'72 K5 - BYT - 1 ton swap

[ashman]

How much weight will the cage add? That's a line item in the order, but you haven't gotten there yet. Rear seat also isn't in. Since they're fairly soft and flexy, that'll flatten them out. I just don't know how much. But your shackle angle suggests they should be quite a bit flatter.

That is a very good point. I forgot that I'll be adding the cage still. Rear seat is in BTW. I changed mine up so that it can fold down several years back.

Ash,

Throw a couple hundred pounds of sand / cement bags in the back and drive it around for a couple of weeks.

I'll bet the springs settle-out on their own... but it's worth a call to ORD to confirm that this is the expected "stance" for a fresh set of springs.

-G

I have a bunch of sand bags around here, so I can simulate the cage weight, but these springs are 6" high at the moment, seems a long way to "settle".

I'll give ORD a call and report back. Sure would be nice if a couple of hundred pounds of cage is all that I need to fix it. That would be soft springs indeed! Fingers crossed.

 

[Truckman4life]

Just convert it to spring under and all will be ok.

 

[centexk5]

My ORD 4" lift springs are sitting at the same height as the 6" lift I just pulled off. Figured it was a combination of everything being torqued with no weight on it so everything is in a bit of a bind and everything just being new in general and not settled. Some quick driving should squat everything out.

 

[ashman]

I threw a bunch of stuff in the back to simulate the cage.


In all I added 630lbs.

It brought it down 3"

Before the weight:


It's still at least 3" taller than it should be.

 

[Greg72]

Jeepers.

I'd loosen up the bolts on the shackles and both spring eyes. Maybe something is super bound-up right now with no way to relieve the stresses....?

-G

 

[Greg72]

DUMB QUESTION: Is the truck in Neutral? If you did all this work in "PARK" it might be unable to settle out with the drivelines all bound up.

It's on a lift.....so raise it up and down a few times to settle it.

This one has me curious....


-G

 

[ktmoutfront]

You need to air it out a couple of times.

 

[Stephen]

They could just be wrong, they're spec'd out and built by people after all. But I looked through specs and nothing stands out as way off. There are a handful of things to check out to get started. Keep in mind that your shocks and axle position are set up without knowing anything about the spring rate so those things aren't going to change when the ride height comes down. This is a much smaller problem than it looks like right now, we'll get it figured out.

 

[skunked]

With that much weight your rear shackle angle shouldn’t be so vertical either.

 

[ashman]

They could just be wrong, they're spec'd out and built by people after all. But I looked through specs and nothing stands out as way off. There are a handful of things to check out to get started. Keep in mind that your shocks and axle position are set up without knowing anything about the spring rate so those things aren't going to change when the ride height comes down. This is a much smaller problem than it looks like right now, we'll get it figured out.

Thanks for looking into this for me.
I got most of the measurements you asked for. Unfortunately it doesn't look like I wrote down the free arch measurements.

Measuring the diy4x shackle flip, it appears to drop the shackle mount 1.25" lower than the stock hanger. (Measured from the lower mounting holes.)



Also, I do have 1" longer shackles.




The other measurement you asked for was ride height of my current front springs.


It's right at 13"

 

[ashman]

It's on a lift.....so raise it up and down a few times to settle it.
-G

I did just raise and lower it a couple of times, no change.

FYI, loading 630lbs in the back changes the center of gravity quite a bit. It got a little light on the front for sure!

 

[Stephen]

So there's a little over an inch of extra lift out of the flip and shackle system that we didn't count on in the rear. Not much but going the wrong direction for now. For ride height in the front you need to butt the tape against the axle tube. I'm guessing that will take you to about 15" of ride height which is about 6" of lift so the front is in the ballpark.

At this point it's going to be wise to put the fronts on and bounce it around a little with an appoximation of what will be in the back and we'll see if spring changes need to happen. And if you can talk the rear shackle bolt out to get a measurement of free arch it would help make sure we started where we were supposed to.

 

[ashman]

For ride height in the front you need to butt the tape against the axle tube. I'm guessing that will take you to about 15" of ride height which is about 6" of lift so the front is in the ballpark.

woops, measured that wrong. I'll double-check it in a bit.

At this point it's going to be wise to put the fronts on and bounce it around a little with an appoximation of what will be in the back and we'll see if spring changes need to happen.

Yeah, it's not looking quite as bad as initially thought. I'll go ahead and get the fronts in and report back.

And if you can talk the rear shackle bolt out to get a measurement of free arch it would help make sure we started where we were supposed to.

yup, I plan on that this afternoon as well.

 

[ashman]

I went out and measured the front axle tube to bump stop bracket, and yup, it's at 15-1/8", so 6" lift sitting right in the front.

I had @72gmck5 come by and jump in the back for a "little" extra weight. He was able to drop it another 2" just getting in, so feeling better about it. I'll measure the spring arch this evening.

 

[AJs72K5]

I ran a 4" shackle on mine with the flip. 2" springs netted 6" of lift. The 6" shackle you have also moves the wheel further forward even with setting the pin back in the spring pack like you did. I'm on the 1.5" hole on my perches to push the axle back closer to normal as is.

 

[ashman]

I ran a 4" shackle on mine with the flip. 2" springs netted 6" of lift. The 6" shackle you have also moves the wheel further forward even with setting the pin back in the spring pack like you did. I'm on the 1.5" hole on my perches to push the axle back closer to normal as is.

I still have my mock-up shackles so I'll play with a few different shackle lengths.

 

[ashman]

I unhooked the shackles and measured the spring free arch. 10" on the nose. I think that is what @Stephen said they should be.

While I was at it, I switched back to a 4" shackle.



Only made about .25" of difference.

On to the front...

 

[Truckman4life]

Here's the plan: Modify the wheel opening to match the tire radius and switch to 40s. Super simple. Maybe even 42s if you can handle being that badass!

 

[bp71k5]

I’m curious. Did you put your previous springs back on after the shackle flip? Those brackets can be swapped side to side to adjust where the shackle sits so I wonder how much of the height problem is from the shackle flip vs the actual springs. If you previously had 6” lift springs, then maybe it won’t help to compare, but if you put stock height springs back on, it might give you a clue.

 

[ashman]

unfortunately my previous springs were 6" lift as well. I do have another blazer with stock springs on it, but I really, REALLY don't want to go put that up on blocks just to pull the springs and see what happens.