shackles vs. spring packs
 

I have an '03 7.3 CC 4wd with 35/12.50's on it. I have the front leveled by way of an extra leaf spring from the local spring shop. I like the way my truck looks right now but my tires scrub my fenders (not the liners but the rear corners of the fender flares) under very little compression. I was curious what the pros and cons were to each.

my understanding of it is that shackles will change your caster and depending on how big they are can effect your pinion angle, i went with spring packs, theyre all over ebay for around 100 bucks with u bolts. ive heard a few horror stories of people shackling up the front and the drive shaft slides apart at the slip yoke leaving very little spline contact area and locking it in and stripping out the driveshaft... just my .02

running a mini pack on my current truck, trouble-free almost two years now. ran a lift shackle on my last super duty, along with 4" springs and had no ill-effects either. the caster/pinion angle concerns makes perfect sense in theory, but i literally couldn't tell any difference (and i wheeled that truck, wasn't a street queen).

It's hard to go wrong with springs packs. Shackles can open up a whole new can of worms like Airframes4life stated, and can end up costing more in the long run. Since shackle lift only give you half amount of lift, you are going to need a lot of shackle to get any decent lift. I think anymore than 2'' (1'' lift) of shackle is beginning to pushing it.
}> I would just use lift blocks and be done with it. }>
Edit: The "lift blocks" was pure sarcasm. It is the absolute wrong way to do it.

its illegal to run front blocks in ANY STATE plus DANGEROUS, just buy a 4" lift kit with new front springs and be done with it, plain and simple

There are no laws in MN and many other states regarding front blocks.

It is still a bad idea though.

I've been running 2.5" lift shackles (provided 2.5" of lift) for going on 4 years and 32k miles and half of that is running in 4x4 high during the winter every day for 6 months.

absolutely no issues with steering, front drive shaft..ect

before i put my new pro comp 2.5" springs on i had the stock 4400lb front springs+tuff country 1.5" add a leaf+ 1" pro form lift shackle for almost four years and i never had any handling issues, other than a dump truck ride from the add a leaf. I changed the springs because i couldn't take the ride anymore and im debating adding my 1" lift shackle again to get me a little extra height up front

Your shackles are 5'' longer that stock ones?

My experience with lift shackles on my old FJ40 is the extra side to side leverage they provide. It makes the death wobble more possible.

stock on the bottom new lift shackle on tophttp://i57.photobucket.com/albums/g2...ent/015-10.jpg
http://i57.photobucket.com/albums/g2...ent/002-19.jpg

before
http://i57.photobucket.com/albums/g2...ent/005-23.jpg


after
http://i57.photobucket.com/albums/g2...ent/003-19.jpg

By springs do you mean spring packs?

In order to get the full 2" did you shackle both ends of the spring? Seems to me if you lift one end of the spring 2", by the time you go halfway back, where the axle is, you'd loose half the lift.

Will spring packs effect the ride or handling? Another question I've had since researching this topic is in regards to lift blocks. If the main concern is them getting spit out, why would a bolt through the center like the spring packs not work?

No, the front end of the spring does not move that mount stays stock. The longer shackle goes on the rear end of the spring.

Yes leaf spring packs.
From my experience paying the extra to do it right the first time saves you money, time, frustration, and is safer.

DO NOT use lift blocks! It is the last thing to use and probably the last thing you would use, after you wreck. That's what they did back in the day when it was all they had, and didn't know any better.
Spring packs are not all created the same. Some are built for flex (usually gives a softer ride, but has more body roll). Some are built to carry more weight(usually harder ride).

The shackle manufactures know this and when they build and market a 2" lift shackle it is engineered to give that amount of lift, so yes the actual shackle is more than 2" longer than the stock one.

Maybe a little confusion here, lift blocks, like you typically see on rear suspensions are a major no-no on front suspensions, they are illegal in my home state. Mini packs (a set of leaf sections comprised of 3,4 or 5 leaves arranged in a tapered stack) do in fact get through bolted along with the factory spring pack and are acceptable by my state's inspection stations. In my opion they are the cheapest way to lift the front but they are also the least desireable method. They do nothing for additional travel or load handling. Shackles at least increase your suspension travel to the bumpstops and new packs can give both increased travel and increased load handling (or a softer ride if thats what you want).

How much axle wrap come with the mini packs? I don't have any experience with them.

