RK lift-Rear wheels arent flexing up as much as front wheels?

ChattVol

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Help wanted...have a RK 2.5" Adventure series 1 lift with TT shocks and the front suspension has full travel when forklift flexing, but the rear wheels dont have the same uptravel and are about 3.5" from compressing the bumpstops when I lift the front tires to flex the rear. The lift has RK front LCA's, rear trackbar relocation bracket and extended sway bar links with stock rear trackbar/control arms. The rear shocks have about 13" of travel and fully extend well, but have 4.5" of shaft left for uptravel when the rear is compressed...so I dont think the shocks are a limiting factor.

A good friend suggested I disconnect the rear sway bar and retest it...but it's a pain to access a forklift to retest. Does anyone know if the stock rear control arms or trackbar can limit up travel like this? Or maybe it is the rear sway bar binding? Thanks for your input.

 

chevymitchell

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A picture would help. What do your springs look like when they're full compressed?
 
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ChattVol

ChattVol

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A picture would help. What do your springs look like when they're full compressed?
This is the rear as compressed as it will go...in this pic, the front tire is lifted to the point that it started to lift the rear tire on the same side.
ie9YKjp.jpg


For comparison, here is the rear tire lifted and the
front suspension fully compressing the bumpstop. The pic doesnt show it well...the front is compressing about 2" further.
o6wcaNc.jpg
 

chevymitchell

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The only thing preventing you from more articulation is the bump stop. If you feel like you have room for more (Shock travel, tire in the wheel well, control arm bushings), then take one of the bump stop pucks out and try again. You can adjust the pucks to control your up travel. The front and rear are going to move differently. You can't really compare the two to each other. I would adjust the bump stops to the minimum amount required to keep things from bumping and rubbing.
 
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ChattVol

ChattVol

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The only thing preventing you from more articulation is the bump stop. If you feel like you have room for more (Shock travel, tire in the wheel well, control arm bushings), then take one of the bump stop pucks out and try again. You can adjust the pucks to control your up travel. The front and rear are going to move differently. You can't really compare the two to each other. I would adjust the bump stops to the minimum amount required to keep things from bumping and rubbing.
Thanks for the input...the front suspension almost fully flattens those white pads at full compression. I have atleast 4" of uptravel space left in between the rear tire and rubi fender. Maybe the rear suspension doesnt flatten the bumpstop pads bc there is less weight in the rear of the jeep with the motor being up front?
 


chevymitchell

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Thanks for the input...the front suspension almost fully flattens those white pads at full compression. I have atleast 4" of uptravel space left in between the rear tire and rubi fender. Maybe the rear suspension doesnt flatten the bumpstop pads bc there is less weight in the rear of the jeep with the motor being up front?
The front hits the stops differently and the front is wider, so there's more leverage to compress them, as well. The front will hit the stop at an angle and the rear will hit it more square. If you're really curious, remove all of your bump stop pucks in the rear and retest. Just watch your driveshaft. It'll hit the gas tank.
 

Rock Krawler Suspension

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Thanks for the input...the front suspension almost fully flattens those white pads at full compression. I have atleast 4" of uptravel space left in between the rear tire and rubi fender. Maybe the rear suspension doesnt flatten the bumpstop pads bc there is less weight in the rear of the jeep with the motor being up front?
Exactly right, the rear of the JL is very light and the OEM uses the same foam density front and rear. If you flex into it with the axle moving at speed like a big rock off road or a large pothole on road, the foam will compress. If you want to test, you can simply remove the foam bumps to see if it will flex farther. The rear arms should not a limiting factor for you but will resist articulation to an extent.
 

stil2low

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Thanks for the input...the front suspension almost fully flattens those white pads at full compression. I have atleast 4" of uptravel space left in between the rear tire and rubi fender. Maybe the rear suspension doesnt flatten the bumpstop pads bc there is less weight in the rear of the jeep with the motor being up front?
Have you loosened and re torqued the rear control arm bolts after the lift? Of not the bind in the bushing can be limiting the travel some
I’m running just EVO shock extensions at the moment with my RK but also have their rear uppers from my JK on. With 35’s I should be able to get away with just the pad and puck
I’d take a puck off and redo the control arm bolts (if they haven’t been reset after lift) and see if you get more up travel. If not some rear arms will help with the misalignment

B412286D-A0D7-46EA-8C06-D75E22ED46DE.jpeg
 
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ChattVol

ChattVol

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Have you loosened and re torqued the rear control arm bolts after the lift? Of not the bind in the bushing can be limiting the travel some
I’m running just EVO shock extensions at the moment with my RK but also have their rear uppers from my JK on. With 35’s I should be able to get away with just the pad and puck
I’d take a puck off and redo the control arm bolts (if they haven’t been reset after lift) and see if you get more up travel. If not some rear arms will help with the misalignment

B412286D-A0D7-46EA-8C06-D75E22ED46DE.jpeg
Yes...I had already loosened all control arm bolts and rocked the jeep back and forth a good bit and retorqued. I'll remove a puck and try again.

 

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