Okay is a shackle reversal really worth the money?

CJman77 · 02-04-2009, 04:37 PM

Okay I am about to buy a MORE shackle reversal to mount on my 77 CJ7. I have a 4 inch skyjacker CJ kit with stock size shackles. I will be mainly driving 80% of the time on Pavement. Is it worth it for me to go with the shackle reversal? Will it make a huge difference?

If yes how do I control the nose dive I have heard is associated with SRS?

**BESRK** · 02-04-2009, 05:06 PM

I ran a SRS on my old CJ5 and never really notice any excess "nose dive" during hard braking.. not any more than normal anyways. The Jeep did track nicely down the road and I didn't have to worry about jamming my shackles into the dirt on big dropoffs.
Having said that, I think a properly setup "factory" setup (shackle up front), drives just about as well. It drives well enough for me not to bother with converting my current CJ5... yet.
One thing I did notice with my old SRS was the amount of front driveshaft "slip" travel doubled. You'll want to run a "long travel" (or at least longer travel) front driveshaft to avoid bottoming the splines on hard compression.

CJman77 · 02-04-2009, 06:16 PM

Quote:

Originally Posted by BESRK

I ran a SRS on my old CJ5 and never really notice any excess "nose dive" during hard braking.. not any more than normal anyways. The Jeep did track nicely down the road and I didn't have to worry about jamming my shackles into the dirt on big dropoffs.
Having said that, I think a properly setup "factory" setup (shackle up front), drives just about as well. It drives well enough for me not to bother with converting my current CJ5... yet.
One thing I did notice with my old SRS was the amount of front driveshaft "slip" travel doubled. You'll want to run a "long travel" (or at least longer travel) front driveshaft to avoid bottoming the splines on hard compression.

So what would constitute a "properly setup factory setup"? I am curious.

Bard · 02-04-2009, 06:32 PM

Quote:

Originally Posted by CJman77

So what would constitute a "properly setup factory setup"? I am curious.

Since you have already altered the factory with a 4" lift, nothing is factory, what he was referring to is keeping it the same shackle up front like you have it.

I agree with what Eddie said. My question is which way does it nose dive and what is the crown of the road when this occurs? Do you run a sway bar set up? I can't remember if a 77 had them. What is causing the nose dive? bad rotor, wheel bearing, rim bent, bad shocks, etc. Lots of things can cause it to dive.

CJman77 · 02-04-2009, 08:50 PM

Quote:

Originally Posted by Bard

Since you have already altered the factory with a 4" lift, nothing is factory, what he was referring to is keeping it the same shackle up front like you have it.

I agree with what Eddie said. My question is which way does it nose dive and what is the crown of the road when this occurs? Do you run a sway bar set up? I can't remember if a 77 had them. What is causing the nose dive? bad rotor, wheel bearing, rim bent, bad shocks, etc. Lots of things can cause it to dive.

I dont know if it nose dives. I was told that they tend to nose dive in general when done with a SRS. I am curious if there are things you can do to curtail this.

CJman77 · 02-08-2009, 10:16 PM

Quote:

Originally Posted by CJman77

I dont know if it nose dives. I was told that they tend to nose dive in general when done with a SRS. I am curious if there are things you can do to curtail this.

Anyone have any other thoughts?

jackstercj8 · 02-09-2009, 09:17 AM

Just a thought, I noticed our newer semi's at work are rev shackled, must be something to it.

**JeepHammer** · 02-09-2009, 10:25 AM

Quote:

Originally Posted by CJman77

Okay I am about to buy a MORE shackle reversal to mount on my 77 CJ7. I have a 4 inch skyjacker CJ kit with stock size shackles. I will be mainly driving 80% of the time on Pavement. Is it worth it for me to go with the shackle reversal? Will it make a huge difference?

I did shackle reversal on everything for quite a while...
And it worked for me.
Better road manners, smoother ride, not as much 'Dive' in the front when I applied brakes,
And it crawled over obstructions better.

Didn't buy a 'Kit', just bought another frame mount and attached it in the front,
(Some times, you will need to make an EXTENSION to lower the spring mount to keep your CASTER angle correct)

I also add a tubing cross member in the front between the spring mounts I install.
Cross member not 'Necessary', but helps stiffen up the front end, and the steering feels a lot more 'Solid' afterwards...
And it's nothing but a piece of thick wall tubing, so it's REAL easy!

Then put a piece of tubing through the frame in the rear, welded it in with support gussets, for the shackle bushing.
Just a piece of 1" internal diameter tubing for the bushings I was using at the time... Nothing to it!
Made the shackles out of 1/4" thick material and was done.

