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Old 11-03-2011, 12:49 AM   #1
siresigon1
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12" lift for front of 72 blazer?

hey guys what do you recomend is a good way to get 12" of lift for the front of a 72 truck/blazer. This is what i have now but i dont really like the set up. 8"spring,1" add a leaf for dyi, 2.5" shackle(only 11.5). I would love to do a 4link but i cant afford that right now. Thanks for any help.
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Old 11-05-2011, 01:37 AM   #2
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Re: 12" lift for front of 72 blazer?

I think that it is INSANE putting 12 inches of lift on the front of that truck. But, if you have to, you can build a "box drop" for the front of the spring and shackle. Most will consider that "hack-job" though.

Or

You could buy 12" springs from Deaver, Alcan, or National. That being said, why so stupid high? What are you going to do about steering? Even a good cross-over won't work well with 12" of lift. Driver shaft angles? With 12" of lift, you'll have more tire than the 1/2 ton axles will handle.
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Old 11-05-2011, 05:40 PM   #3
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Re: 12" lift for front of 72 blazer?

8 inch lifted 52 inch springs.
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Old 11-08-2011, 02:15 PM   #4
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Re: 12" lift for front of 72 blazer?

Sky off road makes a 4.5" drop hanger kit for the front, it takes some welding but its beefy. The kit plus your 8 inch springs = 12.5
Im going to use it on my truck for ten inches of lift. What size tire is in the pic? It looks good the way it sits but you can always go higher
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Old 11-08-2011, 11:28 PM   #5
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Re: 12" lift for front of 72 blazer?

the tires in the pic are (bald) mock up 38". i have already done the 1 ton axle swap and 12+ crossover steering. I figured 12" springs would be the easiest but i know the bigger the spring the rougher the ride. hey bikes&bowties did you mean i should use a 52" rear spring swap kit and 8" rear springs would = 12" of lift ? is that how the stackup works. thanks for the input guys. my goal is to run 40" tires. I know its not the most feasible but its just something i've always wanted to do.
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Old 11-08-2011, 11:50 PM   #6
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Re: 12" lift for front of 72 blazer?

But you could run 40s with much less of a lift =-p interesting setup though haven't seen alot like it
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Old 11-10-2011, 01:10 AM   #7
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Re: 12" lift for front of 72 blazer?

Asking for trouble.
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Old 11-10-2011, 06:56 AM   #8
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Re: 12" lift for front of 72 blazer?

Your first stack up doesn't really add up to 11.5 ya know... the shackles only yeild half the extra length you've added. Longer shackles in the front will end up screwing your caster pretty bad, so the drop front brackets would most likely help get that back into spec.
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Old 11-10-2011, 10:42 PM   #9
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Re: 12" lift for front of 72 blazer?

its to bad everyone that looked at this post has a negative comment on a 12 inch lift..

go to diy4x.com and get the genI axle flip n switch for the rear which is 4.5" of lift alone then go with an 8in spring and then the 52in front leaf spring conversion for the front with a 4.5"shackle. the longer the spring will make up for the arch lift and wont be as rough. caster is nothin to worry about with that shackle either i have it on mine its not like the tires will wear faster or anything and it won't be noticeable. 12inches of lift is a badass idea doont listen to others lol
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Old 11-11-2011, 01:22 AM   #10
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Re: 12" lift for front of 72 blazer?

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Originally Posted by JDeere550 View Post
its to bad everyone that looked at this post has a negative comment on a 12 inch lift..

go to diy4x.com and get the genI axle flip n switch for the rear which is 4.5" of lift alone then go with an 8in spring and then the 52in front leaf spring conversion for the front with a 4.5"shackle. the longer the spring will make up for the arch lift and wont be as rough. caster is nothin to worry about with that shackle either i have it on mine its not like the tires will wear faster or anything and it won't be noticeable. 12inches of lift is a badass idea doont listen to others lol
HUH? First, caster doesn't wear the tires. Toe in/out will wear tires. Caster most often causes "death wobble" and other wandering/handling issues. Don't get your caster wrong! Second, just because you can mix and match parts doesn't mean you should. The only part of that whole thing that sounds even close to right is that the longer spring will make for a slightly softer ride.

