PDA

View Full Version : Still considering longer front shackles on my SIII 109"



bullstanky
03-06-2013, 11:47 AM
Ever since I swapped the stock springs out for parabolics in my SIII 109" 3-door, my Rover has been about 1-2" taller in the rear than in the front. This is likely because I chose the 4 leaf heavy duty parabolics for the rear which provided more lift than in the front. I only chose the 4 leaf springs cause they were labeled as heavy duty...I couldn't resist.

Initially the extra lift in the rear caused my rear drive shaft to clunk inside of the rear crossmember. With new engine and transmission mounts and a new shaft, this was eliminated.

My rover is going under the knife pretty soon--the front crossmember is rusted out and the steering unit is caput, so my shop is going to cut out the front horn and weld in a replacement that I've found, and then the whole steering system (hopefully with the exception of the steering column) will be rebuilt--new steering unit, all new tie rod ends and new damper.

While this work is being done and the front end is out, I figure it is a good time to try and gain an inch or so of ride height in the front to try and level my rover out. I've read of the many potential issues of adding longer 1-ton military shackles to the rear of the front springs--pushing the front drive unit down and forward & messing up the geometry, which can bind or cause wear to u-joints and pinions or cause the shaft to hit the crossmember, and which can only be eliminated with shimming. The option to avoid these problems is to modify the front spring hangers to drop the front spring about an inch so that the spring remains level and geometry unchanged.

It seems like I'm in the perfect place to go ahead and have my shop modify the front spring hangers on my new replacement front horn (once it has been welded in) to compensate for the longer 1-ton shackles being added to the rear of the front springs.

So here is the question--should I have them hack and weld and fab the front spring hangers on the new horn to get the desired leveling of the spring, or can I have them simply fab (or repurpose/modify the shorter shackles that I'll be replacing) shackles for the front of the springs to level them out?

The other option is to remove the 4 leaf hd rear parabolics and replace them with the regular 3 leaf ones, hoping that brings the rear down some, but since I'm already having my shop rebuild the front end, and already have the 4 leafs installed and ironed out in the rear, it would seem counter productive.

What do you fellas think?

TeriAnn
03-06-2013, 09:48 PM
Setting the front suspension up to raise the suspension & leaving the rear stock? What do you do when the rear parabolics wear out?

If you want to add an inch height in the front get a set of 109 military extended shackles for the front and add a 6 degree wedge between the axle housing and the front spring to move the kingpin angle back to where it is supposed to be.

If you can find 109 military front spring brackets, install them both front and rear. These brackets come with 2 mounting holes. The one closest to the frame is for use with civilian shackles. The lower one is for use with military long shackles. You could use the lower mounting hole AND extended shackles on the front & civilian on the rear until the rear springs wear out. The put the right springs under your truck and use the same shackles front & rear.

I really think you should swap out the rear springs & do things right.

For leaf springs "heavy duty" means they are designed to carry more weight, not that they are more rugged. The weight of the truck does not compress the springs as much on heavy duty springs so the vehicle sits higher and the ride is stiffer. If you are over sprung the springs will not flex like they would with the weight they were designed to carry. Your 4 leaf springs will give you a stiffer ride than the correct rear springs.

Don't feel alone you are not the first nor the last to make that mistake. You can ask the people you purchased the springs from if you can safely remove a leaf

o2batsea
03-07-2013, 05:33 AM
To my mind, the 4 leaf parabolics are just too much. Unless you regularly haul around depleted uranium or big block Ford engines, you really don't need them. There are pretty stiff. I would take out a leaf. I was going to do that on mine, but alas never got to it.
Even so I don't think that removing a spring will lower the back at all. You really need the longer shackles. Don't extend the frame horns. You can make custom shackles that will set up the truck level, but I think you want a little bit of rake for appearance's sake, cuz when you load it up it will sit too low in the rear.
For the front, if you are going to the trouble of rebuilding the whole mess, I highly recommend that you convert to power steering. On a 109 it is almost mandatory. TeriAnn's pages have just about all the info you need. If I were doing it all again I would use a P38 steering box. It will be outboard of the frame which is a real handy place to have it. Mine currently has the RRC/D1 box and I am thinking of pulling it out in favor of the P38 one so my intercooler and radiator fit better.

bullstanky
03-07-2013, 02:57 PM
I really think you should swap out the rear springs & do things right.

