K20 lift springs on a ccdrw k30 to inprove ride?

[Tex_50613]

here's my thoughts and question, I want to improve the ride quality on the 85 K30 ccdrw I'm building, the truck is getting a 7.3l IDI international and a ZF5 trans backed by a NP205 divorced so the motor and drivetrain would be similar in weight to a 454ci bbc and a sm465 backed by a np205, my thoughts was to use a 3" or 4" suspension kit for a standard cab lwb K20 with new rear springs instead of blocks and a set of airbag helpers so as not to lose load capacity in the rear being as I plan on pulling a 32' tri-axle deck over bumper hitch with 2 mud trucks on it.
already knowing the spring widths are different am I off in my thinking that the K20 springs would improve the ride of the heavy rig when empty or is there a better option without going air ride?

[Dieselwrencher]

Why do you think the K20 spring widths are different? All the 73-87 GM ones I have seen are 2 1/2". The biggest difference I can think of in K20 and K30 springs is the K30 would have more leafs in the pack. As for the rear use a front leaf spring hanger from a 2wd chassis. Put this in the rear of your rear spring and do a shackle flip. I'd replace the shackle with a heavier unit though. No blocks and = about 4" of lift with a stock shackle. In the front I'd think the 4 leaf K30 springs will be fine for you. I have a few cummins chevy trucks running around with3 and 4 leaf front springs and they work fine. Sway bars are going to help a ton while towing, and air helpers in the rear will help as well. Especially with a bumper pull trailer.

[GCncsuHD]

Originally Posted by Dieselwrencher

Why do you think the K20 spring widths are different? All the 73-87 GM ones I have seen are 2 1/2". The biggest difference I can think of in K20 and K30 springs is the K30 would have more leafs in the pack. As for the rear use a front leaf spring hanger from a 2wd chassis. Put this in the rear of your rear spring and do a shackle flip. I'd replace the shackle with a heavier unit though. No blocks and = about 4" of lift with a stock shackle. In the front I'd think the 4 leaf K30 springs will be fine for you. I have a few cummins chevy trucks running around with3 and 4 leaf front springs and they work fine. Sway bars are going to help a ton while towing, and air helpers in the rear will help as well. Especially with a bumper pull trailer.

I think maybe meant by the spring width, was actually the distance between the perches? Other than that the difference just being the number of leafs, and the length of the springs. That is the one difference between the K10, K20, and K30 leafs that will determine fitment, K10s would all have 52" leafs, K20 can have 52" or 56" leafs, and K30 will have 56" leafs, so be sure to get the 56" leaf version.

The shackle flip is a good idea, and if you want a easy prebuilt bolt on kit or if you can't find the front leaf hanger to use, I have been thoroughly happy with my ORD shackle flip on my 01 2500HD. This will keep the ride MUCH better than lift springs, while not having the leverage of blocks to cause axle wrap. Compression shackle setups are also known to be more flexy, which can be good, but will also cause a little more sag when towing, shouldn't be an issue with your helper bag setup. Combining the shackle flip with removing a few leaves from the 1 ton setup along with the helper bags should yield the ride and towing ability you need.

Stronger shackles are a good idea, as the stock shackles are known to be weak, and since they are now a compression shackle rather than a tension, they will be subject to more leverage. An easy to come by alternative here would be 2" drop shackles, which when used with the shackle flip actually lift another 1-2" depending on which hole you use. Some are just stamped steel like the stock shackles, but there are some out there that are made out of heavy plate and nice welded construction, along with nice poly bushings. You can usually pick a set up for around $40-50 whereas places like ORD sell a similar shackle for over $100. An example, my Western Chassis brand drop shackles I had on my 03 were 1/4" plate with poly bushings, I only paid $40 for them brand new.

[Tex_50613]

the front springs on my ccdrw K30 are 3" wide where as the front springs on my K20 are 2 1/2" wide, from my research and looking at ordering taller lift springs for the K20 they are all that way.
As for the shackle flip in the rear I have that done on that my K20 which is making it harder to order the lift that I want being as I'll have to order fronts for 1 lift and a separate springs for the rear, with the cc I just want to order a all spring (no blocks) lift kit without having to piece it together in the future if I decide to go bigger.
and no mater what the truck is getting the air helpers mainly cause I have them but secondly because it gives me a excuse for a on-board air system on my tow vehicle, lol

[Dieselwrencher]

Do you have any pics of the spring being 3" wide? How can you get the springs mounted to the D60 if they're 3" wide? They only have 2 1/2" or room between the bolts and the u-blolt. My D60 is from a 88 V30 and it had 2 1/2" wide front springs and rear. The truck was a cc lb drw. Everyone I've seen has always had 2 1/2" wide springs. Fords have 3" springs and I've tried using fors springs on a chevy D60 and it wouldn't work without building a new way to secure the spring to the housing.

So how big of a lift do you want to end up with on this truck? Ordering the lift kit isn't that hard even with a shackle flip in the rear. Get a new stock spring and if you need an inch, get a leveling spring for it. Then pick your front spring. Can you take a pic of your front springs in your truck as well? I'd like to see them if you don't mind.

[GCncsuHD]

I would have to check mine, but I am 99% sure they are 2.5" wide. The only 3" springs I can think of off the top of my head are Ford 3/4-1 ton springs.

[Dieselwrencher]

Here is a description from Husky Spring's site. It shows the springs they offer. The first is for 1 tons 73-91.
http://www.huskyspring.com/K30-4WD-F...987_c_678.html

Note they are all 2 3/4" width.

73-87 3/4 ton K20's
http://www.huskyspring.com/K20-4WD-P...987_c_671.html

They are listed as 2 3/4" as well. (Which it should really be 2 1/2".)

For what it's worth I've swapped K20 and K30 front springs time and time again. Plus, not many places sell a lift spring for the K30's. My 12" lift springs were for 73-91 K20's and K30's.

[Tex_50613]

stock springs on the front of my ccdrw k30



4" lift springs on the front of my K20


stock rear springs on my K30



also 4 wheel parts told me about the front spring width differences between the K20 and K30 when I called to price out springs

[Dieselwrencher]

Well shoot I stand corrected. But you can still put the 2 1/2" wide front springs in your truck with out any issues. I have them in mine, always have.

[c Terris]

Originally Posted by Dieselwrencher

Well shoot I stand corrected. But you can still put the 2 1/2" wide front springs in your truck with out any issues. I have them in mine, always have.

Hey I have the same setup on my k20. 3" on the front and 2-1/2" on the rear. I'll go one step further and say that mine was supposedly a special edition or something from the factory. A factory plow truck. It also came with a 1 ton rear axle and a corporate 10 bolt front. I'm doing a shackle flip on the rear and want to do a 4" lift spring in the front. The tricky part is the mounts on the chassis are built for specific width springs. My mounts are a little less than 3", with bushings they are 3". Does anyone know what lift springs to use or how to convert the leafs to 2-1/2".