I’m currently running the stock rear leaf pack and stock 4" block in the rear of my truck. Each spring pack has a broken leaf. I beat on the truck hard at times when I was running 38's. I didn’t have a problem with axle wrap. I’m concerned that with the increased bite of the 42's, I may risk spitting out a rear block. A few years ago, I had a full size Bronco spit out a lift block on the trail. It was the biggest fawking mess that I have ever caused on the trail. :eek: Separating your rear axle from the frame is a great way to completely ruin your day. :D Anyway, I'd rather not travel down that road again.

What I am planning is buying 4" or 6" rear leaf springs, and getting rid of the block. The springs I’m considering are Explorer Pro-Comp...available through Summit Racing, NTW, 4 wheel parts, etc. They are rated at 320 pounds per inch.

Here are my questions:

1. When springs are advertised as “4" lift” or “6" lift” are they generally accurate? I haven’t bought any leaf spring packs in the past, so pardon the ignorance.

2. The truck isn’t light by any means. I carry two toolboxes, which are mostly full of tools, spare parts, jacks, extra fuel, fluids, etc. I’d guess that I carry at least 500 lbs of stuff in the bed. When I pick up a 42" spare, it may be closer to 600 lbs. Axle wrap is the main concern, so if it comes to losing a little flex vs. keeping the axle firmly in place, I’d rather err on the side of a stiff spring. Based on the weight in the bed, is 320 lbs per inch considered “stiff” or “soft” for a rear spring?

3. I’m leaning towards the 6" springs over the 4" to gain a couple inches in the rear. If the 4" measured a true 4", that would be OK, but I’d hate to get them then find they’re a little short and have to stick a 1" block back in there...defeats the purpose of the mod. Would you guys recommend the 4" or the 6" springs?

4. Jeff’s Bronco Graveyard sells degree shims to use between the spring perch and the leaf springs. My factory block is tapered somewhat. It angles the pinion downward. If I ditch the tapered block, is my pinion angle going to need corrected? If so, how many degrees do you think it’d be?

I’m sure someone on here has added rear lift springs to get rid of the factory blocks. Did you run into any unforseen problems? Were you satisfied with the mod when it was complete?

Thanks for any info.
Buford

Keep the stock springs, ditch the blocks, and invert the shackles.

Keep the stock springs, ditch the blocks, and invert the shackles.

this is what I was going to say, and if you carry a ton of extra weight a long add-a-leaf should fix the problem. If you have axle wrap problems new leafs, even super stiff lift springs arent the answer you need an anti wrap bar

Yeah, a shackle reversal and an add-aleaf would be a good, fix.

i have the stock pack, the 2" tall stock truck block, and a shackle flip, for a total of right around 7 " of lift.

If you have the 1 ton spring pack already just put in an add-a leaf and go.

doing the chackle flip will also point your pinion in the right direction, unless you are a crew cab long bed, then it may be a touch to much.

Joe

I've heard of the shackle flip for some time. I haven't researched all of the details, but I thought it moved the rear axle slightly forward and/or caused some pinion angle issues.

The truck is really and F-250 with a factory D60 front. I added the D70 rear. One of the main reasons I was looking at replacing the spring packs was due to the broken leaf springs....one on each side. The current setup has five leaf springs per side, counting the broken ones, and an overload leaf on top. I believe they are rated at 2700 lbs (27??) load capacity. Would they be stiffer or softer than the aftermarket spring rated at 320 lbs per inch?

Regarding the shackle flip, from what I have read (it's been a while, so bear with me) you:

1. Unbolt the spring pack from the shackle.
2. Cut/grind off the rivets.
3. Turn the shackle upside down, and bolt it back together (without the factory block).

Am I missing anything here?

Buford

Buford, that's pretty much all there is to the flip. It does move the axle forward but only a very slight amount. Check out my gallery on this site for some pics to give you a better idea: http://ford-trucks.com/user_gallery/displayalbum.php?&userid=113895&albumid=13227

With the shackle flip, does it improve or detract from the ride/handling/trail performance? Or does it ride/drive exactly the same?

Thanks for the info guys. Good write-up Ivan :beer:

Doesn't change the ride at all. If anything I'd say it's a little smoother but I also changed rear springs at the same time so it's hard to tell for sure. I have way better articulation than I did with the stock shackle setup. The only negative I've ever seen to a shackle flip is you can't haul quite as much weight with it as those shackles aren't designed for compression but if you're not shoving a ton of heavy shit in your truck it won't matter.

