JK minor suspension lift, upgrade to adjustable shocks, add air springs (or AiROCK)

[Gary Franks]

I would like to have your comments/advice on my planned modifications to my 2008 Jeep Wrangler Unlimited Sahara 4x4. I am planning a minor suspension lift, adding air springs and upgrading to adjustable shocks.

Everything under my Jeep is stock and my wheels/tires are stock (18” wheel, 32” tire). This is my first offroad vehicle (mid-life crisis toy). I have participated in a number of offroad training classes and adventures, so I now have a better idea of what I want to do with my Jeep and what it needs to do it better.

I will not be rock-crawling. I will not be desert racing. I will be driving the Jeep on sand dunes, washboard gravel roads, washes, and all of the typical backcountry, offroad experiences (short of the Rubicon Trail). I sometimes tow a 3500# boat (not offroad). I will be towing a 1500# camping trailer offroad. I sometimes drive the Jeep with and without its hardtop and full steel doors (a big difference in the weight). I have a Gobi roof rack that is sometimes fully loaded with camping gear. I sometimes have four adults onboard, sometimes just the two of us. I will use the Jeep for on-highway adventures also, so I don’t want to sacrifice its on-highway handling and ride.

I have discovered that the Jeep will sag in the rear significantly when I am towing the boat around town (everybody flashes their high-beams at me). While this was merely annoying around town, I discovered that when towing an offroad camping trailer this sagging caused me to lose much needed clearance on the trail. On a recent adventure, loaded with 4 adults, the camping trailer, food, gear and gas for four days, the Jeep embarrassingly looked like a low-rider.

I believe that my best solution for this problem is to add adjustable air springs to maintain the proper ride height in the rear of the Jeep. I am considering a pair of either the Air-Lift or the Firestoneair bags. I have not heard a strong opinion on one brand over the other. I am considering having them installed with their own air compressor and have in-cab control or just use an external air source and manually adjust them when needed.

In all of my offroad adventures with other, more highly modified vehicles (significant lifts, huge tires, full lockers, etc.), I found that I was able to go almost everywhere they went. I found that my Achilles heel was usually clearance in the middle of my vehicle – getting high centered.

I believe that my best solution for this problem is a suspension lift. I don’t feel that I need to get bigger tires. I don’t want to lift the vehicle to the extent that I jeopardize stability when I am towing the boat on the highway. I believe that a 2” lift is the maximum. I am considering the Daystar Comfort Ride 1.75” lift. I am hoping that this, in combination with the air springs, will give me just a little more clearance to avoid high centering as often.

I have found that in a single weekend adventure, I may travel a great distance on the highway, many miles on washboard roads, a few miles of rocky washes, another few miles of technical terrain and then back through them all over again. This suggests to me that adjustable shocks would make things more comfortable and the Jeep easier to handle.

I believe that adjustable shocks is my best solution for this. I am considering the Rancho RS9000XL. I am also considering the Rancho MyRide remote control system to adjust the shocks more easily.

These are the three systems that I am considering and I would like to have your opinion or suggestions for alternatives. I never like to say that money is no object, but I will say that it is not an issue.

An additional note about the air bags and shocks. I am having an offroad camping trailer built with trailing-arm suspension and I suspect that I will want to use the same bags (to adjust for varying loads) and shocks in the trailer. The trailer is a topic for another thread someday.

I look forward to your comments. I will be making my decision very soon and I will report back here when these items are installed and give my report on the results. Thank you.

 

[tacomadave]

I have the Daystar 1.75" spacer lift, its not bad, but the "Teraflex 1.5 performance lift" is supposed to be a lot better.

I'm debating going to OME coils and shocks, but that won't be for a while.

