Anti-inversion shackle question (1 Viewer)

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I've been searching this forum and the web for awhile and am starting to get frustrated. I just got a 2.5" OME kit from Man-a-fre and they shipped everything but instructions :mad:! What is the correct orientation of the anti-inversion shackles? Anybody got a handy picture of the front and rear installation of the triangle style? Thanks in advance.

Bob :cheers:
 
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These are MAF but I think they go the same way

4589650135_07a3b29d68_b.jpg
 
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I placed my shackle in the rear opposite to the above thread.. due to the fact that if you look closely, the rear bracket and center bolt of the shackle are in the same position as in the front, so that the center bolt travel is restricted by its ability to be stopped by the bracket. If reversed, nothing can stop the center bolt travel. Mine is a MAF shackle. Don't know who is right or wrong or if there is a right and wrong??

71LandCruisernewtop.jpg
 
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I placed my shackle in the rear opposite to the above thread.. due to the fact that if you look closely, the rear bracket and center bolt of the shackle are in the same position as in the front, so that the center bolt travel is restricted by its ability to be stopped by the bracket. If reversed, nothing can stop the center bolt travel. Mine is a MAF shackle. Don't know who is right or wrong or if there is a right and wrong??..

Sorry. I can't understand your explanation for why you've done the rears as you have... but your front is correct and your rear is wrong.

Anti-inversion shackles are supposed to stop your rear shackles from being able to rotate so far foward (on their chassis-located pivot bolts) as to "lock-up" against your chassis rails (ahead of your "shackle-pivots"). .... and such a thing can tend to happen if you get airbourne for instance.

The way you've mounted yours - they can't perform this duty (that they were designed to perform).

:cheers:
 
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Re-visiting an old thread...

So I removed my springs, rear spring gussets and rear spring perches and now baffled over orientation of my OME anti-inversion shackles.

I kind of see texfj40's theory, see picture below.

The forward rear spring pin is fixed, therefore unable to travel in any direction. As the spring compresses it would seem the spring would be pushed back towards the rear of the vehicle, no?

Any more opinions?
Anti Inversion.jpg
 
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............................
The forward rear spring pin is fixed, therefore unable to travel in any direction. As the spring compresses it would seem the spring would be pushed back towards the rear of the vehicle, no?....

Quite right!

But the anti-inversion feature isn't required for protection during "spring compression" (when a wheel hits a bump). Instead it protects a leaf spring when it under very little (if any) compression load which usually occurs when the wheel closest to that spring is "hanging in the air".

In fact, "inversion" is most likely to occur (in a vehicle without anti-inversion shackles) from driving too fast over a hump so you become airbourne. And "inversion" is also more likely to occur when "at rest shackle angles" are wrong (close-to-vertical) which also happens to give a harsh ride (compared to correct shackle angles).

So the "anti-inversion feature" actually prevents a shackle from angling about its top pivot pin "so far anticlockwise" (in the case of the rear springs) or "so far clockwise" (in the case of the front springs) that the spring eye jams up there (against the chassis rail) when the load comes back on that spring. Edit...I'm imagining looking at the RIGHT-HAND side of your cruiser in saying this.

If someone has a photo of a spring stuck in this "inverted position" I think it would help this thread.

:beer:
 
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Josie'sLandCruiser

Stop calling it a "FJ."
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Hi All:

LostMarbales is correct! :beer:

Like he mentioned, inversion happens after the suspension has been fully unloaded, then suddenly is compressed. The shackle in question has extended in the negative arc so far it cannot recover.

I had this problem with stock-type shackles on the right-front shackle while doing rough off-roading. Switched to the 3-bolt type anti-inversion shackles and have not had this issue since.

Regards,

Alan
 

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