Offset shackles

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bwillaub

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How much more room do these give you for wider tires? Who is a good source for them? Thanks.
 
They offset the springs a 1/2”, so that’s what you get. DoctorDiff’s are nicer than the Mopar Performance version, which claims it’s a 3/4” offset. Which isn’t true. The front hangers can only be offset a 1/2” before they hit the frame rail in the front. So on the MP kit the hangers are offset a 1/2”, the rear shackles are offset 3/4”, and you put a 1/4” worth of bind on the springs.

The doctordiff kit uses better hardware, so you don’t have to cut a hole in the frame rails for clearance like you do for the MP kit.
 
I have the Dr Diff ones on my duster, they are a good quality.

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That’s a great view of the doctordiff hardware. Shows exactly why the Mopar Performance kit can’t be a 3/4” offset.

Not entirely so , I had to dimple the frame and eggshape the holes in my car to get the front ones in (w/ a hammer(> almost 3/4" .
I bought them off a member on here , that said they wouldn`t work on his car. I got no idea who made them tho . I have 295 65 15 drag radials on a 68 barracuda fast back using them with the standard tricks.
I bougth a complete reworked dana 60 w/ a Detroit locker in it, set up 1" narrower than stock, w/ disc brakes. Couldn`t pass up the deal back then. The builder welded the spring pads in exactly 3/4" narrower than a stock A body, it dropped right in using no prying or pushing the springs and is centered perfectly.
Stil lneed bigger tires tho---
Wish I could post pics on here but some reason I can`t .
 
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Not entirely so , I had to dimple the frame and eggshape the holes in my car to get the front ones in (w/ a hammer(> almost 3/4" .
I bought them off a member on here , that said they wouldn`t work on his car. I got no idea who made them tho . I have 295 65 15 drag radials on a 68 barracuda fast back using them with the standard tricks.
I bougth a complete reworked dana 60 w/ a Detroit locker in it, set up 1" narrower than stock, w/ disc brakes. Couldn`t pass up the deal back then. The builder welded the spring pads in exactly 3/4" narrower than a stock A body, it dropped right in using no prying or pushing the springs and is centered perfectly.
Stil lneed bigger tires tho---
Wish I could post pics on here but some reason I can`t .

Believe whatever you like, but there’s only a 1/2” of space between the front hangers and the frame rail. Unless you put the whole inside wall of the hanger inside the frame rail, it’s not a 3/4” offset.

The MP hangers require dimpling or cutting a hole in the rail to clear the nut welded on the hanger for the spring eye bolt, but it still doesn’t get you to 3/4” in the front. I used those hangers on my Duster, if you hold them up against the doctordiff hangers the offset is identical and it’s a 1/2”.
 
If you cut the overlapped flange in the corner, you can get another 1/8" or so. Either way, it's splitting hairs. Considering the tolerances these cars were built to from the factory 3/4" is the same thing as 1/2" in my book.
 
tirely so, I had to dimple the frame a little and drill
Believe whatever you like, but there’s only a 1/2” of space between the front hangers and the frame rail. Unless you put the whole inside wall of the hanger inside the frame rail, it’s not a 3/4” offset.

The MP hangers require dimpling or cutting a hole in the rail to clear the nut welded on the hanger for the spring eye bolt, but it still doesn’t get you to 3/4” in the front. I used those hangers on my Duster, if you hold them up against the doctordiff hangers the offset is identical and it’s a 1/2”.

I guess u need to come look at and measure mine, I`m very glad u know more about how I installed them and what it took to get them in there than I do. As much diff. as there is in these old non computer designed cars, there could be light worlds of diff. in the bodies. But of course u know more about my car than I do !!
Where were u when I needed to buy all the parts for a total basket case !
 
If you use the Mopar kit the springs end up at angle with some spring bind, if you do have that kit l would take some offset out of the shackles with a press or hammer if you like hitting stuff...get the springs in straight and weld on the spring pads last.
 
tirely so, I had to dimple the frame a little and drill


I guess u need to come look at and measure mine, I`m very glad u know more about how I installed them and what it took to get them in there than I do. As much diff. as there is in these old non computer designed cars, there could be light worlds of diff. in the bodies. But of course u know more about my car than I do !!
Where were u when I needed to buy all the parts for a total basket case !

