did a search and didnt realy find anything other than johnny joints for frame-under shackle mount for the front of a tacoma. what i need to find out is has anyone moved their front shackle mounts on fullsize chevy (specifically k30) to correct shackle angle and what is the best solution to this problem. was thinking to just cut a hole and reposition the hanger in the frame forward a few inches but i would also like to know is this the best option or just get longer mains which on my chevy one ton might be a hard task. right now im utilizing 8 inch springs and 6 inch shackles and have a problem with the shackle sitting way too forward not to mention my lack of droop.

MOVE THE FRONT HANGER FORWARD TO THE NEXT SET OF HOLES ON THE BODY MOUNT. GET SOME 4" REAR SPRINGS AND YOUR SHACKLE IS ALREADY LONG ENOUGH.THE REAR SPRINGS ARE LONGER AND FLEX EXTREMELY WELL,SO MUCH THAT ON MY BLAZER MY DS PULLS APART AND I STILL HAVE 3" MORE DROOP! I AM USING 4" REARS AND SOME ZERO RATE ADD-A-LEAVES WITHOUT AN OVERLOAD SPRING,AND IT PUTS ME RIGHT WERE I WAS WITH MY 8" SPRINGS.

Originally posted by scottsdalerob
right now im utilizing 8 inch springs and 6 inch shackles and have a problem with the shackle sitting way too forward not to mention my lack of droop.

What bracket are you using to flip the shackle? You can also move that back, if you want your axle to stay where it is. I moved my shackle flip bracket (shackle hanger) back one set of holes and drillled new holes for the rear of the bracket. If you move the front forward, you're moving the whole axle forward, probably stuffing your tire into your fender well.

91blazer, why would he want to get 4" springs, when he's already using 8" springs?

Originally posted by Grendel


What bracket are you using to flip the shackle? You can also move that back, if you want your axle to stay where it is. I moved my shackle flip bracket (shackle hanger) back one set of holes and drillled new holes for the rear of the bracket. If you move the front forward, you're moving the whole axle forward, probably stuffing your tire into your fender well.

91blazer, why would he want to get 4" springs, when he's already using 8" springs?
im talking about the front springs.the longer shackles i use so the rear of the FRONT springs doesnt hit the frame.
i dont know what 'flip' you are referring to blazer , but since you are mentioning it i am running the ord 4 inch flip kit and the rear is perfect , it's the front shackle being too far forward.(negative shackle angle?)

pretty certain he is talking about front springs as they are the only ones that suffer from horrible shackle angles

there are currently 2 threads on CK5 discussing this exact problem
Baddog posted a few pics of his k30 frame relocation and resultant shackle angle

http://www.members.cox.net/russhuffman/junk/shackle.jpg
Baddog's

Originally posted by scottsdalerob

im talking about the front springs.the longer shackles i use so the rear of the FRONT springs doesnt hit the frame.
i dont know what 'flip' you are referring to blazer , but since you are mentioning it i am running the ord 4 inch flip kit and the rear is perfect , it's the front shackle being too far forward.(negative shackle angle?) IM TALKING ABOUT THE FRONT ALSO, PUT REAR SPRINGS UP FRONT ,GET IT?BESIDES I NEVER SAID FLIP ANYTHING.ANYWAY REAR SPRINGS ARE LONGER THERE FOR YOU HAVE TO MOVE YOU FRONT HANGER FORWARD TO KEEP THE FRONT AXLE CENTERED , THIS ALSO FIXES THE SHACKLE ANGLE PROBLEM AND YOU GET MO BETTER FLEX AND RIDE QUALITY.BUT REMEMBER IF YOU PUT REAR SPRINGS IN FRONT ADD 4" TO THE ARCH OF THE SPRING,ie. STOCK REAR SPRINGS IN THE FRONT WILL NET 4" OF LIFT. REAR SPRINGS WITH 4" OF LIFT WILL NET 8" OF LIFT WHICH I WHY I SAID GO WITH 4" REARS IN THE FRONT, THAT IS WHAT I DID BECAUSE I PREVIUOSLY USED 8" FRONT SRPINGS .BY THE WAY IT IS REFFERED TO AS A 52" SPRING SWAP BECAUSE THE REAR SPRINGS ON A HALF TON ARE 52" LONG APPROXIMATLY 4" LONGER THAN YOUR FRONT SPRINGS......YA FEEL ME BROTHA.....

