71 'Burban Suspension

[RyanAK]

Hey, gang. I have this posted up in the Suburban & Panels forum, but thought I might get some extra input here. I own a '71 C-10 Suburban affectionately named "Earl".





Well we've been having fun driving him around on short trips here in eastern New Mexico. Even got the factory, full-length roof-mounted A/C working for a while... cold after an initial charge, but there must be a slow leak somewhere.

Anyway... I found out that I'm getting laid off on Friday, so we've decided to put a little money into Earl to get him ready for the 1800 mile trip back home to PA. And as I get this work finished up, it has me thinking of some longer-term suspension goals on this truck.

Here's what's happening at the moment. Should finish up by the weekend, and I'll get some pics up.

1) Sway bars - 1 1/8" front, 7/8" rear

2) Bilsteins on all 4 corners. Front 24-192941, rear 24-002486. I couldn't find the rears for my truck listed, but capev86 listed these numbers in my initial thread. They should arrive today... hope they fit!!

3) U.S. Wheel Series 55 15x8 'Vette-style rallyes

4) Cooper Cobra radial G/T 255/70R15s

I'm thinking I should see a pretty dramatic improvement over the bone stock setup I was running. There was lots of lean in the corners, porpoising after road dips, etc. These upgrades should get me from Hobbs, NM to central PA comfortably and safely.

So my long term plans for Earl are to have a 3-season daily driver and fishing buggy. (This truck won't be exposed to Pennsylvania winter road salt!) Occasional long road trip on highways. He'll see some time on unimproved roads, but nothing that would require huge ground clearance or 4wd. There will almost always be some weight in the back - gear, dog, maybe a built-in but removable bunk for the longer fishing trips. And, if possible... he might eventually get the call to tow our '75 Airstream Argosy. But day-to-day handling and ride will trump towing in any suspension decision.

So I'm looking for advice and opinions as to how you would finish out the suspension mods. Earl might stay stock height, but a 2"-3" drop might be ok (which is why I'm not swapping springs yet - haven't decided on height!) but I want few/no clearance issues with the road/other suspension/chassis components. I would want to maintain the factory 2" rake. I'd also want to make changes that allow me to use the new components I'm installing this week if at all possible.

What I currently have in mind (in addition to the above list of things I'm doing now) is:

5) 2 1/2" drop spindles w/new stock 1/2 ton springs up front

6) 2" lowering blocks w/new stock 3/4 ton springs rear

7) adjustable panhard bar

I think this will get me a bit lower while keeping clearances, improve handling, improve hauling, and use the shocks, wheels and tires that I'm currently installing. I think any more drop than this will require shock relocators and the need to replace my brand new Bilsteins. Possible tire/wheel interference issues with the 255/70R15s. Suspension travel issues on unimproved roads. Etc.

So what say you? Is my plan reasonable for my desired outcome? Or are there options I'm not considering? Thanks in advance for any and all advice!

R
Posted via Mobile Device

[66 C10 383]

My main thought and concern is this. I know you'd want to reuse your new Bilstein shocks and run a 2" block. Can you run a 2" block with 15" tires and avoid scrub issues in case of a flat tire? I think I've read that you can run a 1.5" block in the rear without worry (unless you throw your tire completely off the rim ...)

Something to think about since your making a cross country trek ...

Everything else looks good to me.

[RyanAK]

That's something I'll definitely be looking at 66. Trying to get a good strategy for a practical mild drop with a minimum of issues. Hadn't considered issues in case of a flat...

None of the lowering will happen until we're back in PA. Just upgrading the shocks, wheels, tires, and adding sway bars for the trip.

Thanks for the input. I do appreciate it.

R

[66 C10 383]

Just passing that info along, I was also wanting a 2" block on mine and was pointed that out. I don't want to loose much suspension travel but I don't want issues if I have a flat cruising down the interstate either.

[RyanAK]

Definitely something to keep in mind. Thanks 66.