I think that you're talking about a SHACKLE flip n switch. 52s alone in the front won't give you 12" of lift. I used a 7" shackle (yes, even at the proper angle) and only got about 5" of lift. I had to use a panhard rod due to how soft the springs are.

I don't want to sound too negative. I am actually a safety nut (sorta). I'd rather your rig be safe on the road than big. If you want 12" of lift, you'll sacrifice handling and safety. 12" on a budget is not really possible. Just about everything needs to be address...which means it cost money.

This is with a 1" drop on the front of the 52" springs and a 7" shackle. It handled flawlessly on the road and performed awesome off road. It was still no where near 12" of lift. Add to that, it was actually expensive to build.


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Old 11-11-2011, 03:19 AM   #11
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Re: 12" lift for front of 72 blazer?

yeah if you read correctly i was saying caster will not wear the tires, and i stand corrected i did mean shackle flip n switch typin fast messes me up, and a 52" leaf spring has multiple applications of lifts fyi. meaning 52" spring could have a 6 or 8 inch lift...also if you got a truck to go off the road with im pretty sure youre not worried about handling on the streets or going to fast which would lead to lack of handling around a corner, i go 60 down the highway . the way your drive your rig decides on the safety just as much as what setup you choose, gotta know how to drive watch ya got. and im pretty sure this boy here ain't making no pavement princess.
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Old 11-11-2011, 08:00 AM   #12
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Re: 12" lift for front of 72 blazer?

Driveshafts?............/.\
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Old 11-11-2011, 11:34 AM   #13
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Re: 12" lift for front of 72 blazer?

What I would do, out of simplicity, is do the 52 inch spring swap like suggested with 8" 52's. Should net 12" of lift, approximately. If you already have the 1 tons and crossover steering, you should be set other than the driveshafts. You can have yours lengthened or have new ones built, which is what I would do. It might be more pricey, but new ones are easier to balance than ones that have been cut and lengthened. What gears are you going to run with the 40's? Just curious. Good looking rig!
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Old 11-11-2011, 08:00 PM   #14
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Re: 12" lift for front of 72 blazer?

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Originally Posted by JDeere550 View Post
yeah if you read correctly i was saying caster will not wear the tires, and i stand corrected i did mean shackle flip n switch typin fast messes me up, and a 52" leaf spring has multiple applications of lifts fyi. meaning 52" spring could have a 6 or 8 inch lift...also if you got a truck to go off the road with im pretty sure youre not worried about handling on the streets or going to fast which would lead to lack of handling around a corner, i go 60 down the highway . the way your drive your rig decides on the safety just as much as what setup you choose, gotta know how to drive watch ya got. and im pretty sure this boy here ain't making no pavement princess.
Well put. Sorry that I misread your thread.

I do not agree with the thinking that an off-road rig does not do well on the road. I believe that a well built rig does both very well. Because, after all, suspension/steering principals apply equally under all circumstances.

I am throwing more personal opinion with a bit of personal experience: A 52" spring swap with 8" lift springs NEEDS a proper steering/panhard rod!!! Otherwise, the flex/give in the springs and bushings will about let the truck "fall" over off the springs. The reason that you don't need this with 12" springs is because they were actually designed for that. They're STIFF. AND they're designed to be used with the "push/pull" steering that places load on the spring in the direction that they're most stable. Cross-over steering puts a side load on the spring. It wants move the axle out from under the truck because the springs have little stability in the direction. The benefit of using a softer spring becomes a prohibitive with that much lift.

