How to identify where a shackle came from and if there is a lift incorporated. (1 Viewer)

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I've been more of a lurker than a contributor on this website but that's about to change. I have an FJ40 project that I picked up about a year ago. I'm finally getting started on diving in to finish this and get it back on the road. One of the questions I have with this rig is how to identify where the shackle reversal came from and is there a lift associated with it? Rear shackle is 5.25" center of bolt to center of bolt, front shackle is 3" center of bolt to center of bolt. Pivot points are greaseable. Front bracket is approx. 5.5" from underside of frame to center point of bolt at front of leaf spring. Any insight anyone may have would be appreciated.
 
Right.
Attached are photos of the front shackle.

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The shackle in the photos is definitely not stock, but it looks like stock length. How many inches (or mm) between the grease zerks? But I've never seen one like that; have no idea where it may have come from.

Edit: OK, I see where you said in the first post it was 3". Stock length is just under 3", probably closer to 2-3/4". The spec is in mm of course, but I don't remember off the top of my head how many. But anyway, that shackle is close to stock length - no lift from that.
 
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And the rear shackle pics. And a couple pics from when I picked it up last spring. It's a 1970 FJ40 - Body is in decent shape - bought it from a guy in Cali who I believe was the 8th owner....

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The shackle in the photos is definitely not stock, but it looks like stock length. How many inches (or mm) between the grease zerks? But I've never seen one like that; have no idea where it may have come from.
3" center to center on the front shackle.
 
3" center to center on the front shackle.

Thanks; see my edited post above.

Your rear shackles are longer than stock, looks like about 5-1/4"? which is about 2-1/2" longer than stock, which by itself would yield a 1-1/4" higher "lift" over stock. Most spring lifts (with longer leaves) can benefit from longer shackles. Pretty common to use longer shackles on the rear than on the front.
 
Those are not stk shackles. Imo. It appears to be lifted. Whats the tire size? I'm not real familiar with shackle reversal. I think they usually use 2" lift springs in the front and 4" in the rear. It could be stk spring too.
 
This is the old " advance handling" reversal kit , it lift the front 1.5" , this is why it need longer shackles in the rear

It was popular back in the mid 90 , and it was also sold by BTB , the trend was to use 4" lift spring in the rear and 2.5" in front to make it level , longer shackles in the rear is the other way to compensate
 
Those are not stk shackles. Imo. It appears to be lifted. Whats the tire size? I'm not real familiar with shackle reversal. I think they usually use 2" lift springs in the front and 4" in the rear. It could be stk spring too.
I don't see identification #'s on the leaf springs - front or back - I could be missing the #'s if not located in obvious place... Tire size as it sites is 30". I'd like to put either 33's or 35's on it eventually. I did just measure from top center of axle to bottom/top of frame - positioning was plumb and directly outside of the frame. Front dimension is 6" from top of axle to bottom of frame, 10" to top of frame. Rear dimension is 9" from top of axle to bottom of frame, 12" to top of frame. Not sure if this is a reliable method of comparison when assessing a lift... No shocks on this rig currently, just the leaf springs.
 
Was it mentioned the front is a shackle reverse which would actually moves to the shackle to the back side of the spring. Front is fixed and doesn't flex like a shackle does.
 
Was it mentioned the front is a shackle reverse which would actually moves to the shackle to the back side of the spring. Front is fixed and doesn't flex like a shackle does.
It wasn't mentioned but I'm up speed on that aspect. I included that picture as a reference when trying to identify the shackle reversal kit and it seems like there is a kit identified in the thread - which is great, I'll reach out to BTB to learn more about it.

As much of a newb as I am - I do have a little bit of wrenching, rewiring, fabrication and head scratching experience to draw from. I'm a timber framer/design build for residential construction kind of guy and have on old BMW tear down/rebuild mostly behind me. There are still a few things to do with it but I'll be riding it when the snow melts...

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Assuming stock leafs, you have a minimum 2” lift over stock with your current setup. This should allow 33x10.5 tires with little drama. If you go 33x12.5 you will likely have some rubbing in the rear wheel wells when articulating off road, but should be ok on road. Trying for 35’s will be tough for multiple reasons front and back.
 
Assuming stock leafs, you have a minimum 2” lift over stock with your current setup. This should allow 33x10.5 tires with little drama. If you go 33x12.5 you will likely have some rubbing in the rear wheel wells when articulating off road, but should be ok on road. Trying for 35’s will be tough for multiple reasons front and back.
Thanks for weighing in snaggletto. What would those reasons be on the 35" tire option? I'm not sure which size tire I'd go with but would appreciate the education either way.
 
It wasn't mentioned but I'm up speed on that aspect. I included that picture as a reference when trying to identify the shackle reversal kit and it seems like there is a kit identified in the thread - which is great, I'll reach out to BTB to learn more about it.

As much of a newb as I am - I do have a little bit of wrenching, rewiring, fabrication and head scratching experience to draw from. I'm a timber framer/design build for residential construction kind of guy and have on old BMW tear down/rebuild mostly behind me. There are still a few things to do with it but I'll be riding it when the snow melts...

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Not as far as steering but braking how would the bike handle if the front forks angle back not forward?
 

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