questions regarding leaf springs

[John Fabris]

I picked up a set of front/rear leaf springs from a friend.
It is possible that they are 6 inch lift leaf springs from a 67-72 truck.

Doing some research on converting my 68 3/4 ton panel to 4x4 using the fgb52 kit from diy4x.

question #1, when they say 52 inch springs, how is that measured? (spring eyebolts center to center? or lenth of spring itself including curve?)

question #2, is there a way to identify the spring lift?


Thanks!!!

[Blue_71]

on the measurment, im pretty sure it is measured from eye-to-eye (center to center)

im not sure how to tell how much lift it is, but the front springs are definately lift springs. stock springs have a negative arch to them. the rear doesnt really look like lift springs to me though

[desertrat]

Leaf springs are measured from center of eye to center of eye. The only way to get an accurate measurement of how much lift these springs have (in my opinion) is to measure them at ride height on the truck. But for the most part all the lift springs should have have the same arch unless you go with a custom spring.

Is it me or is this main leaf broken? If it is bent like the picture I would toss them into the scrape metal bin.

[Big-Blue]

The correct way is to measure it along the curve, center of eye to center of eye. It's not the straight measure eye to eye as it will change or vary with load, no load, sag over time, etc.

Many lift companies or spring companies have help sections on measuring this.

[msgross]

hmm, don't look like 6"... Almost looks like stock 3/4 ton for 4" 1/2ton ... That's just a guess though.

[John Fabris]

agreed that the one front spring is bent. but with teh diy4x fgb52 kit, I would be using the two rear springs on the front of the panel. did a search, and yes, found out that you measure from axle mounting point along the arc to each eye. Thanks guys!

[Yukon Jack]

Here's a pic of my 69 K20's stock front springs next to a 4" Tuff Country EZ Ride front spring.



I don't have a good pic to show that the stock spring would be negatively arched with the weight of the vehicle on it.

Comparing the front spring in your pic, sure makes it look like a 2" lift spring to me.

[Big-Blue]

You can see the negative downward camber in my front springs. I am sure they have sagged some since they were new too. Probably about an inch lower than flat horizontal.