The Rust Bucket of Baytown | ’72 GMC Sierra

This ’72 GMC Sierra here is rusty and covered in natural patina, and although it has been left in its original aged condition, it looks quite a bit better now than it did when Jesus Manchaca purchased it about 10 years ago. Of course, it stood quite a bit taller back then, but there was just something about it that had to be changed up.

“The truck was originally a three-quarter-ton camper special truck and, just like it sounds, had a huge camper on top of the bed,” Jesus says. “When I tore the truck down, I found the propane tank connections in the back under the frame, so this thing must’ve seen its fair share of camping trips in its lifetime.” 

Some trucks look good with camper shells on them, but if it’s not really going to be utilized, it’s probably better to just scrap the shell and embark on a brand-new start—that’s what Jesus did. 

“When I first spotted the truck, its owner told me it had already been sold to someone who had plans to part out the cab and front end and make a trailer out of the bed to haul scrap metal around,” Jesus says. “The poor truck was pretty much left to die out in the field where I found it, and it didn’t seem to have a bright future ahead of it. At that point, I was pretty bummed about the whole situation.” 

Even though Jesus was feeling the unique sting of despair that goes along with missing out on a cool truck project, he was about to receive a bit of good news that would change his outlook on everything. 

“A few months had passed since the GMC’s owner told me what was in store for his old truck, but for some reason or another, the guy who had bought it from him never went back to pick up the truck!” Jesus exclaimed. 

Sure, the truck wasn’t running, and it needed a whole lot of work to whip it back into shape, but for the bargain price of $1,000, Jesus was able to lock down a decent classic truck project. 

“I used to have a ’72 C10 when I was in high school,” Jesus says. “So, my plan for the Sierra was to build it the way I was not able to back then. I just had to figure out where to start on it.” 

Since Jesus already knew he wanted to go low with the truck, he ordered Porterbuilt’s front and rear drop member packages to add to the GMC’s original frame. But even though these modifications are pretty commonplace in today’s truck building community, this was probably a little more than nine years ago when there weren’t tons of documented installs to look on for assistance. 

“Porterbuilt was just getting into selling these drop member kits,” Jesus recalls. “Aside from the instructions that came in the boxes, there weren’t many reviews or insights to help online. I mostly relied on the help of fellow members of the www.67-72chevytrucks.com forum to make sure the install was moving in the right direction.” 

With the suspension taken care of, Jesus then began narrowing down the selection of what type of engine he’d use to replace the dead factory mill. The availability of LS engines has always been plentiful as of late, and the available amount of room underneath the hood of the GMC made the decision to purchase an ’08 LS3 easy to commit to. Jesus admits that just after he bought the engine, he had to start putting together the new puzzle he now had in front of him. 

“Once I had the LS3 picked out, I had to start figuring out answers to all the questions I had about how to wire up the Dakota Digital gauges to the ECM, which fuel pump to run, and how to tie in the air ride to have a read out on the gauge cluster,” Jesus says. “Of course, I anticipated and experienced the electrical gremlins that come with a freshly built truck, but all of that was expected to happen.” 

Jesus took full advantage of having a new engine to work with, as he outfitted it with an impressive lineup of performance add-ons. From starting with an engine that had died who knows how long ago, to having a fully decked-out powerplant complete with modifications designed to optimize horsepower and torque gains, the excitement level increased by the day. Along with the suspension and performance systems being upgraded, Jesus also spent a great deal of strategizing the changes to come within the interior space. Since he had decided to leave the exterior in as-is condition for the most part, he was able to focus on other aspects of the build to more quickly achieve his overall goal. 

Inside the cab, Jesus figured that some upholstery work, general cleanup and some tech upgrades would go a long way—and he was right. Linares Upholstery in Houston, Texas, was asked to join the project by recovering the factory bucket seats in material from PUI Interiors. Something as simple as recovering the seats made a huge impact on how the rest of the interior space could then be tied together. Original wood grain paneling was already in place throughout the cab from the door panels to the dash, but it was all left alone, as it gives the cab the perfect dose of original vintage styling that gives these old trucks their charm. A US Mags steering wheel and Dakota Digital instruments give interior a modern twist without being overly obvious. 

It has taken Jesus a solid nine years to get this far with his GMC project, and there are still more changes in store for the truck in the very near future. It has certainly been a labor of love over the last decade, but there are still things he’d like to get done. 

“Right now, we are working on a sub-woofer box for four JL Audio pancake woofers, kick panels to house component speakers and a center console where I can place the head unit,” Jesus says. “From there, I’ll also be working on front and rear tubs along with the doghouse. The hood and cowl panels will also be swapped out for pieces that have a little more natural green color in them. For the most part, I just want this truck to look more complete and finished even though it will still look like a low-riding rust bucket.” 

Until all those boxes are checked off, Jesus plans to drive his GMC as much as possible, especially since his other Chevy truck projects are currently eating up much more time and money than expected. Yep, he has more of these trucks lying around just waiting for their turn for attention.   

Truck Specs
Jesus Menchaca
1972 GMC C15
Baytown, Texas 

CHASSIS 

• Shop: Drops R Us & Bernal Auto Designs, Pasadena, Texas 
• Factory ’72 GMC short bed frame 
• Porterbuilt front and rear dropmembers installed 
• KYB front and rear shocks 
• Rack and pinion steering 
• Factory front disc kit from CPP, rear six-lug conversion kit from CaptFab
• Corvette master cylinder 
• Hydroboost assisted from hydroboost.com 
• Metalworx.com custom fuel cell 

WHEELS and TIRES

• 22 and 22-inch US Mags Kompressor wheels 
• 255/30/22 and 275/30/24 Win-Run tires 

ENGINE 

• 2008 Chevrolet 376 LS3
• Porterbuilt LS engine mounts used for the Dropmember 
• PSI LS swap harness 
• Dirty Dingo A/C bracket 
• Kwik Performance accessories bracket
• LS1 water pump
• Texas Speed camshaft 
• Ported and polished titanium valves 
• Edelbrock Vic Jr. intake manifold and fuel rails 
• Magnafuel fuel injection
• Hedman “Hustler” headers 
• Black Widow Widowmaker mufflers 
• Nick Williams 102mm throttle body 

TRANSMISSION 

• Shop: Lou’s Trans and Auto, Baytown, TX & CT Driveshaft, Houston, TX
• 2008 4L60E transmission 
• Porterbuilt cross member  
• Circle D billet single disc converter
• Tru-Cool trans cool

BODY 

• The original patina on dark olive and white paint 
• Luverne brush guard 
• Original GM bumpers 

INTERIOR 

• Shop: Linares Upholstery, Houston, TX
• Original bucket seats rewrapped in PUI Interiors green houndstooth material
• Dakota Digital VHX instruments 
• US Mags Kompressor steering wheel 

CAPTIONS: 

Brush Guard Close Up Pic: A brush guard was added to the Sierra’s front end to give it that old school utilitarian/farm truck feel. 

Interior Pic: Linares Upholstery covered the original bucket seats with green hounds tooth material from PUI Interiors. 

Steering wheel & gauges pic: A US Mags Kompressor steering wheel and Dakota Digital gauges give the Sierra an updated appeal to the upgraded cab. 

Wheel pic: Choosing a set of wheels for an old, rusty GM pickup that don’t use hubcaps can be a tough call. The selected US Mags Kompressor wheels have an aggressive styling that surprisingly works well with the truck’s naturally weathered façade.