Post mount shackle reversal. Will I need degree shims?

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Nikkormat
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Post mount shackle reversal. Will I need degree shims?

Post by Nikkormat »

I need new shocks anyway, so I'm looking at buying longer ones and finally doing a shackle flip.

Re reading Cappa's panel hack articles he mentioned that the pinion angle with the shackle flip was terrible.

Will I need change my pinion angle? That makes the install way more of a pain.
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Stuka
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Stuka »

Oh yes. Your pinion will be pointed up a bunch, which will result in some pretty bad vibes.

When I did mine, I also had a block, and I put them in backwards. This helped with the pinion angle quite a bit.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by AwesomeJ10 »

You pretty much don't want to run shims if possible. they seem to always want to kick out or break.

buy a couple of spring perches (from rough stuff), prep the assembly by loosensing all the ubolts, shackles, etc. Then bring it by and I will burn in the new perches along with watch you suffer while flipping the shackle/springs.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Stuka »

Blake wrote:You pretty much don't want to run shims if possible. they seem to always want to kick out or break.

buy a couple of spring perches (from rough stuff), prep the assembly by loosensing all the ubolts, shackles, etc. Then bring it by and I will burn in the new perches along with watch you suffer while flipping the shackle/springs.
You would have to move the springs under the frame, which would give him a lot more lift than he is wanting. The post mount springs don't have anything to weld a hanger to on the outside of the frame like box mounts do.

Also, with the thick side of the shim facing forward, the issue that typically causes them to kick out wont happen. As the force on the shim will be the opposite of normal.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by AwesomeJ10 »

hmmm

guess I've never messed with the post mount stuff.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Stuka »

Image
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Nikkormat »

Screw it, Jeep stays stock height. Thanks anyway guys.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by AwesomeJ10 »

just go SOA and 35's and get it over with man.

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Re: Post mount shackle reversal. Will I need degree shims?

Post by Nikkormat »

Blake wrote:just go SOA and 35's and get it over with man.
Nope the 74 is staying stock height until it can get 4 linked or swapped to a modern FSJ frame.

The 91 is getting lifted, I have a 4 inch Skyjacker kit and if that doesn't feel tippy I'll go higher. I've also got a set of flat top knuckles for high steer. So really I could go to a ten inch lift and be Brutus height. Or I could do shackle reverse and be SPOA height with a smoother ride and more travel.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Nikkormat »

Could I just have a double cardan put at the transfer case end of the driveshaft?
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Stuka »

Nikkormat wrote:Could I just have a double cardan put at the transfer case end of the driveshaft?
Yes, provided you shorten the drive shaft as well.

EDIT: Hmm, you have a QT, so the drive shaft will still have an angle. It may still work. but really, two shims cost what, ten bucks? Just get ones with centering pins and you will be fine.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Nikkormat »

Stuka wrote:
Nikkormat wrote:Could I just have a double cardan put at the transfer case end of the driveshaft?
Yes, provided you shorten the drive shaft as well.

EDIT: Hmm, you have a QT, so the drive shaft will still have an angle. It may still work. but really, two shims cost what, ten bucks? Just get ones with centering pins and you will be fine.
I just don't have time to mess with u bolts right now. If it's as simple as taking out two bolts and putting them back in a different position then great.

If it's an all weekend project I'll just deal with the tail dragger stance until the 74 isn't my only ride. And once it's semi-retired I'll get some new rear springs.
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Stuka »

You can drive it without the shims, I did for some time. But I did get some vibes at around 55, and u-joints only lasted about 6 months (drove it that way for about 2 years actually).
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Re: Post mount shackle reversal. Will I need degree shims?

Post by BRUTUS »

Nikkormat wrote:I could go to a ten inch lift and be Brutus height.
This is my vote!

EDIT: I wouldn't do the shackle reversal if I were you anyways. Much more fun to deny Blake's "faulty wheeling science" and say that you just don't want to bend new springs like the Honcho does! LOL
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Re: Post mount shackle reversal. Will I need degree shims?

Post by Nikkormat »

The funniest thing to me about Blake's shackle reverse is that mere months before he talked me out of doing a shackle reverse. And then he talked himself into doing it. And he still bends leaf springs!

Tad has a spring over and a shackle flip kit for 74-75 Jeeps now that converts to later full-size springs on the rear. All I really want is more flex and a smoother ride so taking the stock leafs from the 91 and putting them on the Cherokee would be perfect. With an end result something like this: Image
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