Just to show that I am not a complete dickhead (I really don't mean to be), Siresgon1, you can have my panhard frame bracket. You just pay shipping from AK. I'm linked front and rear now and don't need it. Here is a photo of it. You can see it right in front of the steering box.

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Old 11-11-2011, 08:16 PM   #15
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Re: 12" lift for front of 72 blazer?

well i do gotta agree with that buckin bronco sticker on the back window!
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Old 11-11-2011, 08:23 PM   #16
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Re: 12" lift for front of 72 blazer?

i see where your coming from, different opinions and experience, im not a crawler guy i just ask for a little softness compared to the rediculous stiffness you get from the short almost completely U shaped leafspring, for my slow driveability, everday driving reasons. but if you go high, you just gotta learn on what your sacrificeing as in speeds, turns and bumps and i knew ahead of time what i was gettin rid of. thats why i got my bouncy bench seat B-)
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Old 11-13-2011, 09:03 AM   #17
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Re: 12" lift for front of 72 blazer?

For the push/pull pan-hard bar, what if you run a hydro assist? Would that take the stress off the rig?
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Old 11-13-2011, 10:22 PM   #18
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Re: 12" lift for front of 72 blazer?

Simply put, no. Let me TRY to explain...

Here is the principal difference between cross-over and push/pull: The length of the steering linkage.

Because the steering box is fixed to the frame and the connection at the axle is moving, there are infinite changes in steering geometry. The factory chose push/pull because its smaller and puts force on the springs in the direction that the spring has the most rigidity. Therefore no panhard. It doesn't need it.

We all now know that is no the best for on or off road performance.

Look at newer Fords, Jeeps, or Dodges. They all have some type of cross-over. They all use a panhard.

Here is why:
as the wheels move in suspension cycling, they generally move up and slightly rearward (in our leaf sprung trucks). The distance between pitman arm and the connection at the axle is changing. That means that either the drag link needs to get shorter or steering parts need to move. That is why in some truck, when you hit a bump, either: wheels steer or the steering wheel moves. Hence "bump-steer" The longer the drag link is, the less change in geometry as the suspension cycles.

IMAGINE using a 12" ruler. it is fixed at one end. as you moved the other end of the ruler up 12" and down 12" (24" total), the ruler swings 180 degrees in a half circle. NOW imagine using a 36" ruler. Move it up 12" and down 12". It may only move 60 degrees.

HERE IS WHY HE USE A PANHARD: Using a panhard with cross-over steering should be at the exact same angle and length of the drag link. That will force the axle to cycle in the exact same path as the steering. That means no bump steer. Great right.

Clear as mud?

Now, using hydro assist with push/pull:
All hydro assist does in any steering system is just that, assist. It in no way makes up for steering angles or controlls axle movement.

Here is why bigger lift makes things worse:
The springs are taller. The axle is farther from the spring mounting point on the frame. Imagine your axle as your hand, and the spring a wrench. Its putting force on a longer wrench. To resist that force it take more support. Also, the panhard and draglink are no longer horizontal (or close to it), they are at a much steeper angle. This makes a much more exaggerated bump-steer.

So, on a non-lifted truck, it does not take much to limited side-to-side (driver to passenger side) movement. As the truck gets taller (or springs get softer), a panhard is required. When the cross over steering pushes or pulls it moves the axle side to side rather than steering the wheels.

The panhard provides both stability laterally in the truck AND locates the axle under the truck.

Here is a FORD Solid Axle Swap (SAS) that I did a few years ago. Notice how the panhard and draglink almost at the same angle. In fact, you can't hardly see the panhard behind the draglink.

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Old 11-15-2011, 01:05 AM   #19
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Re: 12" lift for front of 72 blazer?