 

[96discoXD]

You'd be hard pressed to go wrong with the OME springs and shocks, they're some of the best in the industry. You can spec the springs that you want to tailor them to the intended use of your vehicle so that you have the necessary load carrying capabilities. I will be installing either an OME or AEV lift on my JKU when the time comes. Air bags are certainly another option for a heavier load in the rear of the jeep. The important thing to bear in mind is that the JK's payload max is only around 1,000lbs including passengers so while you can improve the springs and shocks be mindful of how much gear you'll be hauling. Additionally if you have an automatic be sure to install a good trans cooler if you're going to tow/haul stuff, especially in an off road environment.

 

[Gary Franks]

...but the "Teraflex 1.5 performance lift" is supposed to be a lot better...

As I understand it, the Teraflex Performance Kit includes springs which would be unnessary if I install air springs, right? So, the Teraflex budget leveling kit is what I would use. Would that be any better than the Daystar?

You'd be hard pressed to go wrong with the OME springs and shocks, they're some of the best in the industry. You can spec the springs that you want to tailor them to the intended use of your vehicle so that you have the necessary load carrying capabilities.

But the OME system wouldn't be adjustable. I would have to install a system for either heavy loads or light loads and then I'm stuck with that configuration, right?

...the JK's payload max is only around 1,000lbs

Good point, that's one of the reasons that I'm getting an offroad trailer.

...if you have an automatic be sure to install a good trans cooler if you're going to tow/haul stuff, especially in an off road environment.

Another good point, I have a SuperChips Flashpaq that allows me to monitor transmission temperature in realtime. So far, so good. My Jeep has the factory tow package which includes different rear axle gearing. I assume that helps too.

Thank you for your input.

 

[96discoXD]

Correct, OME wouldn't be adjustable, but I don't see any reason you couldn't run a medium rear spring rate and still run airbags for when you haul more gear or tow something.
I also have the towing package on my JKU, but I don't believe being able to monitor the temp is enough. I have seen numerous people reporting high transmission temps on these when off road even without being significantly loaded. There is a reason the Rubicons come from the factory with a more robust transmission cooling system, Jeep should have included it on all of the JK's but chose not to. I will be adding a trans cooler to mine in the spring for peace of mind. You can add a B&M plate-style trans cooler for around $100-$150 including all the fittings and hose et al.

 

[Bennyhana]

Just an FYI, the Teraflex budget leveling kit(spacers) has a pointed spacer in the rear to keep the spring aligned during articulation. The point extends about 3 inches down into the spring. You wont be able to use the inside the spring airbags with these. I went with the "premium" leveling kit which has the 1.5" longer springs. I don't think they significantly boosted my cargo capacity but they are stiffer than my worn out rubicon springs so the jeep doesn't sag with my gear in it anymore.

 

[Gary Franks]

...the Rubicons come from the factory with a more robust transmission cooling system...

I didn't know that the Rubicon had a different trans cooling system than the Sahara. I couldn't find any description of the difference in my Jeep brochures from 2008 or 2010.

Nonetheless, I agree that it would be a good idea to add an auxillary transmission cooler (I like the B&M Hi-Tek model). So that I don't hijack my own thread here by starting a transmission cooler discussion, I found a good thread on the topic here.

Now I've got another project to add to my list... thanks a lot!

...the Teraflex budget leveling kit(spacers) has a pointed spacer ... You wont be able to use the inside the spring airbags with these.

Thanks for the tip.

 

[96discoXD]

No problem, I did quite a bit of research and someone on one of the JK forums mentioned that the dealer had a part number for a rubicon trans cooler. Numerous people have monitored trans temps before and after and recorded significant drops in temp. Even if it doesn't get hot enough to destroy the trans without a cooler, it will inevitably shorten the life of the trans. I looked at it as more of an ounce of prevention. I saw that you had posted over on jeepforum too, hopefully you'll get some more useful suspension advice over there too. Good luck.
Cheers!

