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3rd shock over rear axle

Gren71

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Ive got my order in for it, just waiting for it to be available. Im sure its just my imagination but i just want it :movember:
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ShadowsPapa

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The only time any such thing could do anything is if you lost traction - it could prevent wheel hop but wheel hop on a 4 link differential? Seriously? Is it that weak back there that the bushings are compressed and there's that sort of movement? Do you lose traction with these things and need to prevent wheel hop?
For the pinion to climb the ring gear, and thus wind the axle housing nose up with it, there has to be flex - something has to give.
I guess if the bushings get old and cracked and worn and you have slop in those arms, but I've never had wheel hop with my JT and I've messed around and tried to get it to spin the wheels when I take off. I can get a tiny bit of spin on a sandy intersection (which is all of them after winter in Iowa) but no wheel hop.
As far as towing - can't see how that could do a thing at all towing. You'd still have to have the housing twist, and for that, it would mean poor design, loose parts, etc.
I know guys who convert leaf spring systems to 4 link rears to get rid of the twist and wheel hop (for racing) Racers love the 4 link system similar to the JT rear.
 

CerOf

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Yeah, doesn’t make much sense.

I can spin the tires at will when traction control is off.
The diesel has lots of torque.

Even then, I’ve never had wheel hop.

If any JT gets it, it would be a diesel. But still, the 4-link upper and lowers should prevent any.
 

81Mojave

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I get wheel hop in my 6spd Mojave in sand when starting from a stop… it’s bad enough where I have had to go into 4WD to get moving….
 

JT1

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I get wheel hop in my 6spd Mojave in sand when starting from a stop… it’s bad enough where I have had to go into 4WD to get moving….
That's really interesting!
I've had mine out in loose river silt, but its never more than an inch or 2 deep. When I lifted the truck, I left mine off and haven't noticed a difference except its easier to modulate the clutch in 1st gear.
 

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jmsreynolds

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I have a 21 Rubicon Auto. I went out in the snow for the first time yesterday. We had about 8 inches. It didn't matter if I was in 2wd, 4wd, lockers on or off, light or heavy on the pedal, the rear was hopping like crazy vibrating and shaking the whole truck, I thought for sure it would break something. Really hoping stiffer springs and shocks when I lift it will fix the issue. I feel like the added shock on the diff would interfere with a lift and articulation without having to really modify the bracketry.
 

ShadowsPapa

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I have a 21 Rubicon Auto. I went out in the snow for the first time yesterday. We had about 8 inches. It didn't matter if I was in 2wd, 4wd, lockers on or off, light or heavy on the pedal, the rear was hopping like crazy vibrating and shaking the whole truck, I thought for sure it would break something. Really hoping stiffer springs and shocks when I lift it will fix the issue. I feel like the added shock on the diff would interfere with a lift and articulation without having to really modify the bracketry.
Lift springs will be taller not necessarily stiffer. Normally such things as lifts make things worse because of longer and extended parts.
If the lift includes different bushings maybe but lift springs shouldnt be stiffer and shocks don't usually impact axle wind-up.
 

jeepin48

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I have a 21 Rubicon Auto. I went out in the snow for the first time yesterday. We had about 8 inches. It didn't matter if I was in 2wd, 4wd, lockers on or off, light or heavy on the pedal, the rear was hopping like crazy vibrating and shaking the whole truck, I thought for sure it would break something. Really hoping stiffer springs and shocks when I lift it will fix the issue. I feel like the added shock on the diff would interfere with a lift and articulation without having to really modify the bracketry.
Power hop is exactly what that center diff shock is for. If your rear axle ends up hopping on a surface with enough traction then you will blow out your rear end gears.

Because it is located in center of the differential it should not affect the articulation much if at all for stock height.

I have notice hop while starting from a stop with my diesel on sand.

Can anyone confirm that it actually helps?
 
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ShadowsPapa

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Power hop is exactly what that center diff shock is for. If your rear axle ends up hopping on a surface with enough traction then you will blow out your rear end gears.

Because it is located in center of the differential it should not affect the articulation much if at all for stock height.

I have notice hop while starting from a stop with my diesel.

