The Weekend Fun Build

The new front bump stop extensions are in.

IMG_20190906_132536.jpg


And the front springs are in with the leveling spacers, although I had to break down and use a spring compressor to get the second spring in. It was an epic battle, but I figured I should stop fighting the spring and before I did something stupid.

IMG_20190906_185746.jpg
IMG_20190907_071038.jpg


That means I'm on the last push to finish everything up. Next step is to reassemble everything else in front, then figure out the rear bump stops.
 
I finished up the front end yesterday. Everything is back in place and properly torqued. Steering got realigned. Fittings all greased.

IMG_20190907_113145.jpg


It's time to set the bump stops for the rear axle. Since it's going up and down a lot, I extended the axle breather hose by a couple of inches so the hose isn't pulling off the fitting anymore. Thanks, @bobthetj03!

IMG_20190907_120542.jpg


The 31" tires still fit fine in the rear fenders, but that's nothing new. Also, the bump stops hit the axle pads at full flex right before the shocks hit full compression. And the new track bar just clears the diff with the right axle pad on the bump stop. So that's all good.

IMG_20190907_125917.jpg
IMG_20190907_135014.jpg
IMG_20190907_135648.jpg


Full bump on the rear axle was a big surprise, though! The shocks hit full compression with a big gap between axle pad and bump stop cup. I ended up with a 1" gap on the left side, and a 1.5" gap on the right side. There's nothing bent or out of alignment back there, so I can only figure that the difference in the gap has something to do with the track bar shifting the axle as it moves up.

IMG_20190907_140103.jpg


Unfortunately, I didn't plan for extended rear bump stops. If it were just a 1/2" or 1" gap, I'd make something to fit and move on. But making 1.5" bump stop extensions from the materials I'm prepared to work with seemed half-assed. Teraflex makes some 1.5" rear extensions that aren't expensive, so I ordered those.

https://www.amazon.com/dp/B006D9VZXI/?tag=wranglerorg-20

Don't order that part from Amazon, though, because it's twice as expensive as everywhere else.

Putting the rear end back together is the only thing left to do, so now I have to wait for that part to come in.
 
  • Like
Reactions: JMT and bobthetj03
They are too long. With those bump stop extensions and those shocks you're pretty much setup for 33's. With a shorter shock, you should be able to run 31's with no bump extension in the front, and only 1" in the rear. Just an FYI.
 
They are too long. With those bump stop extensions and those shocks you're pretty much setup for 33's. With a shorter shock, you should be able to run 31's with no bump extension in the front, and only 1" in the rear. Just an FYI.
On paper, the Rancho shocks looked like a good fit, but they are a little long. On the other hand, the only shorter shocks I was considering were the OMEs and I had already decided not to go with them.

At this point, I'm hoping that I still have a good balance of up and down travel. If that's really out of whack, I may have to make some changes.

Anyway, the thought had crossed my mind that I could easily fit 32s with this setup and probably fit 33s with a body lift.
 
  • Like
Reactions: Nickgsjeep and JMT
32's actually would be a good fit with this setup. If you are against a BL, a small 0.5" BL might give you just enough to drop the bumps by 1". Your setup right now gives you 4.5" of up travel. Stock is 4", so you at least have a bit more than stock.
 
  • Like
Reactions: JMT
32's actually would be a good fit with this setup. If you are against a BL, a small 0.5" BL might give you just enough to drop the bumps by 1". Your setup right now gives you 4.5" of up travel. Stock is 4", so you at least have a bit more than stock.
I'm not opposed to a BL. That may come later. My bump stops are as long as they are because they're protecting the shocks, though, not protecting the body from the 31s.

The issue with 32s is that I'd be buying new tires and probably new wheels, and my gearing is already not so great with 31s. I could maybe run some JK take-offs with adapters if I wanted something cheap and could put up with the gearing. I'm not really excited about that, though.
 
Have you looked at the 0" lift Ranchos? I know you'd lose a little down, but you'd gain that up and be able to lose those bumps. Might provide a move equally biased shock travel, and then just stick with the 31's.
 
Have you looked at the 0" lift Ranchos? I know you'd lose a little down, but you'd gain that up and be able to lose those bumps. Might provide a move equally biased shock travel, and then just stick with the 31's.
I did look at them before I picked the longer shocks, but I know some things now that I didn't know then.

I don't think I'd be able to use all the up travel in the RS55128 front shocks because I'll need at least 1" bump stop extension up front to keep the tie rod from hitting the track bar. And the RS55240 rear shocks are only 3/4" shorter.

I'm not really second guessing the build at this point. Unless something really doesn't work, I'm going to run what I have for now and see how things work on the trail. And if that means I'm halfway toward running 33s, maybe that's not a bad thing.
 
  • Like
Reactions: JMT
I'm still waiting for the rear bump stop extensions to come in, but I learned something today anyway. I had noticed that one of the rear OME coils was 1 cm taller than the other, so I asked ARB about it.

