Difference in K10 and K20 Front Springs

[89Suburban]

Sit on the porch and wait for me, I'm almost there lol.

He can hold his breath too.

 

[bucket]

It's seeming to me that 70's trucks have three leaves in the front and 80's trucks have only two (but probably thicker) leaves in the front.

I took pics of the front springs in my '77 K5, I'll post them shortly.

 

[HotRodPC]

Sit on the porch and wait for me, I'm almost there lol.

Just for ***** & giggles I wonder what freight could be on those if strapped to a pallet. Maybe find a LTL carrier to bring it pretty cheap. Not like I am in a hurry for it, even if it took 2 weeks. Cuz I know you can use a nicely built trans. You know axles for tranny, tranny for axles???

 

[crazy4offroad]

I'll try to find out one day next week, I got a lot to do this week.

 

[GreaseDog]

Acuatually !!! aka Actually... I might be able to learn you something about that rear spring dimmensions as far as length. For whatever reason, depending on which RPO code and if heavy duty or not, C10 can have either 52 or 56 inch rear springs. The only other model can have either 52 or 56in springs is K20. So 2wd half ton, and 4x4 3/4 ton can be either from the factory. The rest are pretty much as you'd expect. K10 is 52in rear and C20 is 56in. So being that K20 can be either, I'm moving my K10 springs hangers and installing the C20 rear springs. Just seems to me that the C20 rear springs are going to raise the rear. So how does the front get raised to match in OEM. Is it in the shackles, spring height or what? I'm fairly certain 3/4 ton front K springs can be 2 or 3 springs depending on the RPO codes.

i have also seen what appeared to be a factory 52" 11 leaf pack that came off of my 81 K30 cab and chassis truck.

as for the front springs to match the rears, you can either to an add a leaf, or a zero rate in the front, depending on how much difference, and how much you want to correct it.

 

[HotRodPC]

i have also seen what appeared to be a factory 52" 11 leaf pack that came off of my 81 K30 cab and chassis truck.

as for the front springs to match the rears, you can either to an add a leaf, or a zero rate in the front, depending on how much difference, and how much you want to correct it.

For real? 11 pc 52in length and not 56??? I've seen the 11, but it was 56in.

I think one of my K trucks is going to end up with the 454 that is in the 84 C20, so I'll likely want to add a 3rd spring anyway for the added weight.

I'm thinking the 84 C20 is going to be the truck that gets the Olds 455 with the Variable Pitch Torque Converter Th400 using the motor mounts out of the 80GMC that originally had the Olds Junky 350 diesel. This way the motor, trans and all will be in the OEM positions, OEM crossmembers, driveshafts and all. Only thing I have to do the trans, is when I rebuild the Variable Pitch Th400, instead of the 9in long output shaft, I'll put the short output shaft that is threaded in the end for the bolt on yoke. The truck is already set up for BBC and Th400, so this Olds Powertrain swap should be nothing more than swapping the motor pads off the frame that came out of the 80 Diesel truck, and moving the starter wires to the drive side instead of the passenger side.

 

[bucket]

Here's my spring pictures I forgot about. Is it me, or are they identical to the K20 springs posted earlier?

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[HotRodPC]

Thanks Andy. Yes, it does look identical to the K20 springs earlier. Is this your K20 or K30? I'd almot like to compare K30 springs too. Then someone else has a K20 that is 2 springs and looks identical to my K10 and K1500. I'm still wondering what decides if you get 2 springs or 3 springs up front. I thought it might be big block gets 3, but the last K20 was small block.

 

[GreaseDog]

For real? 11 pc 52in length and not 56??? I've seen the 11, but it was 56in.

I think one of my K trucks is going to end up with the 454 that is in the 84 C20, so I'll likely want to add a 3rd spring anyway for the added weight.