Your car isn’t off by a 1/2” at the frame rails, I’d almost guarantee it. And before you say anything, if both sides are off by a 1/4” then yes, that means the frame rails are off by a 1/2”.

Suspension points were held within a 1/4”, and that means at most you might get 5/8” and that’s still not likely. Or one side would fit but not the other. I’ve got two ‘71’s and a ‘74, all from different factories. The frame rails and suspension points are damn near identical for location. The bodies vary a bit, but the suspension points are much more accurate.

I’ve measured the hangers. Stock hangers, MP “3/4” hangers, Doctordiff hangers. They all have a 1/2” offset. I measured all of that stuff before I installed my spring perches so I wouldn’t put any bind on the springs, because Cass told me exactly what I’ve been saying- the MP hangers only have a 1/2” offset because that’s all the space there is. Even if your car was totally screwed up, MP didn’t make the hangers for your car, they made them to fit all of them. The only thing with a 3/4” offset in the MP kit is the shackles, and that puts a bind on the springs.

But my all means, break out a tape measure and take some pictures. If you provide evidence that shows your car is somehow some special unicorn and your spring hangers are custom made to take advantage of that then I’ll believe you. Until then though I’m just going to assume you believed the MP hype and put a bind on your springs when you offset the perches 3/4” instead of the 1/2” that the hangers really have.
 
I am going to go out on a limb here and say that Dr diff's kit is 1/2" front and rear, or whatever is needed to keep the leaf springs at the correct angle. I also got a measurement from him for center to center distance on the new spring pads i got as well as they needed to be moved inward.

72bluNblu are the rear leaf springs tapered at all front to rear, or are they square with everything? Mine look to be square as i have the same 1" clearance from the spring to the tire front and rear of the tire.
 
My 69 Valiant with Mopar off set kit, you can see how the spring is ginked in the picture....been meaning to fix it, it’s only been like that since the late 90’s...

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I am going to go out on a limb here and say that Dr diff's kit is 1/2" front and rear, or whatever is needed to keep the leaf springs at the correct angle. I also got a measurement from him for center to center distance on the new spring pads i got as well as they needed to be moved inward.

72bluNblu are the rear leaf springs tapered at all front to rear, or are they square with everything? Mine look to be square as i have the same 1" clearance from the spring to the tire front and rear of the tire.

A-body springs are parallel to the frame rails, no taper front to rear. And the DoctorDiff offset kit for A-bodies is a 1/2" offset front and rear, the springs stay parallel.

The Mopar Performance offset kit has a 1/2" offset on the front hangers and a 3/4" offset on the rear shackles, and is advertised as a 3/4" offset. If you put the spring perches at a 3/4" offset, you put a bind on the front half of the spring (and you still don't get a full 3/4" of tire clearance). If you put the perches at a 1/2" offset, you put a bind on the rear half of the spring. The only way to not put a bind on the spring would be to set the hangers and shackle mounts at an angle to match the offset, so the springs would be angled and everything would be inline (eye bolts and shackles would be parallel to the springs, but the springs wouldn't be parallel to the frame). But that would set up an angle opposite of what you usually want, if the rear springs are splayed it's done so the fronts are narrower than the rears. E-bodies have splayed springs, the front is narrower than the rear. Like anything with suspension there are pros and cons to doing that way.

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A-body springs are parallel to the frame rails, no taper front to rear. And the DoctorDiff offset kit for A-bodies is a 1/2" offset front and rear, the springs stay parallel.

The Mopar Performance offset kit has a 1/2" offset on the front hangers and a 3/4" offset on the rear shackles, and is advertised as a 3/4" offset. If you put the spring perches at a 3/4" offset, you put a bind on the front half of the spring (and you still don't get a full 3/4" of tire clearance). If you put the perches at a 1/2" offset, you put a bind on the rear half of the spring. The only way to not put a bind on the spring would be to set the hangers and shackle mounts at an angle to match the offset, so the springs would be angled and everything would be inline (eye bolts and shackles would be parallel to the springs, but the springs wouldn't be parallel to the frame). But that would set up an angle opposite of what you usually want, if the rear springs are splayed it's done so the fronts are narrower than the rears. E-bodies have splayed springs, the front is narrower than the rear. Like anything with suspension there are pros and cons to doing that way.

