Standard shackle flip, or inboarded shackle flip?

[Dmntxn77]

I have decided to go with 63" Cheby springs on the rear of my Cherokee. It is a post mount rig, and I already have all the peices that I need shackle flip it (thanks Tad).

BUT, I have been thinking, why go through all that effort (see Tads sig for details) when I can just inboard the springs under the frame.

I need to rotate my pumpkin up anyway, and I would rather just weld on new perches than as shims.

Plus, by moving the springs in (even a little) should give me better flex. Not that it is going to be a huge issue with the 63" springs anyway, but...

So, what do you think? Should I do a standard (post mount standard that is..) reversal, or should I inboard them first?

[Headhoncho]

I inboarded the stock rear springs on my j-10 and gained about 8-10 inches of lift. I had to remove my blocks to keep the rear the same height as my front with 4" springs and a springover.



jr

[Dmntxn77]

Yeah, I should do some research to see how much lift 63" springs give over stock springs..

I dont mind having the rear a bit higher than the front anway. Plus, I can always cheat the front up close to an inch with Cheby shackles..

[jepj2000]

I asked Tad how much the ride hight would increase by moving 63s under the frame and he said without the overload on the 63s it sat about the same as a front SOA and 2" lift springs.

I plan on mounting my 63s under the frame. If your going through the trouble mine as well do it the best you can the 1st time. Go with 63s under the frame IMO.

Rankin

[Dmntxn77]

I asked Tad how much the ride hight would increase by moving 63s under the frame and he said without the overload on the 63s it sat about the same as a front SOA and 2" lift springs.

I plan on mounting my 63s under the frame. If your going through the trouble mine as well do it the best you can the 1st time. Go with 63s under the frame IMO.

Rankin

Those are the numbers that hoped for.. That will be perfect since I was running 2" rear springs with my SOA front before..

Of course, once I chop the top, it will probably raise the rear even more.. :thumbsup:

[jepj2000]

Yeah should be perfect!

It may not raise up that much due to that bad ace jungle gym you have on the inside of that beast:thumbsup:.

How long do you think it will be before you do the swap?

Rankin

[Dmntxn77]

Yeah should be perfect!

It may not raise up that much due to that bad ace jungle gym you have on the inside of that beast:thumbsup:.

How long do you think it will be before you do the swap?

Rankin

Nah, a couple hundred feet of HREW is as light as a feather.. :thumbsup:

As far as the 63" spring swap, I plan to make it my next mod. Well, next after the cage gets finished, and the front pinion gets rotated.. I wont have my Jeep back before that..

I have to get it done along with my T-18/D20 swap before I try to fit a rear driveline...

[Tad]

I asked Tad how much the ride hight would increase by moving 63s under the frame and he said without the overload on the 63s it sat about the same as a front SOA and 2" lift springs...
That's correct, without the big honking overload those springs have.
If you think about it, the rear hanger on a SF is at the same height as being under the frame anyway, the front of the rear SF hanger sits about 1/2 - 3/4" higher than the bottom of the frame.
I doubt it's going to change the height much more than that 1/2 - 3/4", if that.

It will however bring into play making sure everything gets positioned and squared up properly but it's just math and with some good measuments taken before and a few consistant reference points, I doubt it will be that hard.

[elbastardo]

Not to hijack the post.......To much:rolleyes: With a spring that long and a pack that thin how much axle wrap do the chevy 63s get? Are they running bam bars to compensate?

[Tad]

With a spring that long and a pack that thin how much axle wrap do the chevy 63s get? Are they running bam bars to compensate?
I'm not running anything besides the 7" anti-wrap perches.
I am sagged on the drivers side about 3/8" after almost 2 years.
Might just be the weight from me.

[Slick Willie]

I put my 63's under the frame, and I recommend it. I needed the extra few inches of lift for clearance though. The front sat lower, but I got some saggy 4" front springs and now my front is a hair higher.

Rear shackle angle makes all the difference on rear lift. I screwed up the first time, the shackle was pointing backwards straight, then I put new holes in the hangers, and when the shackle pointed down at an angle like it's supposed to, the rear sat a couple inches higher than before. Those 63" spring shackles are pretty long too.

I took out the overload spring to get better up flex. Now, when I stuff the rear tires, the spring actually flexes up so much that it inverts a little (couldn't do that with the overload spring). Besides...the overload spring is only about 3/4" thick, compared to 3/4" less lift and the few inches of up flex you'll gain without it.

Yes, they're nearly as long as I am tall, so they definately flex good, but with that comes axle wrap. Most of my wheeling is crawling so far, but when I do get on loose dirt or decide to throw stuff behind me, it wraps pretty bad. A trac bar is on my list, and I'd say it would be a good idea for those with 63's that plan on spinning their tires often.

For an axle wrap video, ff to after the 1:00 mark on this one:
http://youtube.com/watch?v=N9iRIHnT9uk

[jtr]

The only bad thing about the 63"s is they have soo much droop. In my case the rear axle would droop so far (think suspension unloading-high speed wash) that the CV would exceed 22 degrees thus causing complete failure of the CV.


I had to put a limiting strap on the axle, no problems since but it was an expensive lesson. Take the time to figure operating angles of the driveshaft components or be prepared to spend some cash learning the hardway.

[Slick Willie]

That brings up a good point. My rear driveshaft is about 5' long, so the angle doesn't get hurt much when it droops. My rear pinion is pointed at the tcase, but the tcase yoke sees a little angle. Shorter DS length will obviously see more angle.

[Dmntxn77]

My concern is for the slip travel of the drive shaft more than the angle. With the DS length, I dont think that the angle will be too difficult to overcome. Slip travel on the other hand is expensive..

Maybe I will just make a square rear shaft...