I'm thinking the 84 C20 is going to be the truck that gets the Olds 455 with the Variable Pitch Torque Converter Th400 using the motor mounts out of the 80GMC that originally had the Olds Junky 350 diesel. This way the motor, trans and all will be in the OEM positions, OEM crossmembers, driveshafts and all. Only thing I have to do the trans, is when I rebuild the Variable Pitch Th400, instead of the 9in long output shaft, I'll put the short output shaft that is threaded in the end for the bolt on yoke. The truck is already set up for BBC and Th400, so this Olds Powertrain swap should be nothing more than swapping the motor pads off the frame that came out of the 80 Diesel truck, and moving the starter wires to the drive side instead of the passenger side.

i thought it was odd too, i was going to strip them down to 4 or 5 leaves, and install them in the rear of the K10 i was building at the time. opted to leave the stock 52s in it when i discovered they were also 52s.

the Olds 455 will be a fun one. i had a 73 C20 that was converted to a dually with a 455 Olds in it... fun truck!

 

[bucket]

Thanks Andy. Yes, it does look identical to the K20 springs earlier. Is this your K20 or K30? I'd almot like to compare K30 springs too. Then someone else has a K20 that is 2 springs and looks identical to my K10 and K1500. I'm still wondering what decides if you get 2 springs or 3 springs up front. I thought it might be big block gets 3, but the last K20 was small block.

Those are actually the original springs in my '77 Blazer. I still have the front springs from my '88 Burb (it used to be a K10) and I'm pretty sure they are only 2 leaves and the ends are shaped different. My K30 already had the lift springs when I bought it.

 

[HotRodPC]

Those are actually the original springs in my '77 Blazer. I still have the front springs from my '88 Burb (it used to be a K10) and I'm pretty sure they are only 2 leaves and the ends are shaped different. My K30 already had the lift springs when I bought it.

See, that's what I'm thinking too. It may just not matter, cuz I hope to do at least a 4in suspension lift, so I'll be replacing the springs anyway. I wasn't going to use blocks in the rear either, but If I put the C20 56in springs back there for the added strength and the comfort, I've been told 4in blocks aren't so bad at all. But how are the blocks going to be if I put a good trailer load on the truck? Is it still going to be safe and will the blocks hold up? If I was to have to replace both front and rear springs, I'd still want the 56 springs in the rear and I'd likley go with a 6in lift kit since the cost isn't alot between 4in and 6in in a full spring no block lift kit.
On one of my trucks, likely the nicer one that I don't want to be giving pure hell, I might even do the 56in C20 springs on 4in blocks, then do the 52in springs that I take off the rear, to the front moving the front spring hanger forward, and netting 4in lift in the front too. That should make for a comfy riding 4x4 with a 4in lift. 56in springs in the back on 4in blocks, and 52in rear springs on the front for 4in. Whadda you think about that idea anyone???

 

[89Suburban]

 

[crazy4offroad]

Screw the rear blocks, I would go shackle flip. It's too easy to do, and cheap. If you plan on pulling a heavy trailer, or heavy tongue weight trailer, I would do all spring lift rear. The blocks can break springs under heavy loads, and the shackle flip can bend the shackles under heavy lateral forces.

 

[HotRodPC]

Screw the rear blocks, I would go shackle flip. It's too easy to do, and cheap. If you plan on pulling a heavy trailer, or heavy tongue weight trailer, I would do all spring lift rear. The blocks can break springs under heavy loads, and the shackle flip can bend the shackles under heavy lateral forces.

I was afraid that would be the news on the weight. It won't be much really. My 18ft tandem trailer and a 2-3 ATV's if I do use the 4x4 for towing since if going out to off-road, I'd take my ATV's with me. I can use the C20 for the heavier towing like full size complete vehicles or taking left over bad parts to the crusher. So no, it won't be a extrememly heavy towing. Maybe 5000lbs with the weight of the trialer if I did a complete vehicle and about 3000lbs if just doing the recreation thing.

 

[bucket]

I have 56's and 4inch blocks under the rear of my '88 Burb and have pulled a bit of weight, as well as flexed it out pretty good a time or two. They are holding up fine.

Plus, the newer Dodge and Ford heavy duty trucks have 4 inch blocks in the rear right from the factory. If it's good enough for them, it's good enough for me.