One-ton leaf springs stock vs 63 inch.

[Jackson Hanes]

I'm in the early stages of my one ton swap and all the threads on this are outdated and just not helpful.

Planning on 3 link the front but would like to leave the rear leaf springs. But the stock springs are firm and unpleasant.

Does anyone here have a 63 inch leaf spring swap write up or at least some detailed pictures? Or just some wisdom

Would go crazy linking but I'm a broke apprentice.

 

[GLTHFJ60]

You're saying that the dozens, if not hundreds, of threads documenting a Chevy 63" swap are *unhelpful*?

You haven't even given us what truck you're working on, lol

 

[Jackson Hanes]

You're saying that the dozens, if not hundreds, of threads documenting a Chevy 63" swap are *unhelpful*?

You haven't even given us what truck you're working on, lol

Working with a FJ40 frame, 5.3-nv4500-241dhd

And yes the threads from 15 years ago are lackluster.

It was more of a inquiry seeing if anyone has a more documented thread.

 

[peesalot]

My 2 cents, with that drivetrain and a fj40 frame stock length, definitely 63's and you will want to make custom rear hangers ( pretty much shckle under bumper, aka, way back) to get wheel base or if you are keeping it stockish wheel base with a shorty drive shaft I would offer stock or lifted springs would keep travel within drive line tolerance and shorter wheel base. Stiff wise, how much junk you carry, 63's for a loaded 40 for a week of camping are decent with truck loaded.

 

[Jackson Hanes]

My 2 cents, with that drivetrain and a fj40 frame stock length, definitely 63's and you will want to make custom rear hangers ( pretty much shckle under bumper, aka, way back) to get wheel base or if you are keeping it stockish wheel base with a shorty drive shaft I would offer stock or lifted springs would keep travel within drive line tolerance and shorter wheel base. Stiff wise, how much junk you carry, 63's for a loaded 40 for a week of camping are decent with truck loaded.

Yeah, that's what I'm going to run into I think if a packaging issue. Already worried about rear shaft being to short. When you say move them way back are you talking something like this?

If I'm not mistake i have to makeup 14-15 inches of room for 63’s to fit?

 

[peesalot]

well that pic is a front but yes, thats the idea. I dont recall if you have to move front hanger to get 63's to fit. I do know that you can get 100 inch wheel base but requires cutting body. The 241 is strong enough but dont they have a LONG tail housing ? maybe it gets eliminated or switched to a fixed yoke. My 6.0, sm420, orion is as long as your 5.3 & 4500, my rear dline is like 25" , with that 241 yours is gonna be IMO approx at a max 12 ".

 

[EWheeler]

I think 63's are way too long for a 40 that isn't frame stretched. Here are some photos of my stretched wheelbase 40 with FJ60 rear leafs that were flipped, look at the photos in the first post at the linked page.

The Asian Mistress 40 Build

Time for a new build in the Cruiser section! I have been working on my 40 over the past two years and I am finally getting to the point where I feel confident enough to take it out and beat on it a bit. I started out my 40 adventure over on MUD, but now primarily spend most of my time...

www.pirate4x4.com

Internet says these are about 47.625" eye to eye leafs, here is eye to center pin dimensions:

• Measures (A/B) = 22-1/4" x 25-3/8"

I just don't see how 15 more inches of leaf spring would fit if you don't extend the rear frame and also move the front hanger forward. You'd likely have to mount the front hanger completely outboard of the frame to get desired ride height, if you mount it under the frame where it is flat, it's really going to lift the truck up high.

If you want longer leafs than FJ60 rears, I've read that there are some 54" packs out of either a tahoe or a dodge (dakota or durango?) that work good for extending wheelbase and getting more compliant ride and good flex. .

 

[Jackson Hanes]

well that pic is a front but yes, thats the idea. I dont recall if you have to move front hanger to get 63's to fit. I do know that you can get 100 inch wheel base but requires cutting body. The 241 is strong enough but dont they have a LONG tail housing ? maybe it gets eliminated or switched to a fixed yoke. My 6.0, sm420, orion is as long as your 5.3 & 4500, my rear dline is like 25" , with that 241 yours is gonna be IMO approx at a max 12 ".

Yes the 241 is long, and I agree it should hold up just fine. I bought a slip yoke elim kit but even then it is miles longer than a 205 for example.
And yeah I got greedy with the 4500
And 241 but I wanted an overdrive.

