'71 Burb "Earl" suspension

[RyanAK]

Hey, gang. Remember Earl?





Well we've been having fun driving him around on short trips here in eastern New Mexico. Even got the 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 having 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 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 using 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.

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

[tlcrz1972]

If your going to be hauling loads in the back and possible trailers. Get an air bag assist on the rear suspension. When it's not loaded you get the comfort of the stock typeish springs and shocks. but when you load it down. Shoot a little air to the bags and it'll handle everything (within reason) that you can load into it.

I've done this on my 72 pu and know when she gets a trailer behind her she will ride just right and not be a noodle in the rear.

If you want pics I can get some.

[RyanAK]

Hey tlcrz1972 - thanks, I'd appreciate some photos. I have NO experience with air. I'd also be interested in what hitch receiver you're running. I have an Andersen in the stock receiver of my '04 Z71 Suburban, but towing with '71 will be a new experience.

Thanks,
R

[tlcrz1972]

Sure I'll get you some pictures of the air bags.

I'm running a class 3 receiver hitch, and won't do anything less.

As far as a hitch, I don't know if anyone offers a receiver hitch for 67-73 burbs.
If not your next option is to find a receiver hitch that works on a 1973 and up suburban. (Pickup hitches won't work.) The kicker is that it will have to have the plates cut off and moved inboard to match your frame rail width. And of course re-welded into position.

I did this on a friends 72 Jimmy and it worked out perfectly. Next time I see him I'll get some pictures of it.

[tlcrz1972]

Here's a few pictures of the air bags I put on it.

IDK on what brand they are. It's been many years ago that I did it.

I do remember that My dad had them on his 1981 3+3 3/4 ton. He took them off when he sold it and I bought them.

I installed these without any cutting or removing of the snubber brackets off the frame. and the perches that instal on the rear end fit just perfectly around the trailing arm u-bolts and any other pieces.

[Average Joe]

Sounds like a great plan for earl. Im planning a similar drop this winter on my 67. I definitely need some bags on the back of mine or stiffer springs tired of the bouncy ride when towing my TT. I just got a smokin deal on a Hensley Arrow so the combo should be the cats pajamas. I think you will like the look of the 255/70's. BTW have you thought about cutting a coil off your existing springs instead of drop spindles?

[RyanAK]

Thanks for the photos of the helper bags, tlcrz1972. That sure helps.

Joe - I'd be interested to know what combination of springs, shocks, spindles, blocks, bags you're thinking of. Ditto tires. I think the Cooper radials will be great street tires, but question their weight rating for towing.

I've also been looking at the Hensley/ProPride... I have some geometry issues with the Argosy/'04 Suburban/Andersen hitch that causes sway issues. There was an incident driving across Texas where I thought I was going to buy it. Never been that frightened, and I've been drug overboard of a commercial fishing boat in Alaska.

R

[RyanAK]

Guess I should add that I THINK I'm going to get the sway bars on... having a terrible experience with a certain supplier. Ya'd think they'd be up on service when the economy is making wallets tight... I'll take my money elsewhere.

R

[Average Joe]

Hey Ryan my combo so far is pretty basic and lo buck. 7/8 front sway bar with 20 yo bushings, new stock height springs front, original rear springs with half leaf factory overload, 15x8 6 lug rallys with 255/70/15 indy 500 firestones. im currently running a ez lift load leveling hitch with a single friction damper and class 3 receiver unknown brand modified to fit from an 86 burb. I also have cheap gas matic monroe shocks at all 4 corners. I think I definitely have room 4 improvement.
My winter plans call for a 2 inch block in the rear along with some air lift helper bags and possibly HD rear springs. Considering a rear sway bar as well. in the front I am going to cut a coil and replace the sway bar bushings.
I'm still debating weather to put in my 3.07 gear rear end or stick with the 3.73's. The concern i have with the 3.07's: I know they will improve my mileage when empty but may hurt mpg while towing in the mountains. The 454 makes gobs of torque but is also very thirsty.

I like your list of planned mods. Since you mentioned your concern about the tires I will give you my thoughts. I love my 15 inch rallys but I cannot find any D rated let alone E rated tires in 15 inch. I think if I were to spend the money on new rims I would consider a 16 inch or larger rim that I could find a load rated tire for. The only concern being when towing my 6k lb TT.

[RyanAK]

Hey, Joe. Sounds like we have similar plans for our 'burbs. Your thoughts on rear suspension mirror my own for sure. I have a 3.73 rear, and I'll keep an eye on milage on the 1800 mile drive to PA. I for sure couldn't go to 3.07 with my 350 and plan to tow very much. 454 certainly changes things though! What tranny are you running? A swap to an OD transmission is on my 'some day' list.