R

[Tx Firefighter]

You'll be fine with a 2 inch block. If there was no tire at all on the wheel, the u bolts might rub the ground, depending on how long they are below the lower plate. But, even the very flattest of tires wouldn't allow it to rub.
Posted via Mobile Device

[66 C10 383]

Originally Posted by Tx Firefighter

You'll be fine with a 2 inch block. If there was no tire at all on the wheel, the u bolts might rub the ground, depending on how long they are below the lower plate. But, even the very flattest of tires wouldn't allow it to rub.
Posted via Mobile Device

Good deal, I knew it'd be close with a 2" but wasn't quite sure. I'd rather err on safety side since mine will be a daily driver but I might just go 2" now. Mine is in no shape to tell at present ...

[RyanAK]

Good to know, TX. Any idea of other possible issues with the setup I'm planning on?

R

[Tx Firefighter]

Originally Posted by 66 C10 383

Good deal, I knew it'd be close with a 2" but wasn't quite sure. I'd rather err on safety side since mine will be a daily driver but I might just go 2" now. Mine is in no shape to tell at present ...

I am absolutely the most safety conscious guy you're gonna find. My first career was Airframe and Powerplant maintenance. I'm all about the safety. Like I said, just probably not clearly, is that a bare 15" rim bolted on with 2 inch blocks will be right at having the u-bolts rubbing on the ground when you set it down. Within a 1/4 of an inch either way. But, any flat tire, even completely blown out will add enough height that you'll be well clear of digging the u bolts into the asphalt.

Originally Posted by RyanAK

Good to know, TX. Any idea of other possible issues with the setup I'm planning on?

R

It's a good plan. Somewhere in the FAQ section is an article I wrote a long time ago about making lowering blocks. Back in the day when I was even more poor and couldn't afford to do anything, I built a lot of trucks with a simple 2 inch block in the back and one coil cut off the front spring. It was a nice way to drop a truck a little and give it "the look" without spending hardly any money. And it's bombproof, without any downsides.

[RyanAK]

I was thinking of making blocks... Haven't considered cutting a coil vs. spindles. Anyone have experience with ECE 2.5" drop spindles, 15x8 rallyes, 4.25" backspace, running 255/70R15s? Anything rub?

R
Posted via Mobile Device

[Tx Firefighter]

ECE spindles with 8 inch rally's will rub the wheel rim on the lower control arm. Much better option is to use 7 inch rally's on the front when using drop spindles.

Barring that, cut one coil from your front springs. That will give you between 2 and 3 inches of drop and not cause the rubbing issues like drop spindles will. That way is cheaper and allows you to use 8 inch wheels on the front.
Posted via Mobile Device

[RyanAK]

Thanks, mang!

Here's a photo of Earl with new 15x8 rallyes and 255/70R15 rubber. New Bilsteins. CPP front and rear sway bars will go on when they get here. (Couldn't find junk yard bars here in Hobbs, NM...) Whatcha think?



So if the 15x8s will rub, I'll definitely go with a spring/block setup. Will a 2" drop, either with a new spring or cutting a coil, require a different shock up front? I'd certainly rather swap out the new front Bilsteins for a drop shock than replace the new rallyes and rubber.

Man this place is great...

R

R

[Tx Firefighter]

Either a store bought 2 inch spring or a stock spring with a cut coil will be fine with stock length shocks. You're on a great path with that truck. Good choices on parts.
Posted via Mobile Device

[RyanAK]

Right on, Tx. I appreciate the vote of confidence.

R

[RyanAK]

So, I've run into a snag with the CPP rear sway bar. Or, to be exact, my mechanic has. I had to leave town for a couple weeks and had to pass off the install of the rear bar. Seems as though a body mount (which isn't there on a pickup!) interfers with the installation of the rear bar. Anyone else run into this, and is there a solution? (Front is perfect and makes a HUGE improvement in handling.)

Man this stuff is fun!

R
Posted via Mobile Device