Rear suspension too soft on Mojave, squats

[KurtP]

Dramatic? No.

Springs only with that load? No.

With the load he's talking fully loaded, he needs springs and shocks plus the air bags mentioned.

If not, it won't be long before a rear shock will blow. Top loading the bed puts a LOT more stress on the rear suspension than hauling or towing.

What are you basing any of that on?

Why are new springs and airbags required to carry 300lb?

Why does carrying a 300lb load mean the shocks will blow?

I think i would humbly suggest you dont actually know. Unless youve shock dyno’d the shocks, you dont know what the valving rate is or what the spring rate range is. The spring rate required to adequately carry 3-500lb with minimal squat is not that high. If the spring doesnt cause the shock to bounce, then its not being over driven.

As i type this, im pumping gas into a Mojave with 300lb in the bed and stiffer springs. It drives and rides awesome.

Sponsored

 

[kevman65]

What are you basing any of that on?

Why are new springs and airbags required to carry 300lb?

Why does carrying a 300lb load mean the shocks will blow?

I think i would humbly suggest you dont actually know. Unless youve shock dyno’d the shocks, you dont know what the valving rate is or what the spring rate range is. The spring rate required to adequately carry 3-500lb with minimal squat is not that high. If the spring doesnt cause the shock to bounce, then its not being over driven.

As i type this, im pumping gas into a Mojave with 300lb in the bed and stiffer springs. It drives and rides awesome.

What I'm basing it on is the fact the Mojave has a softer suspension than the Rubi or Overland.
People with Overland's are already stating that they are bottoming out, there's a few threads about it.

The OEM shocks will work, for awhile, but by top loading and causing more sway and deeper cycles on the shocks, they are going to fail much faster. Say what you want, but NONE of the OEM shocks are designed for the work cycles that true overlanding will put them through.
Most guys that lift their Overland's end up putting better shocks on to accompany the lift. By not upgrading shocks that are designed to be a softer, faster ride, one is asking for trouble.

Just because my opinion doesn't agree with what you think is right doesn't mean I don't know what I'm talking about.

Springs carry the load, shocks control the springs. Upgrade one and not the other is a recipe for bad things.

 

[KurtP]

What I'm basing it on is the fact the Mojave has a softer suspension than the Rubi or Overland.
People with Overland's are already stating that they are bottoming out, there's a few threads about it.

The OEM shocks will work, for awhile, but by top loading and causing more sway and deeper cycles on the shocks, they are going to fail much faster. Say what you want, but NONE of the OEM shocks are designed for the work cycles that true overlanding will put them through.
Most guys that lift their Overland's end up putting better shocks on to accompany the lift. By not upgrading shocks that are designed to be a softer, faster ride, one is asking for trouble.

Just because my opinion doesn't agree with what you think is right doesn't mean I don't know what I'm talking about.

Springs carry the load, shocks control the springs. Upgrade one and not the other is a recipe for bad things.

Im not trying to be a dick, but I guess My point is you actually dont know what youre talking about. Have you driven a stiffer sprung mojave? I have. I have one, with stiffer springs, in my driveway. Ironically with 300lb in the bed.

Have you shock dyno’d the shocks to know what their spring rate limit is? Do you know what the stock spring rate is? What spring rate increase would be required to reduce a 500lb squat to 1” or less?

If the answer to all of those questions is “no” and “i dont know” and you’re simply going on the fact the rear spring rate is softer per Jeep advertising as your only data point, then you have no idea what youre talking about.

Random ass guessing based on some post you read about a truck you dont have doesnt really get the answers the OP is looking for. Opinions are great. But they need supporting data.

 

[kevman65]

No, I am basing my knowledge on racing motorcycles for over 30 years and spending tons of money to specially tune shocks for specific loads and the fact that the same mathematics and physics apply.

It's great that your set up feels great to you.

But it is not the optimum set up to throw just stiffer springs in and load a fixed load 4 to 5 feet above the bed of the truck and expect the stock, soft ass shocks to perform safely.

Enjoy your ride. Don't throw labels at people you don't know.

 

[GladiatorAdventureBound]

It's a really stiff ride...

I don’t think so at all. What are you basing that on?

 

[KurtP]

No, I am basing my knowledge on racing motorcycles for over 30 years and spending tons of money to specially tune shocks for specific loads and the fact that the same mathematics and physics apply.

It's great that your set up feels great to you.

But it is not the optimum set up to throw just stiffer springs in and load a fixed load 4 to 5 feet above the bed of the truck and expect the stock, soft ass shocks to perform safely.

Enjoy your ride. Don't throw labels at people you don't know.

Arguments of authority dont work. Arguments of merit do. Im not labeling you, im asking for actual data points, pointing out where youre wrong, and asking you to reconsider.

