Rear Spring Questions

[kevinr1970]

I tried to use the search, but I didn't find the answer I was looking for.

I have an '82 K5 2wd.
I also have an '86 1/2 ton long bed 4x4, that has has 2" lift springs on the rear.
Would these springs directly bolt on to my K5?

I know that there are at least two different spring lengths (52" vs. 56"?). What I do not know is, is this a 1/2 vs. 3/4 ton difference or can a 1/2 ton have either? Or is it 2wd vs 4x4??
What are the ins and outs of the different rear springs???


As an aside, before going to bags on his 78 K5 Blazer, Trav used stock later model ('92+) K5 (K1500?)/2-door Tahoe rear springs and a flip kit to get ~3" or rear drop; the newer model springs sat higher (like a lift spring) so the filp kit netted 3" instead of the 5"+ it would normally get.
I only want to lower mine ~3" and the springs on the '86 longbed are less than 10 years old.
Anyone have any reason this wouldn't work provided the spring length is the same?

[nbpro]

http://67-72chevytrucks.com/vboard/s...d.php?t=359363

[westofb]

If I were guessing (I am guessing, don't mess with the 4x4 stuff) the 4x4 springs will have more of an arch to them than the 2wd springs would have. Thus, if you used them (assuming they are the same length) and then did a filp kit, you would not get your blazer as low as you would if you left the 2wd springs in it.

[kevinr1970]

Originally Posted by westofb

If I were guessing (I am guessing, don't mess with the 4x4 stuff) the 4x4 springs will have more of an arch to them than the 2wd springs would have. Thus, if you used them (assuming they are the same length) and then did a filp kit, you would not get your blazer as low as you would if you left the 2wd springs in it.

Yes, but that is what I am after
I am putting this on my 2wd K5.
I don't want to go crazy on it, so 3" would be just about right. If I understand right, a flip is good for 5-6" depending on spring leaf counts.
3" rear with 2.5" spindles and new springs all around should have it driving nicely!

[westofb]

I don't know how you would find out what kind of drop this would give you without actually putting everything in place and seeeing what happened. You could measure how far the top of your current spring sits from the bottom of the frame (at ride height with normal load on the spring), and measure the donor truck in a similar manner and you could see how more arch are in the springs. However, your truck is a blazer and the donor is a truck, so they will have different loads on the rear springs, you would not be comparing "apple to apple" more like apple to grapefruit..lol. I would think the blazer would be a little heavier on the rear springs than the truck, but probably not a great deal heavier...measuring the distance between the spring and frame should give you a rough idea on what the drop should be, most flips I have done are usually in the 6" drop area.

[USSkoval]

1. Both trucks PROBABLY have 52 inch springs. 56's were generally on 3/4 tons and several 1/2 ton Burbs.

2. 2wd and 4x4 rear springs have the same arch, not counting variations between different leaf packs and options. 4x4's got their extra height in the rear from taller spring hangers.

[kevinr1970]

OK, so I went out and measured. I hope this makes sense?!?

The long-bed 1/2ton springs ('86):
52" i-2-i, 5 leaf plus the short/flat/thick leaf (overload?) so 6 total - the 5th leaf is about the same length as the 6th (overload?) leaf but matches the arch of the rest of the pack. It is not as thick as the 6th leaf, but thicker than the rest of the pack

My K5 springs ('82):
52" i-2-i, 4 leaf plus the short/flat/thick leaf (overload?) so 5 total - the arch of the pack as a whole is a lot flatter than the 1/2ton long-bed pack.
It occurs to me that since the springs on the long-bed are less than 10years/under 10k, it might just be that the springs on the K5 are just "flat" worn out... literaly.

To confuse myself even more, my short-bed 1/2ton springs ('87):
56" i-2-i, 5 leaf plus the short/flat/thick leaf (overload?) so 6 total - the 5th leaf although shorter than the 4th leaf doesn't appear to be out of line with the progressive shortening of the leafs and matches the arch of the rest of the pack. The frame does have the holes there so I could move the rear shackle perch in and run the 52" springs.


I guess I should just put a flat edge across the eyes and measure down to the top of the spring pack. If the flip kit (5-6") minus that difference works out to ~3" lower than I am at now then I should be golden, right.........