1/2-ton to 3/4-ton...same spring width?

[truckmen]

Hello all,

I've just joined the forum and have a Question about the rear leaf springs. Having a 1500, can I upgrade to 3/4-ton leaf springs without having to change the hanger and brackets? In other words, are the two leaf spring the same width?

 

[Supercharged111]

The leafs will bolt right up no problem, but it'll only decrease rear squat under load. That POS 8.5" rear diff will still hold you back, as will the POS 4L60.

 

[truckmen]

Thanks, Supercharged111,

What could I replace the 8.5 with? And the current 350 engine is kinda weak anyway.

 

[99'Subourbon]

14b sf rear axle, from a HD 1500 so you can retain the 6 lugs. Otherwise you'll need to convert them over.

 

[Supercharged111]

Also found on the light 3/4 tons as they too had 6 lugs. Same axle. The beauty of it is that EVERYTHING is bigger. That plus its associated leaf pack increases the rear axle rating from 3600 to 4600 (on the LD 2500) and GVWR from 6200 to 7200. 6600 for the heavy half.

 

[LoneCynic]

As another poster mentioned before me, they will indeed bolt right up. I did this exact swap on my K1500. They bolted up and took very little time at all to install the 4+1 3/4 ton leafs on the truck. Where the problem lies is getting the old leafs off. Mine were an absolute nightmare, as the metal casings inside the bushings had corroded and I couldn't pull them off for anything. I ended up cutting them off, and using all new mounting hardware for the new ones. Make sure you get six of the bolts, and just get new shackles while you're at it too for the rear side of them. It will make things go a lot smoother than trying to reuse any of the old hardware. Everything else will be fine, the mounting brackets will line up fine, as will the u-bolts at the axle.

Getting the old leafs off is the problem, putting on the new ones is a breeze.

 

[Ironhead]

just want to second what LoneCynic says about getting new hardware. I've replaced leaf springs in another vehicle in the past, and part way through the job, put my tools down, and ordered all new hardware, bushings, etc. It was the only way to go.

 

[Supercharged111]

Depends on where the truck has lived it's life. Mine was and always has been a CO truck, really clean underneath. Never have I seen a seized fastener.

 

[LoneCynic]

Mine has spent most of its life in the midwest, Ohio and WV to be specific, so it wasn't unrealistic to expect that to happen. Even when I wash off the underside after driving it in road salt conditions, it easily could have gotten inside there and corroded like that over the course of 20+ years before I replaced the leaf springs.

 

[truckmen]

Hello all! Thanks to 99 Subourbon, Supercharged111, LoneCynic, Ironhead and all the readers for taking the time in submitting this valuable information. It's helping me a lot. Although recent financial constraints have impinged on my desire to upgrade the truck right now, I still want to go ahead and do it. This will take some time so in the meantime, I will hunt at yards for the parts and take the advice about new hardware for sure. Ralph