Ive built trucks as a part of my living. Ive worked at race shops. Ive worked for a race team. Ive upfit consumer vehicles into heavy trucks that have served in the harshest conditions imaginable on every continent sans Antarctica.

If the shock is not being over driven by the spring, it will not fail prematurely. The fact is you have zero data points to know when the shock is being over driven. If youve done half of what you claim you have, youll know how to calculate a spring rate. When you do, youll see the required rate for his use is not that high and will be well within the capabilities of the shock.

At any rate, OP can decide what path he is taking based on whats been presented.

 

[MarcusB]

Thanks for the opinions. Just what i needed. I might start with the airbags to keep the Mojave suspension as close to factory as possible. ??

 

[KurtP]

Thanks for the opinions. Just what i needed. I might start with the airbags to keep the Mojave suspension as close to factory as possible. ??

At this point it is difficult to get stiffer springs without lifting. There is a spring rate chart here on the forum somewhere, so a small bump to a rubicon or max tow spring might work.

Conversely; those airbag systems when properly installed and using mechanical hoses not electronics work really well and let you vary the pressure as your load requirements fluctuate.

If you decide to spacer loft the rear, you can take the shocks out of their neutral position, but dont go over it by much more than an inch.

Edit: ie if you put a spacer on the spring without an extension on the shock, dont vary it by much more than an inch.

 

[Sazabi19]

I don’t think so at all. What are you basing that on?

My Sport S with Max Tow...

 

[KurtP]

Guys. Guys.

250mi trip...3 occupants. 400lbs of cargo. Stiffer springs on my Mojave shocks. It rode and drove great; didnt bounce, and the shocks didnt blow.

 

[Sazabi19]

I guess I should mention I usually drive unloaded, by myself.

 

[Mtpisgah]

Guys. Guys.

250mi trip...3 occupants. 400lbs of cargo. Stiffer springs on my Mojave shocks. It rode and drove great; didnt bounce, and the shocks didnt blow.

That is the kind of ride I want, but I do not want to lift, stock shocks or not.

 

[KurtP]

That is the kind of ride I want, but I do not want to lift, stock shocks or not.

I get it entirely. Options:

1- spacer the rear slightly to offset your load
Or
2- use airbag helper springs to adjust to your load

And:

Add front lower control arms and get your caster out to 6°-6.5°; and set your toe-in to the higher end of spec.

 

[Mtpisgah]

I get it entirely. Options:

1- spacer the rear slightly to offset your load
Or
2- use airbag helper springs to adjust to your load

And:

Add front lower control arms and get your caster out to 6°-6.5°; and set your toe-in to the higher end of spec.

I am looking into airbags until a stiffer spring is available Seems like a low cost temporary solution.

I need to do some research because I honestly have no idea what you mean about the control arms and caster. In my 35 years of driving, I have never modified a vehicle like I will this one. Heck, I have only put aftermarket wheels on one vehicle; my 1972 Datsun pickup.

Everything considered, I spent $54k out the door on this truck and am putting another $20k+ into the bumpers, winch, compressor, AluCab canopy camper, and other myriad items, so I really do not care if I have to spend a bit more on the suspension. I want it right. I have read a lot of your posts and you know your stuff so I value your opinion. I will keep researching.

edit: I do not want to lift because I am 5’-4”. I will got to 35” tires but probably not any bigger.

 

[KurtP]

I am looking into airbags until a stiffer spring is available Seems like a low cost temporary solution.

I need to do some research because I honestly have no idea what you mean about the control arms and caster. In my 35 years of driving, I have never modified a vehicle like I will this one. Heck, I have only put aftermarket wheels on one vehicle; my 1972 Datsun pickup.

Everything considered, I spent $54k out the door on this truck and am putting another $20k+ into the bumpers, winch, compressor, AluCab canopy camper, and other myriad items, so I really do not care if I have to spend a bit more on the suspension. I want it right. I have read a lot of your posts and you know your stuff so I value your opinion. I will keep researching.

edit: I do not want to lift because I am 5’-4”. I will got to 35” tires but probably not any bigger.

No worries man, i get it.

So, caster is how far back the steering knuckles are rotated back. Consider for visualization the extremes of the range as straight up and down; to a stretched out chopper bike.

Up and down quickest steering; chopper most stable at speed. It has become general consensus that stock caster degree is too close to up and down for quick steering on trail; but at the expense of an incredible lack of steering stability. By pushing it out a degree-degree and a half shows incredible gains in stability with no appreciable loss of quick steering when you need it; although it will weight the steering slightly.

The gains in highway stability are real.

Sooner or later stiffer springs will be available; although if youre constantly laden with a couple hundred pounds, I dont think youd find max tow springs to be harsh.

Sponsored