 

[JIMBO]

:sombrero: I've got an '08 JKU Rubi with RC steel 2.5" spacers and I use the RS9000XL (adj) shocks and they are flawless, whether I'm just driving street/off-road/pulling off-road trailer-

The Rubi stock cooling system is exactly the same as the Sahara--INADEQUATE-

To get any performance out of your JKU, you'll need aftermkt aux coolers-I've gone redundant with two aux coolers and I have temp monitoring sys to keep track of the auto temps-It now rarely gets over 200°-under load



Good luck

:costumed-smiley-007:wings: JIMBO

 

[McZippie]

FWIW ...
I'd be leery of the Rancho adjustable shocks without more investigating how they would effect overall ride.

I'd lean towards a ARB/OME spring and shock 2" lift suspension system. Geared towards good on/off road ride characteristics with stock wheels.
Check out their heavy load package.

http://www.arbusa.com/uploads/PDF/accessorizeYourRig/jeepWranglerJK4door.pdf

http://www.arbusa.com/Products/Suspension-Systems/Nitrocharger-Sport-Shock-Absorbers/128.aspx

http://www.arbusa.com/Products/Suspension-Systems/Coil-Springs/33.aspx

For trailering or extra heavy loads, air bags in the rear only. Air lift or Firestone are the same air bags, just different names on them.

Stongly consider Air Lift's "Wireless Air" as the controller for the air bags. It's an easy install and works great. You can find tune the air pressure on the fly.

http://www.suspensionconnection.com/cgi-bin/suscon/72000-wireless-air.html

Disclaimer:
I have never installed or used ARB/OME shocks or springs, only know what I read. Have installed Wireless Air and endorse it.

 

[Petro]

I'd look at a 2.5" lift from Rockkrawler. Would give you a little more clearance, but more importantly, they come with progressive springs. The AEV lift also has progressive springs but at 3.5" is probably higher than you want to go. The progressive springs would certainly help with sagging while towing without having air bags

 

[Hilldweller]

I'd look at a 2.5" lift from Rockkrawler. Would give you a little more clearance, but more importantly, they come with progressive springs.

X2.
It's the best lift at a modest height you can get. Add some Bilstein shocks and forget about anything "adjustable" --- it will break offroad.

I have an '08 and tried the air springs. Been there, broke that. I tried them 3 times and they failed each time.

My camping trailer is about 1500 pounds on light weekends and closer to 2000 pounds on extended boondoggles.

And I'd regear to 4.88 gears, mount 33s on 16s with 4.5" backspacing, and run the trans cooler. The wheels with proper backspacing will help to mitigate the top-heaviness that you've induced with the roofrack and lift. Gears will motorvate you and 33s on 16s will give you much much better rubber at better prices, more clearance, and better sidewalls for airing-down.

 

[96discoXD]

X2.
mount 33s on 16s with 4.5" backspacing...33s on 16s will give you much much better rubber at better prices, more clearance, and better sidewalls for airing-down.

Good advice. I have a set of five stock 16" steel wheels I'll be running with 33" KM2's later on. I'm going to run a 255/85R16 which shouldn't require any spacers or aftermarket wheels. If he runs a 2.5 or so lift he should be able to get away a 305/70R16 with a 4.5" backspacing with no rubbing even with the sway bars disco'd. I'm just running a .75" leveling spacer in the front which is why I'm going to stick with the 255/85R16's.

I hadn't hear of that rockcrawler lift before, I'll have to take a closer look at that when the time comes.

 

[Hilldweller]

I hadn't hear of that rockcrawler lift before, I'll have to take a closer look at that when the time comes.

You'll like it. Real performance and real knowledge.

OME might have a few good parts but they don't offer a "lift kit" for the JK.

 

[McZippie]

You'll like it. Real performance and real knowledge.

OME might have a few good parts but they don't offer a "lift kit" for the JK.

??? ARB/OME suspension kits:

http://store.arbusa.com/2-Inch-Jk-4-Door-Light-Kit-P20933.aspx

http://store.arbusa.com/2-Inch-Jk-4-Door-Heavy-Kit-P20911.aspx