of waiting for me...
It is also bouncing a lot at lower speed, don't think it's good for the vehicle to be shaken like that.

Agboss

Don't know for the gas pressure in the shocks, there is no sticker, I just have found the name on the log book, but no reference number.
It could be a problem of too much air pressure in the tires then? but i've been told this 30/18 psi values are good for the nitto trail grappler... I'll try to reduce the pressure a bit more then

kmrtnsn

The right shocks may (emphasis on right and may) help. Curious, just what are your faster friends driving?

Agboss

Fj cruiser and Pajero 2 doors

kmrtnsn

You are never going to compete speed-wise on rough roads against vehicles with independent front suspensions, period. Your Jeep was not made for that. That is the drawback to a rigid front axle.

tjkamp

I'm on my phone, so I can't access profile info as easily, but are you in a 2-door or 4? I just put the 5100's on my 2-door, and they are fairly stiff, but not as stiff as you are describing. I really like a stiff shock, so it works for me. I've heard nothing but good things about the rancho 9000's. And the adjustability has to be nice.

Again as stated those vehicles have IFS, and that does make a difference, but the JK shouldn't be that bad.

I would say the easiest starting point would be to park the Jeep, climb up on the front bumper, and try to use your weight to flex the front suspension up and down, to get a feel for how much movement it has, then disconnect the lower shock mounts (it may take a jack and some stands to remove pressure to get the bolts out), and then do the same front bumper activity and see how much more movement you get. If it is dramatically different, than it is the shocks, if it is still very similar, then it could be the springs. Generally, in my experience, ride quality is much more dependent on the shock than the spring, although they both contribute.

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tjkamp

Sorry, just saw the 2-door part.

Some people argue that the 5100's are too stiff for a 2-door, but I really like mine. I also have around 200 extra lbs. on the front end with my bumper/winch combo though.

Happy Jeeping!

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