Plan for tires is to run the radials on rallyes and have a set of 'tow' wheels/rubbers on 16" truck rallyes, wagon wheels, etc. I honestly won't tow very often, so would like to keep the 15"s and radials for daily use, then swap out to a higher rated set to drag the 22' Argosy... though "Supertramp" only weighs 3800 lbs dry. Maybe I'm overthinking this...

This stuff is fun, ain't it?

R

[Average Joe]

Hey Ryan, Im running a TH400 stock except for a shift kit. Ive considered a 4l80 with stand alone controller or a used gear vendors to go behind the th400 but its hard to justify spending that much. I had a chance to buy a 86 dually with a running 454, th400, and gear vendor unit for $1800 but was unable to come up with the money at the time. (dang mortgage and mini van payment ) I could have pirated the overdrive and resold the truck with a longer driveline and gotten a stout O.D. for 600 bucks.

[RyanAK]

Wow, Brian (sorry, i knew it wasn't Joe!) The gear vendors OD would have been a steal. I know how it goes though... Right time, wrong checking account balance. Heh.

Is the TH400 a 4 gear tranny? What RPMs are you running at normal highway speeds?

R
Posted via Mobile Device

[Average Joe]

TH400 is a 3 speed auto with 2.48 1st gear, something else for 2nd idk, and 1 to 1 in drive. Im around 2700 at 60mph.

[RyanAK]

Thanks, Brian.

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. Whatcha think?



I've heard that 15x8s can rub the LCA with drop spindles, so I might change to 2" front springs and 2" rear blocks to avoid this. Will the new front Bilsteins need to be swapped if I go with a 2" front coil drop?

R

[Average Joe]

Looks great Ryan! Ive never ran dropped spindles so I dont know. You might want to ask this question in the suspension or main forum.

[RyanAK]

Responses in the Suspension forum say 15x8s will rub on the lower control arm with a 2.5" spindle, but a 2" spring (or one coil cut) will be good to go and can use the Bilsteins as-is. 2" rear blocks seem like the way to go, except that CPPs website says something along the lines of a 2" block isn't recommended with a 15" wheel... hmmm...

Rust control and some performance upgrades will be tops on the list for when we get back to PA, so I have some time to figure out the rest of the suspension build. But I think front springs, rear blocks, adjustable panhard bar, and new poly trailing arm bushings will sit just right.

Thanks for the encouragement!

R

[LockDoc]

-
Burb is looking good!

LockDoc

[RyanAK]

Thanks, Leon!

Brian, I've been thinking about your rear end swap to 3.07 ratio, since I'm considering the same. I think your 454 has the torque to overcome the gearing off the line and will live an easier life with lower RPMs at highway speeds. Not as good as OD, and prob won't see much in the way of mpg... But I think it would be worth the effort if not swapping transmissions. At 70mph with 255/70R15s and 3.73 gears, my 350 will be wound up to 3020 RPMs. Go to 3.07, and I'm down to 2486 RPMs.

I've also 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 so 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

[Average Joe]

Glad to hear you received your sway bars Ryan. You might want to pm Capev86 about the rear sway bar. IIRC he used aftermarket sway bars on his or at least was thinking about it.
I still havent got my 3.07's installed. Ive been busy working on the TT. I figured for the cost ($150) for the complete rearend with brand new brakes and good drums I couldnt go wrong. Heck if I can pull down 12mpg empty hwy I'll be back to where I was with the worn out 283/4 speed/3.73 combo.

[Average Joe]

Updates?

[AzDon]

FWIW.....If you use spindles and lowering blocks, the travel on your shocks will not be shortened as they will if you use shorter springs.....I mounted stabilizer bars from an 87 IROC camaro and my burb turns like a go-cart! I havent really done any towing (I've got a 94 dually for that!) but would do some kind of bagging if I was going to. Air-Lift claims they can set me up with in-the-coil bags for front or rear coils if called with measurements. My burb has 2.5 spindles on the front with one coil removed for about a five inch drop and, honestly, it's a little too low for normal use. I have stock truck ralleyes off an 88 van on the front (without ANY clearance issues) and similar 4x4 ralleyes (wide and offset) on the rear with 2" blocks..... I've got a CPP adjustable Panhard Bar and I'm unhappy with it..... First, It has cheezy plastic bushings that don't last and replacements are costly when they should be free because of the piss-poor design.... Also, it turns out that the adjusted bar on the 2" lowered rear is EXACTLY the same length as stock....so wasnt necessary!