Thanks guys for all great info. I definitely Knew that talking about a 12" lift would be very controversial thats why i stated early on that i knew it wasnt fesible but it was just something that ive always wanted to do. Im leaning toward doing the 52" inch spring swap 8"rears, with a panhard bar(great idea) to help strengthen the side to side movement of the leafsprings. lukefalls is there a kit online or is it something that needs to be pieced together? where does the lower part of the panhard bar attach to? i could'nt see in the pics. This is where i am today. Im getting ready to sandblast and paint the frame this weekend then do the DIY rear disc brake conversion followed by a new crate motor,700r4,new driveshafts,and new gears(im thinking something like 4.88 or what ever one of you guys can suggest to run with 40's im open to any suggestions)
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Old 11-15-2011, 02:02 AM   #20
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Re: 12" lift for front of 72 blazer?

I'm glad that you decided. You seem to have read the good and bad and have a better idea of what you're wanting to do.

No, to my knowledge, there is no panhard kit. I did check Off Road Design. They don't have a kit listed on their website. I am SURE that they could make you an excellent kit. My panhard attached to the passenger side spring plate. That is not recommended, but it worked for me for several years. Its not recommended because it puts excessive load on the U-bolts, which they were never intended to have. AND its a bit too short. Using the space between passenger side spring pate and the knuckle works fine.

That being said, I personally prefer to deal with WFO Concepts. www.wfoconcepts.com Not because ORD is bad (in fact, they're great), but WFO is freakin' awesome.

Here is what I'd do:
spend about $80 on a "set" of 3/4 rod ends (WFO sells as a kit). Then buy about $30 worth of DOM tubing 1" x .120 (from a local metal yard). Then I'll give you my frame mount. You just pay the shipping. I'll get better pics if you want. I HATE Ballistic Fab, but buy a $12 axle mount for the panhard. You're done. When you have all that, "mock" up the panhard bar. Take a pic, and we'll review it together.

Let me know if I left anything out.
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Old 11-15-2011, 02:04 AM   #21
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Re: 12" lift for front of 72 blazer?

How are you going to use this thing?
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Old 11-15-2011, 02:07 AM   #22
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Re: 12" lift for front of 72 blazer?

hey you think panhard bar is really necessary with leaf springs?
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Old 11-15-2011, 02:10 AM   #23
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Re: 12" lift for front of 72 blazer?

i mean usually you only see it with coil spring applications, since leaf springs cover a larger area and coils are just a little area of support, you know what i mean?
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Old 11-15-2011, 02:30 AM   #24
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Re: 12" lift for front of 72 blazer?

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i mean usually you only see it with coil spring applications, since leaf springs cover a larger area and coils are just a little area of support, you know what i mean?
Actually, I am not sure what you mean. Are you asking why I only see panhard bars on vehicles with coils? The simple answer is that generally, coils do off less lateral control over the axle. That is where the use of links comes into play. Coil suspension and link seem to go together. Where leaf springs and shocks seem to go together. A double triangulated 4 link offers enough support to NOT use a panhard. Double triangulated is usually used on the back of trucks (because there is no rear steer, I'll explain in a minute) which is why you don't see panhard bars on the rear.

Parallel 4 links and most 3 links do need a panhard, which is why there are use more on the front. Why: Because a "properly" built triagulated 4 link cycles the axle in a plane that is nearly impossible to match in the steering. You DO see double triangulated front setups on Ultra 4 rigs with full hydro. The steering becomes independent on suspension geometry because its mounted to the axle. Leaf spring trucks, if the springs are soft enough or the truck is tall enough, need panhard bars. See below.

Here is my 3 link with a panhard.


Here is an Ultra 4 setup. I picked this at random. Look about half way down the page.
http://www.pirate4x4.com/forum/showt...=934912&page=3
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Old 11-15-2011, 02:57 AM   #25
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Re: 12" lift for front of 72 blazer?

yeah i know about using them with triangulated links and that, but usually ya don't see the panhard bar with leafs because the springs do have that advantage of lateral control over coils. so you dont think using a panhard bar with a leaf spring set up would be over doin it/spendin time on somethin you don't need?
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