You REALLY NEED to take a Caster Angle reading before you do the shackle reversal,
And if you have large tires or lift, add some Caster to the mix...
This will make your vehicle steer MUCH better...
Won't climb the Tire Ruts in the pavement lanes nearly as much,
Centers like it's supposed to, ect.

Since you are moving the spring mounts, you can move the front axle FORWARD just a bit to lengthen wheel base,
AND that will give the drive shaft some breathing room!
(Don't move too far forward, or you will bind up the steering linkage!)

Remember, once you do a shackle reversal, the drive shaft COMPRESSES instead of Expands like it did with shackles in the front, so some people will 'Bottom Out' the drive shaft when compressing the suspension...
Not likely at all with a lift, but possible with stock spring...

Quote:

If yes how do I control the nose dive I have heard is associated with SRS?

I didnt' get 'Nose Dive', and actually the Breaking Dive was lessened when I did the Reversal...

You have to watch what angle your shackles are at at 'Ride Weight/Height'...
If the shackles are 'FOLDING UP', the nose will dive.

If the shackles are 'Standing Up' when the weight transfers to front during breaking, there won't be any 'Dive'.
Since YOU are the one installing the Rear Shackle Pivot Point, you can adjust it anywhere you want it!

Put sandbags in the drivers seat, put a wood block between frame and spring EYE where shackle should be (rear), and let the jeep down on the wood block so it's supporting it's own weight.

Figure out where the upper shackle pivot needs to be to make the shackle 'Stand Up' when more weight is applied to the front (Spring will get LONGER and move BACKWARD) so you want your rear mount BEHIND the spring Eye for highway use...
So when you brake, the spring gets longer with the extra weight,
The shackle will add HEIGHT between frame and spring as the spring gets longer.

If you were WHEELING a lot,
You would want the upper shackle pivot point STRAIGHT UP or FORWARD of the spring eye...
That way, the suspension can DROOP a bunch and still compress keeping the shackle in it's proper plane of motion.

JoonHoss · 02-09-2009, 11:50 AM

I did a SRS/CJ7 4" lift springs on my '72 Commando- I loved it, and never had a problem.

seems like everytime it's mentioned here, a bunch of people who have heard of the problems complain, but I never noticed anything I felt worth complaining over.

hth

Hoss

CJman77 · 02-09-2009, 12:14 PM

Quote:

Originally Posted by JoonHoss

I did a SRS/CJ7 4" lift springs on my '72 Commando- I loved it, and never had a problem.

seems like everytime it's mentioned here, a bunch of people who have heard of the problems complain, but I never noticed anything I felt worth complaining over.

hth

Hoss

Ok ok cool sounds like I will be doing a SRS!

atomicflatulenc · 02-09-2009, 07:11 PM

How did you keep the ride height level? I was thnking of doing it, but don't you get an extra Inch up front?

CJman77 · 02-09-2009, 07:40 PM

Quote:

Originally Posted by atomicflatulenc

How did you keep the ride height level? I was thnking of doing it, but don't you get an extra Inch up front?

if you get a M.O.R.E. offroad kit you can get one that changes the front springs rear leaf mount to adjust the lift so it doesn't add any lift to the jeep. You just cut it the old one off. Figure out where on the frame you drill a hole, weld in a steel sleeve and the kit comes with a shackle for attaching straight to the frame hole you made. Sound like it will be a fun time. Looking forward to it. LOL

rmc429 · 02-10-2009, 07:15 PM

http://rthompson.us/2007/12/03/diy-jeep-cj-7-shackle-reversal/

Has anybody done it like this? Just wondering how that would work. Seems like it would be really easy but not sure what it would do to caster.

**BESRK** · 02-10-2009, 07:23 PM

Quote:

Originally Posted by CJman77

So what would constitute a "properly setup factory setup"? I am curious.

Maybe I chose my words poorly. I was referring to the stock style setup with the shackle up front. By "properly setup" I was referring to things like, quality springs, shocks that work well with those springs, bushings in good shape, proper caster...etc.

My current setup is Rubicon Express 4" YJ Standard springs with poly bushings. Rancho RS9000 shocks (12.5" travel). Homemade 3/8" thick 4" long shackles. High steer on the Dana 44 (only because I already had the setup off an old project). It's all "tight" rides well and flexes really well for a CJ5 on leaf springs.

babytank31 · 02-10-2009, 08:55 PM

I have a 78 cj5 with a warior kit that I installed and feel the same way about it as Besrk does with his, no real difference in anything. Mine did raise front about an inch, removed rear spring shackle hangers from frame. Used them as a templet to drill the two holes in a piece of 2x3/4 flat bar as a spacer then welded to frame and reinstalled with longer bolts.