 

[Jackson Hanes]

I think 63's are way too long for a 40 that isn't frame stretched. Here are some photos of my stretched wheelbase 40 with FJ60 rear leafs that were flipped, look at the photos in the first post at the linked page.

The Asian Mistress 40 Build

Time for a new build in the Cruiser section! I have been working on my 40 over the past two years and I am finally getting to the point where I feel confident enough to take it out and beat on it a bit. I started out my 40 adventure over on MUD, but now primarily spend most of my time...

www.pirate4x4.com

Internet says these are about 47.625" eye to eye leafs, here is eye to center pin dimensions:

• Measures (A/B) = 22-1/4" x 25-3/8"

I just don't see how 15 more inches of leaf spring would fit if you don't extend the rear frame and also move the front hanger forward. You'd likely have to mount the front hanger completely outboard of the frame to get desired ride height, if you mount it under the frame where it is flat, it's really going to lift the truck up high.

If you want longer leafs than FJ60 rears, I've read that there are some 54" packs out of either a tahoe or a dodge (dakota or durango?) that work good for extending wheelbase and getting more compliant ride and good flex. .

Thank for the link, some good photos there. And yes I think 63s without a stretch is out of the picture. I'll look into some fj60 springs.

I'm not sure how deep I want to go, thank you for the input!

 

[EWheeler]

Thank for the link, some good photos there. And yes I think 63s without a stretch is out of the picture. I'll look into some fj60 springs.

I'm not sure how deep I want to go, thank you for the input!

54" Tahoe rear leafs with leaf spring sliders instead of shackles:

Post in thread 'Sliders'

Jul 17, 2024

This 40 has them up front:

Build - Frog's 40

forum.ih8mud.com

There is an ex-member here (got pissed off, threw a fit, deleted all of his stuff from the forum) that had them front and rear on an FJ55 with 54” springs from the rear of a 99 GM Tahoe SUV, and claimed it rode like a cadillac.

This is his truck in this thread:

CA - Liquid Iron Industries leaf spring sliders

Title is it. What have you got on the shelf for that project you changed your mind on? PM me a cost shipped to Georgetown, CA. I can come off hill to Auburn or Placerville sides. Since everyone likes in use photos:

irate4x4.com

Two benefits I see to them:
1. Lower ride height
2. Protect from bending a leaf spring by bashing it into

Downside I see...

• EWheeler

 

[Jackson Hanes]

Here is my current setup
Last night I was messing around in the shop and this is where I'm at.

I ended up with 56 inch springs
That metal on there is showing a 30 degree angle

Top is mine, red one is a reference

 

[Jackson Hanes]

So I got my hangers cut off now the problem I’m running into it how to make sure they’re actually square any tips?

i’m sure my eyeballs aren’t that good too eye them

 

[peesalot]

Move the front fixed hanger further forward, center bolt right between those rivets, grind them flat or drill the hanger and weld to the rivets as well. This will make that rear stick out of shackle much better.
For square I would pull tape off the crossmembers.

 

[DangerNoodle]

Make sure your frame is square and pull from a known location. I also like to use a straight edge across all the faces of the perch to make sure they are fully aligned.

 

[Jackson Hanes]

Move the front fixed hanger further forward, center bolt right between those rivets, grind them flat or drill the hanger and weld to the rivets as well. This will make that rear stick out of shackle much better.
For square I would pull tape off the crossmembers.

I actually intended in moving it back a little more because my the transfer case extended my driveline length more than I wanted.

I mean even where it is at now my driveshaft will maybe be 2-2.5 ft

 

[Jackson Hanes]

What do we think of this shackle angle? 27.5.

 

[Firemedic831]

We as in Me think it looks like s*** . and you do not even have the Body on yet or anything else that will make it even worse .

 

[Jackson Hanes]

We as in Me think it looks like s*** . and you do not even have the Body on yet or anything else that will make it even worse .

Fair enough, I didn't really have a choice I had to move everything back to accommodate the new driveline. I think by the time the quarters get trimmed it won't look awful.

 

[boots4]

Shackle has too much angle. You will not get the full benefit of going with longer springs at that angle. It needs to be more upright like closer to 45 degrees on your angle finder. Currently the spring rate could end up too soft.

 

[Firemedic831]

Fair enough, I didn't really have a choice I had to move everything back to accommodate the new driveline. I think by the time the quarters get trimmed it won't look awful.

I think you missed the point . your shackle angle is not good , and is going to be even worse when you add weight .