Okay, there is a difference between spring packs and mini spring packs. The spring packs are the leaf spring assemblies and the mini spring packs are the sections with a through bolt in them. Do the mini packs change the ride at all? As for the shackles, are they looked upon as being a safe way to lift a truck? I want clearance but I'm on a budget, I just had my trans rebuilt last week and that $2300 is sorely missed!!!

Some other things I was thinking about, with an added spring for leveling, how much more lift can I get away with without having to add longer brake lines? Also, which method will most likely not end up having to get another alignment? And lastly, if using the shackle, will the wheel look obviously off center to the fender?

I'm not entirely sure what you are asking here....... :-huh Axle wrap isn't a common problem with front suspensions except in pretty extreme situations like sled pulling and such as far as I know. I have no personal experience with mini packs either, just going on feedback from others that run them.

My advice would be to wait until your finances improve and get upgraded spring packs that will give you the lift you want and provide whatever type of ride and handling you desire. In my opinion, if it's worth doing, it's worth doing right! :-X22 My second choice if working on a budget would be to get the size shackles that would give you the lift you want, this will maintain the same ride that you currently have.

Thank you all for the answers to my questions. Sounds like the shackles will be my best option for the time being. I will do it "right" when finances provide the means, but until then I want to prevent further wear on my fenders and flares along with my tires.

That being said, any suggestions on what the minimum lift I might need is and how to maintain the level stance on my truck. Right now I'm bone stock in the rear and have only added one leaf to the front. I'm running 35's on 20 inch wheels. I'm thinking 2 inches will suffice going by the 1 inch wear pattern on my flares. Is there a solid rear block that will add the right lift or do I need to stack them (I'd rather not stack)? Also, if I go up 2" up front am I correct in thinking I need 2" in the rear, or is there some geometrical magic that requires more or less than what seems logical?

Yes, it is not common problem because lift block are not commonly used in the front with good reason. The lift block moves the axle away from the leaf springs and creates more leverage which causes the axle to wrap and "spits" the block out when the brake or power is applied.
The mini pack lowers the axle away from the original leaf pack, almost the same way a LB does. The the mini packs can have advantages over the LB since it can be longer in length to provide more support to the main pack, it is bolted to the main pack, and most are not as tall as LBs.

Adding a leaf spring to the rear would be the only thing I would feel safe doing. It is going to ride like a tractor.
Adding a taller single lift block make's it feel like your rear axle is bolted to swing set. You give it throttle and wait until it "swings back" before the truck goes.
Stacking blocks is asking for trouble. A new set of lift springs will seem cheap after you spit a block and cause a wreck, or best case scenario only have to replace a drive shaft, brake lines, and pay a tow bill.

This is the best advice you can receive.
I have been down that "rig it till you can fix right" road. It is filled with WHY didn't I just do right the first time!!!

I've decided to go with 2" lift shackles and 2" add a block, blocks. Reasoning is, with only two inches up front I don't feel like theres much difference between the mini packs and the shackles and the shackles appear to be easier and keep the stability of having the axle close to the spring. As for the blocks, I've read several articles in magazines where modest 2"-4" lifts were put on trucks and they added blocks to the existing ones. I don't abuse my truck off road and don't pull anything over 10k lbs.

Does anyone know where I can find one place to buy shackles and blocks as opposed to buying one from one and the other from some one else?

Another question too, I believe I have a 156" wheelbase (crew cab/short bed), would I need to stack tapered blocks or straight blocks with my existing ones?

Just put a Zone 2.5" leveling kit in my 2004 6.0 F-350. Couldnt be happier with it. Rides 10x better than before. I did get all new BDS shocks too. Installation was pretty stright forward but i would not recommend it unless you have air tools. other than that I would recommend it to anyone.

Blocks in the front? By mini-packs do you mean the little short spring pieces?

Nah, no blocks in the front. Just in the back. And yes mini packs being the little short minis with the rod or bolt through them.

Those are expensive garbage and unsafe in the front, plus they do nothing for spring clearance.

I was gonna go with 2" lift shackles up front for tire clearance.

As for front blocks being so bad. Why is about every heavy duty truck with front leaf springs have a lift blocks?? If you dont think so look at the next heavy truck you see. AND those trucks dont have track bars to center the axle. Just my .02 on this topic.

well my two truck's don't. 1995 GMC Top Kick 37k GVW no blocks up front leaf sit right on the front axle, 2005 Freightliner 37k GVW front leafs sit on axle

They probably don't want novices using blocks (not saying you are.) Those blocks you see probably have well fitted holes and pins in them etc.