[Slick Willie]

The shackle is in the rear, so when the axle droops, the axle goes forward, causing little slip travel. There will be more with a shorty than a long one, but still not a whole lot. When you get it all settup, you can flex it and measure. I never did since I have like 2' of slip, but still. It's not much. If you reverse shackle the front, you need a high slip DS. I don't know anyone who reverse shackles the rear. I wouldn't recommend it.

[Stuka]

If you had a front shackle in back it would be **** near undriveable. The axle would be going all over the place.

Oh, and if you go with a square rear shaft, don't plan on any HWY driving. As you cant balance them, and they will shake your truck apart.

[Dmntxn77]

If you had a front shackle in back it would be **** near undriveable. The axle would be going all over the place.

Oh, and if you go with a square rear shaft, don't plan on any HWY driving. As you cant balance them, and they will shake your truck apart.

Yeah, I have no intention of doing a rear shackle reversal.

Reagarding a square rear drive shaft, I have heard both ways as far as how much vibe they have. Some say what you said, and others have said that it is as smooth as can be..

Have you had personal experiance with one?

[Tad]

The only bad thing about the 63"s is they have soo much droop. In my case the rear axle would droop so far (think suspension unloading-high speed wash) that the CV would exceed 22 degrees thus causing complete failure of the CV... I run 1410 yokes/joints in the rear so that has not seemed to have been an issue, my shocks limit my droop (not a great idea I know) but to fix that I will have to cut up through the bed since I refuse to rotate the shock mount on the axle back down to that drag-on-rock stock position.
I will eventually cut up into the bed, but for now I live with it.

[jtr]

I run 1410 yokes/joints in the rear so that has not seemed to have been an issue, my shocks limit my droop (not a great idea I know) but to fix that I will have to cut up through the bed since I refuse to rotate the shock mount on the axle back down to that drag-on-rock stock position.
I will eventually cut up into the bed, but for now I live with it.

Are you saying that yo are not using a CV at the t-case end? That worked for me (one u-joint at each end) until I put the doubler in and put the complete drivetrain above the frame rails. This created an extreme driveline vibration for a single u-joint set up and required me to go CV style. It can work but I was not willing to sacrifice a "flat belly" for re-using my driveshaft. BTW my CV set up is slilky smooth at 65 MPH.

[Tad]

Are you saying that yo are not using a CV at the t-case end? Not for the rear, the only vibration I have is from the welded Gov-Loc right at deceleration (it's great for a trail rig but it is a huge mass), but I don't run a doubler either, just the Dodge 208 mated to the TH400.

208 1410 compared to the D20 1310 rear shaft.
http://members.cox.net/pmountsoa/Day16/01rearshaft.JPG
http://members.cox.net/pmountsoa/Day16/01jointsize.JPG

Rear Angle
http://members.cox.net/pmountsoa/Day16/04rearangle.JPG

TCase Angle
http://members.cox.net/pmountsoa/Day16/05frontangle.JPG

We are bit of of Robert's topic but I think moving the rear axle back that 5-6" really helped with the angles.

[Stuka]

Yeah, I have no intention of doing a rear shackle reversal.

Reagarding a square rear drive shaft, I have heard both ways as far as how much vibe they have. Some say what you said, and others have said that it is as smooth as can be..

Have you had personal experiance with one?

I suppose it ultimately depends on gearing. As that will change the speed that the drive shaft spins at. Fopr instance on my J10 with 4.56's and 34's, the drive shaft is spinning pretty fast. But if I had 39.5's or something with 4.56's, its spinning MUCH slower, so vibes will be less of an issue. But because of the shape, there is no real way to balance them.

[Slick Willie]

My front square DS rattles like a bia, but I have a hole in the floor to watch and hear it. :D The rear doesn't seem to make noise, but I can't hear it over the squeaks, rattles, exhaust, and noise. Vibrations? I haven't got it over 20 mph due to death wobble. Plus I don't have shocks. I guess what I'm saying is I don't have good information for ya. All I know is that they're pretty dang strong.

[Dmntxn77]

My front square DS rattles like a bia, but I have a hole in the floor to watch and hear it. :D The rear doesn't seem to make noise, but I can't hear it over the squeaks, rattles, exhaust, and noise. Vibrations? I haven't got it over 20 mph due to death wobble. Plus I don't have shocks. I guess what I'm saying is I don't have good information for ya.

:lol:

[Dmntxn77]

208 1410 compared to the D20 1310 rear shaft.

http://members.cox.net/pmountsoa/Day16/01jointsize.JPG






Thanks for that pic Tad.. I knew they were bigger, but I didnt have a clue that 1410's would drwaf the 1310's like that.. :eek:

[jtr]

My front square DS rattles like a bia, but I have a hole in the floor to watch and hear it. :D The rear doesn't seem to make noise, but I can't hear it over the squeaks, rattles, exhaust, and noise. Vibrations? I haven't got it over 20 mph due to death wobble. Plus I don't have shocks. I guess what I'm saying is I don't have good information for ya. All I know is that they're pretty dang strong.

What's death wobble?(kidding) Just drive it to the trail:D

[Tad]

Thanks for that pic Tad.. I knew they were bigger, but I didnt have a clue that 1410's would drwaf the 1310's like that.. :eek: Yea, they are big!
Yokes:
http://members.cox.net/tad4sale/sobig.JPG

A = 14 Bolt 1410
B = GM 205/Dodge 208 1410 (can't speak for others, wish I could).
C = Dodge 208 1310

[Slick Willie]

What's death wobble?(kidding) Just drive it to the trail:D

Maybe when I rebuild kingpins and do hydro. Then my TRE's won't be worn out, the nuts will stay tight, and I won't feel like I'm in a paint shaker once it shifts out of first. :thumbsup:

1410's are beef. Actually, anything compared to 1310's are beefy.