now i gotcha! it was late last nite what can i say! sounds like that will work perfect. was thinking about a different setup for the spring mounts up front anyway . cage? thx -rob

I just finished doing the shacle move
I used the existing top forward bolt and redrilled the other 3
I am going to need a longer shackle yet again
this thing gets taller everytime I look at it

MJs right, it's very easy to do. But, you have to be aware that the rear eye is going to want to get closer to the frame as the spring flattens when the axle stuffs. Just follow the radius described by the shackle to see what I mean. To calculate worst case, measure the arch length of the main spring, simulate cycling up to the bump stop (or till flat depending on arch/lift – past flat will start to move away again) and see where that puts the eye. This will allow you to calculate the minimal shackle CL length. But, after moving my entire suspension forward, my rear spring eye is actually slightly higher than factory and I have no problems with clearance. This is such an easy mod and has such dramatic benefits on SA GMs, I can’t image why it’s not more common…

but how does the spring swap affect daily driveability and towing? i prefer to not find out the hard way....on something like this....

Originally posted by mj
I just finished doing the shacle move
I used the existing top forward bolt and redrilled the other 3
I am going to need a longer shackle yet again
this thing gets taller everytime I look at it
mj, i follow you on the top forward bolt asignment , i see how there wouldnt be enough room to utilize the bottom forward hole cuz the bottom of the frame rail is in the way , seems like in order to get the same on both sides i could just mark the other three holes with the mount spaced above the frame rail with a piece of flat stock (1/4 - 3/8 inch) layed in the bottom of the frame rail to spot the mounts the same on each side. longer shackles not a prollem. seems like a way easier fix than some of the other posts. i assume you cut the rivets out w/a torch? you got any pic's of resulting shackle angle? vs previous maybe? thx rob
btw what you describe is different than the pic above in that none of the existing holes were utilized , however i think FOR ME ,that in that pic just the little bit of distance back to the top upper hole would do me better.

Originally posted by leadfoot067
but how does the spring swap affect daily driveability and towing? i prefer to not find out the hard way....on something like this....
I don't think it will make much difference honestly. It will reduce your effective spring rate. But in most cases lift springs ride pretty harsh so this is likely an improvement. The required longer shackle will also put more stress on bushings reducing the service interval. Additional leverage would also place more stress on the bolts too. The longer the shackle, the more issues will arise. But I don't think either of these is as onerous as the problems caused by the poor spring design used for lift springs on GM trucks. There is also the fact that we are negatively affecting service intervals and long term reliability with quite a few other common mods. As usually, it's all about your comfort level and goals.

As for towing, other than change in the spring rate, I can't see this having any effect. But IMO, towing with a K5 is already marginal at best...

I’ve actually talked to the techs at BDS about the design and why they don’t simply correct the spring shape to miss the frame and provide a longer shackle as part of “the kit”. Basically it comes down to cost and additional liability. Cost wouldn’t be but a few more dollars, but well over 99% of their customers don’t even know there is an issue, so competitors with simpler kits would win. The liability issues arise for the items I just listed above.

Originally posted by scottsdalerob

i assume you cut the rivets out w/a torch? you got any pic's of resulting shackle angle? vs previous maybe? thx rob
btw what you describe is different than the pic above in that none of the existing holes were utilized , however i think FOR ME ,that in that pic just the little bit of distance back to the top upper hole would do me better.
I would not recommend a torch due to excessive damage of surrounding material. My preferred method (after years of doing this) is to use a ¼ stone on a 4.5” grinder (or similar) to slot the head of the rivet like a common slotted screw. It takes about 30 seconds to slot them all the way to the bottom of the head on the ones that are not obscured by other things. Just don’t go too far and get into the frame. Then, using an air chisel, it’s easy to fold the 2 sides into the slot and shear them off. Finally, use a “punch” bit to knock the remains through. In ideal situations, where the rivet is easily accessible and there is only a single shear that is not in a bind, I can remove 1 rivet easily in under 2 minutes. If it’s in a bind, or with double shear (or more) punching it through can be nearly impossible and I’ve had to drill a few for this reason. Especially on the rear spring front hangers of my K30 which are double shear and bound due to frame flex. If I can’t get the grinder to the head, I just wail on it with the air chisel, but this takes longer, jars your fillings loose, and generally likes to chew up the surrounding steel more than I would like. Sometimes you have no choice…

That picture above is from my Truggy. As for using an existing hole or not, that’s up to you and how much angle you want in the shackle. If your really interested in doing it right, you could figure the effective rate of the spring you desire, calculate the angle that will give you that rate, and put the shackle where it needs to be. Arc radius length also has some effect due to leverage and shorter radius shackles change angle more for smaller movements, effecting rate. And on and on and on… Also, remember that I said my whole front suspension is moved forward. It’s actually about 2.5” forward and I run a 2” longer front main leaf too. So, MJs location probably gives him almost exactly the same angle as mine shows, even though he didn’t move his casting quite as far.