Can anyone confirm that it actually helps?
It's often worse with a diesel due to the low end torque advantage those engines have. And yes, axles can break, teeth can be chipped or broken if you spin, hop and hit sudden traction.
I've seen guys bust axles when high torque breaks tires loose and then they gain sudden traction - SNAP.

On muscle cars, off-set shocks help some. There's a shock mounted lower end to the front side of one axle angled forward to the frame and the other shock is mounted to the rear side of the other axle, angled rearward to the frame. It helps prevent axle housing twisting and wheel hop.
 

brianinca

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I had serious wheel hop on my old Ranger (rear leafs) and throwing away almost brand new factory shocks for MUCH better Rancho 9000's solved the problem completely.

Kind of shocking how important dampers are. Ba-dum-tiss!

It's often worse with a diesel due to the low end torque advantage those engines have. And yes, axles can break, teeth can be chipped or broken if you spin, hop and hit sudden traction.
I've seen guys bust axles when high torque breaks tires loose and then they gain sudden traction - SNAP.

On muscle cars, off-set shocks help some. There's a shock mounted lower end to the front side of one axle angled forward to the frame and the other shock is mounted to the rear side of the other axle, angled rearward to the frame. It helps prevent axle housing twisting and wheel hop.
 

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MPMB

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As some have said, the damper is meant to control the rotation of the rear end housing (top goes back, pinion goes up, parts damaged, power is lost, etc.) to help prevent wheel hop.

In my racing days, we ran a 3rd link with a 1500# spring to help make a smoother corner apex and exit under power.

Some racers have the spring for power wrap, and add a damper that is mounted the opposite angle (say 3rd link is statically angled down 15*, the damper is angled up 15*) to absorb the forces as the rear end unwraps itself. This damper is usually a heavy compression, no rebound damper.

There are geometry forces also at work, so when you move the angles of suspension geometry around, the loads shift around. Minimizing those changes, which is what the damper is doing, help maintain the designed geometry.
 

ShadowsPapa

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I had serious wheel hop on my old Ranger (rear leafs) and throwing away almost brand new factory shocks for MUCH better Rancho 9000's solved the problem completely.

Kind of shocking how important dampers are. Ba-dum-tiss!
HAHA - ready for the stage and stand-up I see! OK, Howie, LOL

Leaf springs are horrible for wheel hop and axle "wrap" or wind-up. They generally have shocks more staggered and in those cases, it's really important to have good shocks.
Not saying that they can't help - given the right type of configuration they can mean everything.
The pinion wants to climb the ring gear under heavy torque - so the differential housing noses up until the leaf springs (or bushings) have had all they can take for the given torque and something lets loose - the wheels slip and the spring (or bushings) unwind and the pinion noses down - reaches the end and the wheels grab and the pinion climbs again........
My performance cars have staggered shocks but I'm still putting more power to the rear than it's engineered to handle - so in the 70 I sold I rebuilt the torque links which prevented spring wrap and lifted the rear of the car upon heavy acceleration forcing the wheels down more.
On my 73 it took CalTracs to settle things down - when the axle tries to wind up, the transfer force forward. Geometry........

I can't recall how the shocks are canted on a Ranger......... but leaf springs are horrible for axle twisting and wheel hop.
 

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With the 5 link of the gladiator, wheel hop shouldn’t be a big deal. I’ve never experienced it that I’m aware, even with 400+tq
 

RodRecket

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Power hop is exactly what that center diff shock is for. If your rear axle ends up hopping on a surface with enough traction then you will blow out your rear end gears.

Because it is located in center of the differential it should not affect the articulation much if at all for stock height.

I have notice hop while starting from a stop with my diesel on sand.

Can anyone confirm that it actually helps?
I can't speak to wheel hop without it but my sport s (6MT) came with it and I have never experienced wheel hop. Maybe @Gren71 has gotten the part in and has some input.
 

Gren71

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I can't speak to wheel hop without it but my sport s (6MT) came with it and I have never experienced wheel hop. Maybe @Gren71 has gotten the part in and has some input.
SOOOOOOO funny story...I did get the part but when going to install the bracket I snapped off a bolt in the top of my rear diff. So im pretty much never getting this thing put in haha. I can, and will, sell and ship the shock to anyone who wants to try their luck.
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