IMG_20190907_151702.jpg


Here's what they said:
Hello! Thank you for going with OME. These Coils are an “A” (taller) and “B” set. Most vehicles take both taller Coils on the driver side, however with the TJ application they are staggered; A on the driver side in front and A on the passenger side in the rear. Hope this helps. Have a good day!

Fortunately, I had already figured I would stagger the taller coils, so I had put the slightly taller front coil on the drivers side. So that was a lucky guess.

Also, kudos to ARB for having responsive, friendly, and informative customer service!
 
  • Like
Reactions: JMT
On mine with several sets of OME coils, I always ended up with both tall coils on the passenger side.
 
  • Like
Reactions: fuse
While I was waiting for the rear bump stop extensions, I had a little detour from the build and worked on accessories instead.

The local Jeep club is doing a run through Death Valley in November and the run requires that you carry extra fuel. I picked up a nice jerry can, but didn't have anywhere to put it. So I got a hitch extension with a step, drilled a couple holes, and mounted a holder on it.

IMG_20190912_140446.jpg


I'm pretty happy with that setup. The run is not supposed to have a lot of big obstacles, so compromising departure angle shouldn't matter.
 
  • Like
Reactions: Nickgsjeep
Rear bump stop extensions arrived Friday. I put them in today and finished up the lift install.

IMG_20190914_065150.jpg


The 1.5" extensions are doing exactly what they should. The pic above is with the rear axle fully stuffed. With either end flexed, the shocks come out with just a couple millimeters of stroke left when the bump stop cup hits the axle pad.

After that, it was just a matter of putting the springs back in and torquing all the bolts around the rear axle back to spec. Here's the final result!

IMG_20190914_101906.jpg


I think it looks good. You notice it's lifted, but not excessively.

IMG_20190914_102008.jpg


The rake looks good too. Still a little higher in the rear, but not too much. I'm really glad I added that 3/4" spacer to the front springs.

The first test drive went well. The R5000x shocks are a big improvement over the old R9000s. The R9000s always seemed harsh, but the R5000x shocks seem to have better small bump compliance while being plusher on the big hits. Maybe I'm imagining it, but it seems like there's less body roll in the corners too.

The front alignment came out fairly well. Steering is fine, and the steering wheel is only just a hair off center.

Comparing measurements to before the lift, I ended up with about 2.8" of lift in front and 2.2" in back. Right on the money for a 2.5" lift.

The front shocks are sitting right about mid-stroke (53% up / 47% down). The rear shocks have a bit more up stroke than down stroke (69/31).

One thing I learned during the install is that rear shock position does not have a linear relationship with axle position because the angle of the shock relative to the axle is always changing. So I'll have to measure the rear axle droop to see how much up/down travel I really have.
 
  • Like
Reactions: Nickgsjeep and JMT
I measured rear axle droop the other day and found that I'm a little closer to mid-stroke on the shocks. The rear has about 60/40 up/down travel. That seems acceptable.

My baseline for ride height is with the hard top on and the rear set in. That's the DD configuration. On the trails, it's usually top off with additional passengers in the rear seat, or top on with the rear seat out and more tools and gear in the back. I figure the loads are all in the same ballpark.

I'll just count the extra up travel in the rear as a little extra capacity for heavier loads.
 
So this happened yesterday.

IMG_20190921_155726.jpg


It became clear that I was getting unacceptable driveline vibrations after the lift. I was getting a throbbing hum from the back of the Jeep from 25 to 35 mph and again from 50 to 70 mph. The hum got louder with more throttle, quieter with less throttle, and didn't change when I changed gears, but did change with speed.

To me, that looks like the symptoms of a misaligned pinion. I did measure driveline angles before and after the lift, and I had good u-joint cancellation before the lift, poor cancellation after the lift.

I figure there are a couple of ways to deal with this:

* Drop the transfer case and possibly add a MML to reduce the driveshaft angle and move the pinion angle in the right direction.
* Get adjustable rear control arms and rotate the rear axle by about 4 degrees to get good u-joint cancellation.
* Get a SYE, DC driveshaft, adjustable rear control arms, and a rear track bar relocation bracket and redo the whole rear driveline.

I'm supposed to be leading a trail run today, so I ran out to a local parts shop and picked up the Rubicon Express TC lowering kit.

I did a test drive after the install and reproduced the same conditions and didn't get any noticeable vibration. If anything, there's maybe a tiny vibration at just over 70, but I may have imagined that, and I don't drive 70 anyway.

Hopefully the RE kit is doing the job, but I have to say I'm not impressed with it. The plastic spacers start getting crushed before you reach the torque spec on the bolts. And the washers deform before you get the bolts to torque. I replace the washers with better hardware, but the spacers are what they are.

Not recommended, but it will do as a temporary solution.

Next up is to look at adjustable control arms to see adjusting pinion angle lets me get rid of the TC drop.