For leaf springs "heavy duty" means they are designed to carry more weight, not that they are more rugged. The weight of the truck does not compress the springs as much on heavy duty springs so the vehicle sits higher and the ride is stiffer. If you are over sprung the springs will not flex like they would with the weight they were designed to carry. Your 4 leaf springs will give you a stiffer ride than the correct rear springs.

Don't feel alone you are not the first nor the last to make that mistake. You can ask the people you purchased the springs from if you can safely remove a leaf

You're right--the correct thing to do is swap out 3 leaf rear springs for the 4 leaf H-D ones currently installed. In retrospect, I wish the folks who sold me the springs (not our host) would have recommended the 3 leaf springs when I ordered, or when I informed them of my ride height issue, rather than offering me the new rear dive shaft and engine/trans mounts that cured the rubbing of the drive shaft in the crossmember, but left me with too much spring, would have offered to swap for the 3 leaf ones. For the cost of what I paid to put the new engine/trans mounts and drive shaft in (albeit, that needed replacing anyhow) I could have put the new springs in and been set. But you live and you learn :)

bullstanky
03-07-2013, 02:59 PM
So should I just remove a leaf (how is this done?) or buy a new $400 set of 3 leaf springs and try to sell the ones I have?

busboy
03-07-2013, 03:02 PM
Look for someone that wants to trade a 3 for a 4.

SalemRover
03-08-2013, 03:48 PM
I put parabolics on a military 109 rover (3 rear / 2 Front). Mounting to the military holes and shackles caused the rear propshaft to strike the frame on articulation. I cannot recall if the front had issues (doubt it). I run the civilian shackles and mounts now. If you are not comfortable removing a leaf find a spring shop and ask them to do it. My fronts sagged after 7 years and I had new super heavy duty 2 leafs made up at a spring shop for 75$ a whack.

Jason

o2batsea
03-08-2013, 05:55 PM
I had new super heavy duty 2 leafs made up at a spring shop for 75$ a whack.

This

bullstanky
03-09-2013, 08:51 AM
I put parabolics on a military 109 rover (3 rear / 2 Front). Mounting to the military holes and shackles caused the rear propshaft to strike the frame on articulation. I cannot recall if the front had issues (doubt it). I run the civilian shackles and mounts now. If you are not comfortable removing a leaf find a spring shop and ask them to do it. My fronts sagged after 7 years and I had new super heavy duty 2 leafs made up at a spring shop for 75$ a whack.

Jason

Which of the 4 leaves do you remove ? Just cut it out?

SalemRover
03-09-2013, 08:14 PM
Which of the 4 leaves do you remove ? Just cut it out?

Honestly couldnt tell ya. That is a great question for the people that sold you the springs.

Jason

bullstanky
03-11-2013, 09:45 AM
After much consideration, it seems like there's a right way, a wrong way, and then there's the way I'm going to do it.

Swapping out the four leaf springs for a 3 leaf pair seems like the right way. But would cost the most and leave me with an unneeded pair of springs to sell.

Cutting a leaf out of my four leaf springs (seeing as how I know nothing about how this is done or how it would affect the spring) seems like the wrong way, because I might spend a bunch of time just to ruin my springs, leaving me with one pair that is shot and needing to buy replacement 3 leaf springs.

Which brings be back to my initial plan of adding military shackles to the rear of the front spring and custom shackles to the front of the spring. All I have to buy is 4 military shackle plates (I have 2 sets of civilian plates I can customize and repurpose for the front of the springs) and hook it up. If/when either the front or rear springs end up sagging and I have to replace them, I can get the correct springs then and just remove my front shackle job.