I guess the summary is that you need to look at your own truck and goals to figure out what you need to do. I would not advise anyone to just copy what they see on another truck unless all relevant details are functionally the same. Your looking at what I did for my stripped to the bone truggy that is off road only. MJ is working on a full bodied C/K30 home brew creation with a full body that is driven more-or-less daily (AFAIK). Furthermore, if I had it to do again, I would have actually gone a bit further, but this was just a first pass. Right now I’m not sure if I’m going to link the front, or move it further. Only small problem is I’ll have to repair the frame before moving it again since it will only be a small offset. Good luck on your project.

[QUOTE]Originally posted by BadDog
[B]
…

Arc radius length also has some effect due to leverage and shorter radius shackles change angle more for smaller movements, effecting rate. And on and on and on… Also, remember that I said my whole front suspension is moved forward. It’s actually about 2.5” forward and I run a 2” longer front main leaf too. So, MJs location probably gives him almost exactly the same angle as mine shows, even though he didn’t move his casting quite as far.





good point ! the way mj describes however, i can use existing springs:D

with my 5" shackles the springs are a little more then a 1/4" from hitting the frame rail
so I will be adding about 2" ASAP
hard to tell from the close up what the angles are but they look real close
I think your K30 frame has a slightly different shape in that area then my C30
I am going to weld the piece I holesawed into the old opening to fill it

I used a piece of paper to take a rubbing of the bolt pattern
and transfered it to locate the mount holes
then used some long 7/16" bolts to hold the shackle mount in the new position and slide a centre punch through the shackle to mark the holesaw centre
a 2" Morse was a bit big but doesnt look to bad IMO

my hanger was pretty much back into the body mount
the mount was notched slightly for the rear upper bolt clearance
so it may have been to far back

i already have fabbed a pair (set) of 7 inch long shackles when i did the 9 inch spring , had to cuz the stock shackle was out of it from the get go. so i might not even have to change the shackles.
and yeah, the k 30 frame slopes up too far within the width of a mount to use both forward holes.
i didnt understan your last sentence tho :D
(7 1/4 total length app. 5 7/8 from center to center on the shackle)

My apologies.

I used a aftermarket (slick rock) Jeep CJ rear spring hanger on the bottom of the frame. Allowed me to drop the shackle mount, place it where I wanted to for shackle angle, use a shorter shackle with same lift and obtain more flex. Used one existing hole, drilled the other and braced it inside the frame.

I just added the 7" on centre shackles
so the springs are off the frame
around the block test drive...
it actually feels like there are SPRINGS under my truck for the first time in 10 years

Baddog brought it up
my truck is full bodied, uncut, shortbox
C30 frame, cut down, and converted to 4x
10 superlift springs with teflon pads added
horribly stiff
I have been preaching long shackles on CK5 for a year or 2
the 2 threads on CK5 and this thread finally made me practice what I preach a bit
bandaid til the links go in

This is not exactly what you are looking to do but it might give you some ideas. I used ford 57" springs up front. I don't have the acual dims with me but I'll give you some estimates. Front hanger has been moved 3.25" forward and 3.25" up. Rear has been moved 1.5" back and uses 7" eye-to-eye shackles. Use a 10 degree welded on shim to restore caster. Axle is about 3-7/16" farther forward from stock.

http://www.m4x4a.org/ImageGallery/album136/Dscf0074.sized.jpg

http://www.m4x4a.org/ImageGallery/album136/Dscf0075.sized.jpg

http://www.m4x4a.org/ImageGallery/album136/Dscf0076.sized.jpg

looks like you laid the hangers on their side as well

www.pjtpw.netfirms.com

Check out this guys hangers.Well thought out and done. So wellin fact that I made two sets and used the second set to move my rear srings under the frame rails. Hope that helps,Todd