View attachment 1715247242
A-body springs are parallel to the frame rails, no taper front to rear. And the DoctorDiff offset kit for A-bodies is a 1/2" offset front and rear, the springs stay parallel.

The Mopar Performance offset kit has a 1/2" offset on the front hangers and a 3/4" offset on the rear shackles, and is advertised as a 3/4" offset. If you put the spring perches at a 3/4" offset, you put a bind on the front half of the spring (and you still don't get a full 3/4" of tire clearance). If you put the perches at a 1/2" offset, you put a bind on the rear half of the spring. The only way to not put a bind on the spring would be to set the hangers and shackle mounts at an angle to match the offset, so the springs would be angled and everything would be inline (eye bolts and shackles would be parallel to the springs, but the springs wouldn't be parallel to the frame). But that would set up an angle opposite of what you usually want, if the rear springs are splayed it's done so the fronts are narrower than the rears. E-bodies have splayed springs, the front is narrower than the rear. Like anything with suspension there are pros and cons to doing that way.

View attachment 1715247242

Well since u know every thing about every part made for every mopar, maybe u can tell me who made mine !
Some people !
 
Dr.diff kit is nicer, I've used the mp and dr.diff, the problem with the dr.diff kit, it's been out of stock for a long time. 6 months, a year, I don't know. Every time I emailed him i got The same story, New fabricator making them, they'll be available in a couple weeks.

The mp kit is funny, I bought a set off a guy since I couldn't get the dr diff ki, I don't remember this with my last one I used, but the front spring eye bolt is offset toward and up. I don't know if they used to sell different ones but I'm thinking these were designed for ss springs.
 
Dr.diff kit is nicer, I've used the mp and dr.diff, the problem with the dr.diff kit, it's been out of stock for a long time. 6 months, a year, I don't know. Every time I emailed him i got The same story, New fabricator making them, they'll be available in a couple weeks.

The mp kit is funny, I bought a set off a guy since I couldn't get the dr diff ki, I don't remember this with my last one I used, but the front spring eye bolt is offset toward and up. I don't know if they used to sell different ones but I'm thinking these were designed for ss springs.
I might have mine for sale if I decide to go ahead and mini tub it , IF , I can get them out w/o destroying anything.
And. my springs deo hang level and not cocked at all.
Same distance c to c , front and rear.
 
The new mfg dragged their feet, so I'm making the offset hangers in-house again. They are currently in stock.

Hey Doc - I just received mine earlier this week. Nice stuff for sure!
Thanks for the quick shipping.
 
Well since u know every thing about every part made for every mopar, maybe u can tell me who made mine !
Some people !

Well maybe if you'd post picture I could! But I'd bet money you've got an MP kit.

Bob, the bottom line is it doesn't matter who made your offset hangers. Unless you have a car that was built well outside of the factory specifications for your spring mounting and frame rail locations there isn't 3/4" of space to move the front hanger inboard before it hits the rails. I don't have to know everything about every part ever made, all I have to know is the chassis specs. And there isn't 3/4" of space there.
 
Well maybe if you'd post picture I could! But I'd bet money you've got an MP kit.

Bob, the bottom line is it doesn't matter who made your offset hangers. Unless you have a car that was built well outside of the factory specifications for your spring mounting and frame rail locations there isn't 3/4" of space to move the front hanger inboard before it hits the rails. I don't have to know everything about every part ever made, all I have to know is the chassis specs. And there isn't 3/4" of space there.
You must not read well, I don't know who made mine , and u evidently didn`t read or understand what I said I had to do to get them installed. The person I bought them from couldn`t even get them in his car. ????
That being said, I`m thinking about mini tubbing it anyway.
 
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