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1971 Chevy Suburban - Project SuperBurb, Part 1

Stronger Axles and Better Brakes

By Craig Perronne
photographer: Craig Perronne

 1971 Chevrolet Suburban Left Front View

We have always been fans of Chevy Suburbans. Built the right way, a Sub can tow a house and still go wherever there’s room on the trail for it to fit. It can do all that while hauling you and all of your friends, and all your gear, along for the ride. When you get tired, you can just lay down for a nap in its massive interior.

It was with those positive traits in mind that we started looking around for a ’73-’91 Suburban. We wanted to stick to those years because they are still leaf-sprung, with solid axles front and rear. Plus, with so many Burbs of that era out there, parts are plentiful. Then our plans changed: One day we happened across a ’71 Suburban. It was for sale. We have always been suckers for the funky styling of the ’67-’72 three-door Burbs and couldn’t resist taking a look. This beast was beat and battered and would be plenty of work to make into the rig we wanted, but the potential was obvious. There was no way we could pass it up.

We bought it, and thus began a massive project to transform our sub-par Burb into SuperBurb. From towing to trail running to exploring Baja to driving to work, we want the Burb to be able to handle a wide variety of tasks with ease. For our first part of the project we focus on stronger axles and better brakes. What follows is a chronicle of what we did and how we did it.


 1971 Chevrolet Suburban Axle View
A Corporate 12-bolt axle held up the back of our Burb. We knew that this piece just wouldn't cut it, as these axles have never had a great reputation for strength, and their semi-floating design is not the ticket for towing. Maybe it's just us, but there's something about spitting off a wheel, at speed, with an 8,000-pound trailer behind us, that isn't terribly appealing.
 1971 Chevrolet Suburban Rear Axle
Our weapon of choice for the rear axle is a full-floating and plenty stout Corporate 14-bolt built by Off Road Unlimited in Burbank, California. For our application ORU chose a housing out of a van. These are 3 inches wider than standard housings. This way if we ever decide to replace the front Dana 44 with a Dana 60, the track widths will match.
 1971 Chevrolet Suburban Differential
To help in the traction department we contacted Reider Racing, which sent us a Detroit NoSpin. It operates exactly like a Detroit Locker but is a little different because it goes inside the carrier instead of replacing it. The NoSpin is really the only locker available for the 14-bolt but that's fine with us, as it is strong and simple.
 1971 Chevrolet Suburban Differential
Reider Racing also sent us a 4.88 ring-and-pinion set from Precision Gear for the 14-bolt. While 4.88:1 might sound a bit low, this ratio was chosen because we have plans for an overdrive in the future.
 1971 Chevrolet Suburban Brake Caliper Mount And Spacer
To help the big Burb stop better, we had the techs at ORU add the company's disc brake kit for 14-bolts. The caliper mounts and spacers went on first.
 1971 Chevrolet Suburban Brake Disk
The ORU brake kit also includes slotted rotors. These were next to slide into place. If you have a later-model Chevy ('92 and up), the rotors and hub come completely assembled. For early Chevys you simply reuse your existing hubs.
 1971 Chevrolet Suburban Brake Assembly
Calipers are part of the package. We opted for the ones with built-in emergency brakes. Steel braided lines and pre-bent hard lines, along with the tabs needed to mount the emergency brake cables, are also included in the kit.
 1971 Chevrolet Suburban Brake Proportioning Valve
Another key part of the kit is the proportioning valve, specifically made for discs front and rear. It helps provide a firm pedal and better stopping power.
 1971 Chevrolet Suburban Welding Suspension Mounts
With the 14-bolt assembled, the next step was to pop it into the back of the Burb. The spring pads had to be moved because of the extra width of the van housing. Once the pinion angle was correct they were welded into place. New lower shock mounts also were welded up at this time.
 1971 Chevrolet Suburban Differential Cover
For extra fluid capacity and cooler running, we bolted on ORU's diff cover. We opted for the black one but they are also available polished, if that is more your style.
 1971 Chevrolet Suburban Axle View
Behold, the finished product in all its glory. With a 14-bolt stuffed with 4.88 gears, a NoSpin, and disc brakes, the rear of our Burb is ready for anything we can throw at it.
 1971 Chevrolet Suburban Drive Shaft
Our original driveshaft wouldn't work because a 14-bolt uses 1350 U-joints and our 1/2-ton shaft came equipped with wimpy 1310s. The 14-bolt's pinion also is 2 inches farther forward than it is on the 12-bolt. We didn't want to build new driveshafts until our new suspension and drivetrain, all of which we'll tell you about in future issues, were in. Lucky for us, one of the guys at ORU had a driveshaft out of a '72 3/4-ton Suburban lying around in his scrap heap that we could temporarily use. All we had to do was change out the 1310 U-joint yoke on the transfer case for a 1350.
 1971 Chevrolet Suburban Front Differential
Moving to the front, we decided to keep the Dana 44 in place to save some bucks, as Dana 60s tend to be a bit spendy. Our first step was to head down to Drivetrain Direct, where an Ox Locker was installed for maximum traction.
 1971 Chevrolet Suburban Differential Locker
We took our Ox Locker apart to get a look at it and were impressed by its strong construction and quality. While Drivetrain Direct was putting in the Ox Locker, the technicians there also installed a set of 4.88 gears from Superior Axle & Gear.
 1971 Chevrolet Suburban Differential Locker Actuator Arm
The cool thing about the Ox Locker is that it acts as an open differential until it is engaged via a cable shifter. Then it locks completely. The actuator arm is built into the cover, which is made out of billet and looks like it could survive a nuclear blast.
 1971 Chevrolet Suburban Differential Locker Shifter
Even the shifter for the Ox is trick and stout. Machined from billet, it actuates the locker with the attached cable. We decided to wait to finish the interior of the Burb before we mounted it inside.
 1971 Chevrolet Suburban Front Hub
After installing the Ox Locker, we headed back to ORU to convert the front hubs to eight-lug to match the rear 14-bolt. First to go on were spindles and backing plates from a '73-'77 Chevy 3/4-ton Dana 44.
 1971 Chevrolet Suburban Brake Rotor
Rotors from a '73-'77 Chevy 3/4-ton Dana 44 also are needed for the eight-lug conversion. While you can find these in a boneyard, we decided to run these slotted ones from ORU. A nice feature of the 3/4-ton rotors is that they are almost an inch larger in diameter, which means that they provide more surface area, which means more stopping power.

 1971 Chevrolet Suburban Brake Caliper

The same caliper that came on your 1/2-ton Dana 44 can actually be used when you convert to eight lugs, but we decided to upgrade to the 3/4-ton calipers from a '73-'77 Chevy Dana 44 as they use a slightly bigger piston. Another part that can be reused from the 1/2-ton Dana 44 is the locking hub. With all those parts in place our Dana 44 was now eight-lugged, stuffed with a stout Ox Locker along with 4.88 gears, and ready for action.

Project SuperBurb- Part 2
Project SuperBurb- Part 3
Project SuperBurb- Part 4
Project SuperBurb- Part 5
Project SuperBurb- Part 6


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