Rock Hard Rancho

[WAC51]

I have a 1981 CJ7 (AMC 258 i6 / 4.2l engine).

The jeep has been fitted with a Rancho “add a leaf” lift kit and Rancho RS5000 Shocks. I think that it may also fitted with reversed shackles, I am not 100% sure of this. The body height is 23” from the ground.

It is also running twin Rancho steering stabilisers and I think that the pitman arm has been dropped (again not sure).

The Jeep is running on Mickey Thompson 31 X 15.50 / 15 Baja Belted tyres.

My problem is that there is absolutely no movement in the suspension, it is rock hard. (I weigh 190lbs and when I bounce on the rear bumper the Jeep moves about ½ inch). The Jeep is dangerous to drive at 40mph. We have very poor tarmac surfaces here and the Jeep feels as if it is going to jump off the road at any time.

I need to improve the ride quality and I think that dampening out the poor road surface is the priority.

Can you please give me some advice as to whether I should change the shocks or springs or both, and if so what I should change to (I want to keep the ride height) and also what could be done to sure up the steering.

Any help is much appreciated.

Thanks

 

[IOPort51]

I have had a total of one set of rancho springs and shocks and that set, on a FSJ, rode like it had no springs or shocks. Pretty rough.
My recommendation is a set of skyjacker or OME springs and shocks.
This is MHO and I am sure there will be more to come.
:ww:from the Republic of Texas.

 

[BusaDave9]

Welcome to the site!!!!
:ww:

I think that it may also fitted with reversed shackles, I am not 100% sure of this.

Normally the front shackles are at the front of the front springs. A shackle reversal entails moving the shackles to the rear of the front springs.

I think that the pitman arm has been dropped (again not sure).

A dropped pitman arm looks like this:

Normally a CJ pitman arm doesn't have much bend to it. OEM looks more like this:

Now on to your rough ride. To soften up your ride I would replace the springs. It doesn't sound like dampening is your problem.
Many suspension manufactures make CJ springs. Look for some softer springs but don't set your expectations too high. A CJ will never ride as well as most other passenger cars especially if you have a lift.

 

[73CJ]

Howdy!

Take some pics of the components - pitman arm, shackle reverse.

That would really help us figure it out.

Should be looking at 1-2" lift. Sounds like a real high spring rate, 350 - 500#/inch. Measure the height of the bumper. Load the rear end up with several buddies. Remeasure and divide by 2 will give you the spring rate. Stock is around 200#/INCH.

So what part of Ireland are you in?

 

[WAC51]

Thanks Guys,

I will get some pictures later and load them up. The Pitman arm is dropped as it is the same as the first picture.

I will get some decent pictures of the shackles.

I am in the village of Killaloe in County Clare, right on the shores of Lough Derg. Not a nicer place in the world when the sun shines, unfortunatly doesn't shine that often!

 

[WAC51]

Hi Guys,

Had my brother drive the Jeep back to our workshop (about 4 miles from my house).

As I was following it the Jeep looked to be crabbing really bad and moving around on road, yet when we got into the yard and measured up it all seemed to be square.

I am going to put it on the lift over the weekend, it looks like there is something loose or broken underneath.

Any common faults/breaks that I should be looking for?

Thanks

 

[73CJ]

Hi Guys,

Had my brother drive the Jeep back to our workshop (about 4 miles from my house).

As I was following it the Jeep looked to be crabbing really bad and moving around on road, yet when we got into the yard and measured up it all seemed to be square.

I am going to put it on the lift over the weekend, it looks like there is something loose or broken underneath.

Any common faults/breaks that I should be looking for?

Thanks

Look for worn spring bushings, broken spring mounts on the frame, loose/ worn shackle bolts. Loose steering box mounts.

Crank the wheel back and forth and watch the front spring and frame movement.

Loose U-bolts on the spring and axle. Loose wheel bearings.