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Discussion Starter #1
Hello, I am new here and have searched and not found a thread addressing this, so if there is already one please point me to it.

With many of the leveling kits going on top of the strut assembly between it and the body I don't understand why this couldn't also be done with the QL.

Is it because the system will sense the change in height and just raise the back? If that were the case it would raise the back when driving uphill.

Any insight into this would be greatly appreciated.

I have a 2013 Trailhawk and am planning on putting tires with a 31.5 height and want to level the front out to help avoid rubbing.

Thanks
Sean
 

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The Jeep has a sensor that measures the compression/extension of each wheel and adjusts the air pressure to bring them into a preset range. It is not measuring height. The QL will cancel out the leveling kit or fail trying. I have not read of anyone attempting to modify the sensor.

The front suspension may reach its bump stop (extended fully) when a leveling spacer is added to OR2. You would end up with zero rebound, not that you have that much now. Could be a wild ride :).
 

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Discussion Starter #3
What if a modification was done to extend the lower part of the air shock? I was looking at it when they were swapping out my wheels and noticed the lower part has a sleeve that fits around the bottom of the shock and is welded up tight against a ridge in the shock.

If this weld was ground down and then the sleeve slid down lower, with a tight fitting piece of steel pipe cut to 5/8 - 3/4 slid between the original ridge and the top of the sleeve it'd effectively lift the front end by that much. It could all be welded back to ensure it wouldn't move, and the ridge would take the pressure and not the weld.

Make sense?
 

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The sensor on each corner is a ride height sensor linked to the control arms. If you used a spacer on the strut to raise the ride height, the sensor would indicate it needed to be lowered, and drop the pressure in the air springs. The right way to level would be to build a longer link to the ride height sensor (similar to the links sold for land rovers)
 

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Discussion Starter #5
Well what I am thinking of doing would be the same as driving the front tires onto something 3/4 of an inch high. It wouldn't know that the strut had been lengthened below the air shock... or at least I can't think of how it would know. I will try driving both front tires up onto a block of wood as a way to test it and see if it lowers the front end.
 

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That is just going to look like driving up an incline or hill or over a bump. The front end doesn't lower when you drive up a hill right?

The height sensor shown below attaches between the frame and control arm and the system adjusts the suspension to keep the same position on the sensor (the distance between the frame and control arm). It works similar to throttle position sensor. There is an averaging/lag so the height adjustment is not responding to bumps and dips. What you may want to try is to trick the sensor by replace the link with a longer one, but that will take all rebound out of ORA2 height. Extend the link too much and if you ever run OR 2 height, the system will be squeezing the heck out of the rebound bumpers trying to adjust. If you never use OR 2, well not an issue.
 

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Discussion Starter #7
THANK YOU COLDCASE!!!

I actually decided that instead of raising the front I wanted to drop the back so I located the sensor on the rear (behind the air shock) and removed the 2.5 inch long control arm. Through trial and error I was able to find out that if it was .25 of an inch shorter it would drop the back about 5/8 of an inch. So now instead of a 7/8 -1 inch difference in height it is only 1/4 - 3/8 higher in the rear.

I will most likely post pics as well as detailed instructions in case anyone else wants to do this. Now that I know what to do with quick dry epoxy or a small welder this mod could be done in less than an hour for both sides.

Thanks again for the tip on how it senses the height.

Sean
 

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That's excellent news mate, I thought it wasn't possible to do but I'm glad you figured it out. Looking forward to your instructions on how to do it.
 

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Hi, have you encountered any problems with the levelling of the QL, I just want to check it all works ok before doing mine.
 

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Discussion Starter #10
No problems at all... shortening the rear sensor rods just a little bit worked perfect to drop the rear. I've been developing an adjustable rod to allow for fine tuning as well as returning it to it's original state. Let me know if you'd have interest in a set. I could ship them to you and then have you send me yours after installing the adjustable ones.
 

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I'd be interested in a set to lower the rear about a half inch.
 

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Discussion Starter #12
The problem is in order to get the link rod Jeep part you have to buy the whole sensor assembly at almost $100 each, so to do the rear it'd be $200...
 

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Eh, not worth it to me for that much.
 

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There are very specific standards for high speed handling.

If you ever saw the Moose Pull test some Scandinavians made up and do for their auto blog, and how the JGC did compared against some other popular SUV's, you might not want to mess with the suspension.

Thing is this moosepull test, was sorta bogus, it exceeded the accepted standards for high speed handling. In the past many SUV's rolled over or came so close to rollover they had to dive out of the test. The JGC didn't roll over, but it blew a tire (in fact didn't damage the tire, it was so extreme it pulled the tire bead away from the rim to loose most of the air in the tire, they just had to pump the tire back up).

Jeep took the same car to testing facility and it passed the SAE/IISM tests with flying colors.

What it came down to, the SUV's that passed the test wouldn't even come close to the Jeep in off-road ability, but if you don't off-road and want the safest vehicle, you'd want one of those other SUV's.

So if you're going to mess around and trick the ride height on the air suspension that adjust itself according to speed to assure the best high speed handling. Then you better consider it the same as a lift kit, i.e. the OEM handling characteristics are compromised and you should drive as such.
 

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Their assessment is wrong and misleading IMO. The JGC passes standards tests to ensure safe high speed handling. They, and their subjective non-standard test, is not qualified to declare a vehicle safe or unsafe.

They can only legitimately claim that in extreme maneuvers they found the VW and Volvo vehicles to be safer than the Jeep.

Again, this is the design compromise you make if you want the off-road ability of the Jeep that the VW and Volvo do not have.

But, something to consider if you're going to mess with the suspension of the vehicle with ride-heights, wheel travel and stance, you could have a big surprise if you try to make radical and extreme maneuvers at high speeds after messing with those things.
https://www.youtube.com/watch?v=zaYFLb8WMGM
 
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