Need second opinion on leaf springs

[2kwik4u]

If I buy this leaf spring

https://www.etrailer.com/Trailer-Leaf-Spring-Suspension/Universal-Group/SP-111275.html

and this hanger kit

https://www.etrailer.com/Trailer-Leaf-Spring-Suspension/Redline/APS5.html

The problem is the shackle link would lower the attachment point of the leaf spring. For example, on the picture below, these 2 dimensions need to be equivalent. Therefore I would need to replace the front hanger to a longer hanger. And raises the trailer roughly 3-1/8" (the length of the shackle link). I think at that point, I would have to move the axle to above the leaf spring to maintain factory geometry.

View attachment 180045

The axle can be on top or below that leaf. Load doesn't really matter.

The only geometry you need to maintain is a level frame assembly.....just move the ball on your truck up a bit and you should be good.

 

[I_squared_r]

Maybe i'm going to do this. I found shorter galvanized shackle straps at 2-1/4" so its not too drastic of a geometry change. https://www.etrailer.com/p-18-11GALV.html About $200 total for everything and the double eye spring will be quieter.

What I don't understand is how the shackle straps pivot when tightened, but I saw a youtube video saying not to over tighten them.

 

[2kwik4u]

Maybe i'm going to do this. I found shorter galvanized shackle straps at 2-1/4" so its not too drastic of a geometry change. https://www.etrailer.com/p-18-11GALV.html About $200 total for everything and the double eye spring will be quieter.

What I don't understand is how the shackle straps pivot when tightened, but I saw a youtube video saying not to over tighten them.

Ideally you have a rubber bushing in there that allows the shackle to pivot and NOT rattle at the same time.

 

[I_squared_r]

I sketched the shackle links so I could get a visual how adding 2-1/4" or 3-1/2" shackle links to my OEM rear hangers would impact geometry. If I level the trailer at the tongue then the leaf spring would be rotated 6 and 8 degrees. I feel like that's not ideal, ride poorly, and accelerate wear on the spring. This is because the force now is being applied 6 and 8 degrees to the spring. I see the installation manual for shackle kits are very specific to avoid this situation. For example, for a 25-1/4" eye-to-eye spring, a company sells a kit with 3-1/4" tall front hanger, 1-1/4" tall rear hanger, 3-1/8" shackle link, and install 24-7/8" between hangers. The 1/8" precision on their installation is a little alarming to me because their engineers decided that precision is necessary to proper installation of a double eye spring.

I plan on taking the boat into NYC and launching there so I need a trailer that can survive NYC roads. So I ordered the original shorelander springs from a small local dealer $210+tax+shipping. A woman answered and she was very knowledgeable. She said Shorelander is generally expensive and they recently increased their prices a lot because they do small volumes and the price of metal has increased. I kind of expected that. Well, the good news is that I will have a "new" trailer with new brakes, springs, tires, lights, wiring, and I can feel safe going on longer trips this year. The bad news is that it probably cost me around $1000. ?‍