When I lifted my truck I had a set of springs made to that would eliminate the factory block and give me 6" of lift. I'm not very happy with the way these springs flex. They're pretty stiff. On the flip side, I can haul quite a bit of weight with them.

I plan on redoing the rear suspension once I'm done with my EFI and front 60 swap. I'll likely go with the hanger swap/shackle flip and some lighter, not so severly arched springs to soften things up.

Also, Ivan has a good point on the shackles. It's a good idea to either make a stronger set or reinforce the stockers if you do the flip.

My 2...

With the shackle flip, does it improve or detract from the ride/handling/trail performance? Or does it ride/drive exactly the same?

Thanks for the info guys. Good write-up Ivan :beer:


There has not been a change in performance on my rig,

accept when buring out, I got a pretty good wheel hop, so I think some sort of traction bar would be a good idea.

here are some more swap pics
http://www.supermotors.org/registry/vehicles/detail.php?id=3573&s=14629#content
http://www.supermotors.org/getfile/163668/fullsize/bko6.JPG

I have searched this topic quite a bit. Here is some useful information that I have found:

DRKelly-- beefing the stock shackles:
(If I do this, it appears to be an excellent way to do it).
http://www.pirate4x4.com/forum/showthread.php?t=291443&highlight=shackle

Saf-t scissors--: Good points….concerns similar to mine:
(Axle wrap is what I want to avoid).
http://www.pirate4x4.com/forum/showthread.php?t=257214&highlight=shackle


Jopes-- He has pro-comp rear springs:
(Seems to like them, or at least finds them to be acceptable).
http://www.pirate4x4.com/forum/showthread.php?t=260698&highlight=shackle

Pro-Comp products in general--:
(I read over ½ of it, and found more than one person with “broken leaf springs”) Kinda scary……..
http://www.pirate4x4.com/forum/showthread.php?t=204274&highlight=comp+springs+explorer


The shackle flip definitely has benefits, and everyone seems to like it. I’m just concerned that while it is effective at adding lift and getting rid of the factory blocks, it may “weaken” the rear suspension.

The rear lift springs that I was looking at apparently aren’t the “simple” answer that I thought they would be either.

I’m still debating on what to do. Reliability on the trail is most important to me. I’ll trade a little lost flex for a little added reliability.

I’m still weighing the options.

Thanks to all for the advice.

Buford

Update:

Last week I found that my passenger side rear leaf pack had three broken leaf springs.....only the top main leaf and the bottom leaf were intact. I bought ProComp 6" rear lift springs from NTW, ditched the factory blocks, added an extended rear brake hose, new rear shocks, and gained approximately 3-4" over stock height with the worn/broken springs. I took it on one trail ride and the springs seemed to work fine.

1. Unbolt the spring pack from the shackle.
2. Cut/grind off the rivets.
3. Turn the shackle upside down, and bolt it back together (without the factory block).

Am I missing anything here?

Buford


thats what I did on mine, well worth the time, but I don't see how some people claim insane lift from it..
I got 1" myabe 1 1/2" after doing it..

If you flip the stock factory hanger you only get 1-2in of lift. Most guys replace the hanger with another front one or an aftermarket hanger. This drops the shackle down even farther giving you more lift. I know if you take the front hanger off an F-250 and put it on the rear of an F-150/Bronco you get about 5in of lift.

thats what I did on mine, well worth the time, but I don't see how some people claim insane lift from it..
I got 1" myabe 1 1/2" after doing it..
Click on that link I provided above and look at the comparrisons. You can see with the final version I used a front hanger as BrokeCuzWheelin mentioned and it moved the eye of the spring down about 10" from its original position. This gave me a little over 6" of lift.

Update:

I have another trail ride on the springs, the end of which was spent with a CJ-7 winched tight against my rear bumper due to a non-running engine and broken steering. The rear springs have settled some, and the truck is nearly level. Originally, I thought the rear springs lifted the truck too much, with the blocks removed. Now I am very glad that I went with the 6" springs vs. the 4 inchers.

Buford

on my 83 i did the shackle flip useing the sky mfg mounts (4-6') lift stock shackle. I then added the belltech 4" drop shackles (in the flip they become lift shackles) so i got 10" lift but i ditched the stock wedge so i lost 1". i just had to trime the end of the rear bumper mounts. i got pictures here.
http://www.supermotors.org/registry/vehicles/detail.php?id=6364&s=20682#content
thiws was all done in the driveway.
mike