It just seems like the shackle work is cheap, easy and reversible, and if it doesn't work it leaves me buying the new springs I probably needed all along anyway, and if it does work then I'm good to go until it's time for new springs.

o2batsea
03-11-2013, 10:12 AM
Shackles are nothing more than 1/4 plate with a threaded hole on one side. The longer ones I used to have had a bar welded in the middle to keep them in plane. You can have them made locally.

I Leak Oil
03-11-2013, 10:52 AM
After much consideration, it seems like there's a right way, a wrong way, and then there's the way I'm going to do it.

I was wondering how long this would go on. If I had to do work on the front of the frame anyway I'd do the same thing and you didn't say you were unhappy with the way the 4 leafers work or ride.

When reworking the front spring mounts I'd just suggest to keep the regular spring positon in addition to the new location in case you ever do go back to regular shackles. Only other things you might consider would be to extend your bump stops, brake lines and notch the engine cross member for the drive shaft.

jac04
03-11-2013, 10:57 AM
Which brings be back to my initial plan of adding military shackles to the rear of the front spring and custom shackles to the front of the spring.
You want to have a shackle located at both the front and back of the front springs? If so, that won't work. You need a fixed mounting point at the front of the spring. Maybe I'm not understanding exactly what it is you want to do at the front of the springs.

I Leak Oil
03-11-2013, 12:50 PM
Based on the original post I think it's just a misuse of nomeclature vs. his actual understanding of what he wants to do at the front of the spring.

Stolidog
03-11-2013, 10:08 PM
If your redoing the front horns and are thinking about playing around with your hangers put on a pair of jeep yj springs. There not as long as the rear springs that some people put up front that seem to stick way out in font of the bumper but land just under. They still are about 10" longer than the stock rover springs and give you a great ride. I put in old man EMU 2 1/2 lift springs and gave me about that much lift on my front end. Made my
Spring hanger so I could still unbolt my bumper. Have lots of pictures if your interested. Also in my series 3 run a 200tdi, Ike front bumper with winch and sliders so my front end is heavy
Also I run parabolics in the rear

Shared via Tapatalk H


Sent from my iPad

bullstanky
03-22-2013, 04:44 PM
You want to have a shackle located at both the front and back of the front springs? If so, that won't work. You need a fixed mounting point at the front of the spring. Maybe I'm not understanding exactly what it is you want to do at the front of the springs.

Oh yes, I'm adding a shackle at the front end of the front spring. The plates on both sides of the new shackles on the front end of the front spring will be welded to the old spring mounts on the horn, creating the fixed mounting point needed. Repurposing and welding up shackles seems easier than fabricating a part to drop the front spring mounts to keep everything in alignment.

JimCT
03-23-2013, 08:46 AM
not sure the shackles will be strong enough without somehow boxing them in. Lot of side load in turns and side hills






Oh yes, I'm adding a shackle at the front end of the front spring. The plates on both sides of the new shackles on the front end of the front spring will be welded to the old spring mounts on the horn, creating the fixed mounting point needed. Repurposing and welding up shackles seems easier than fabricating a part to drop the front spring mounts to keep everything in alignment.

bullstanky
03-26-2013, 09:51 AM
not sure the shackles will be strong enough without somehow boxing them in. Lot of side load in turns and side hills

You make a good point. I'll likely have to box the shackles in and triangulate from the side of each shackle plate back to the horn. All the same, I think it's going to work out better working from shackles as a starting point rather than grindind the spring mounts off and fabricating something new, because the shackle set up will allow me to get everything in alignment before I weld it up.

And if I decide to take them off one day I can more or less just grind off the welds and take the shackles off.

jac04
03-26-2013, 12:46 PM
Make sure to post pictures of this modification when complete.

bullstanky
12-19-2013, 02:20 PM
I haven't the touched the springs, but I did put the military shackles on, using a shim to re-align the prop-shaft angle. It did give me a little more lift in the front, and drives fine, but I still have a good bit of rake from front to back.

I'm hoping that when I put the safari top and rack back on the weight helps even things out a bit.