A Step-by-Step Guide to Adding Air Suspension on ’88-’98 GMT400 Chevy Trucks
In the first-ever OBS Builder’s Guide, (March ’20) we focused our attention on swapping out the factory installed 4.3-liter V-6 engine for a Blueprint Engines 383c.i. stroker motor. Additionally, we added an American Powertrain transmission, along with a full Ridetech coilover suspension system and 22-inch American Racing wheels. It was an impressive truck that was built right from Day 1 and driven hard like it was intended.
So now, we’re going to turn our attention to the OBS Builder’s Guide V2 donor truck, a 1997 GMC Sierra dubbed Project Artemis that’s sporting a 5.7-liter V-8 with the third door option and only 125K original miles. She’s a completely clean—and 100% stock—extended cab OBS GMC that’s just begging for a new life, and we have a goal to give her one.
For this build, we will focus on adjustable suspension and bolt-on options for bagging your ’88-’98 OBS truck. Using a very well-engineered Ridetech air-ride suspension along with Ridetech’s patented air management system, we will simply cut off the old suspension mounts and bolt this complete system to the factory frame rails. No welding, no fabricating and, best of all, no cutting the bed!
With a new suspension in place, the factory wheels and tires will kill the new look of the truck. We didn’t want to make this truck unrelatable to the average consumer, so we went with an extremely affordable wheel from U.S Mags called the Bullet, and wow, they are nice! Toyo Proxes STIII tires will surround the rims and a new set of EBC Brakes will tuck nicely behind them. Once the suspension is complete, we will show you guys a super cool new product from BedWood and Parts called a retroliner. Yes, you can now put a wood bed floor in your OBC truck, too!
For this new suspension special, we will be working with the amazing crew SaltWorks Fab in Myakka City, Florida. They are experts at metal fabrication and suspension setups, and the work they put out is second to none. Producing Concours d’Elegance builds to compete at Pebble Beach is the daily grind for this team, so dropping the welders and bagging our OBS will be a cake walk for Thom Ophof and company.
Before we jump into the tech, we wanted to lay out the plan, show you the parts and ideally inspire you to follow along on your own OBS.
This Ridetech air suspension system for two-wheel drive, ’88-’98 Chevy/GMC C1500 trucks includes front tubular upper and lower control arms, drop spindles, bolt-on wishbone rear suspension, front HQ shocks, rear HQ Shockwave airbags, as well as a front sway bar. The benefit of buying a complete suspension system is that it takes all of the guesswork out when purchasing a new suspension.
Ride height that is approximately 4 inches lower than stock in the front and 6 inches in the rear. Fully deflated will net an additional 3-inch drop.
Front CoolRide setup includes HQ Series shocks and bolt-on upper shocks mounts to allow more ground clearance and maximum suspension travel.
The upper StrongArms control arms feature corrected ball joint angles for the lowered ride height, and the length has been altered to create more camber adjustment.
The lower StrongArms feature a double sheer lower shock mount for increased strength and have a lowered shock mount to increase suspension travel as well as more camber adjustment.
The front MuscleBar sway bar reduces body roll and includes the Delrin liners to minimize suspension bind.
Ridetech’s drop spindles greatly improve suspension geometry and bump steer.
The rear bolt on three-link does not require any welding or major modifications to the bed floor.
THE FRONT INSTALL
Stage one for this multi-stage resto-mod is to replace the front and rear suspension. We don’t want to be cutting and grinding the frame with the custom wrap we have planned, and we definitely don’t want any greasy mechanics getting in and out of our nice new interior. So, we called up Ridetech, told the crew our goals, and they helped us order a complete, turn-key air-ride system designed to fit ’88-’98 Chevy and GMC C1500 trucks.
Once the complete kit arrived, we packed everything up and headed out to SaltWorks Fab in Myakka, Florida, for the install. Chris Hagerty and Telly Violleto were excited to break away from their high-end fab work for a couple days to bag our OBS, and we were there pestering them throughout the whole process.
THE REAR INSTALL
Next up, we tackle the rear of our 1998 GMC Sierra 1500 SLE with a C-notch install and a lot of sweet looking, well-engineered suspension parts. The final piece to the new suspension puzzle is picking a wheel and tire package.
For project Artemis, we wanted a setup that would allow us to have a super low stance without cutting anything and a decent ride on 40-series tires. If you have any experience with air suspension, county roads and 35-series tires, you will more than likely understand our desires for this driver. The wheels are staggered fit, 20-inch aluminum wheels from US Mags with a width of 8 inches up front, and 9.5 inches in the back. Having a wider wheel in the back not only looks cool, but it also stretches the 40-series tire just a bit to give up some extra clearance out back when cruising low and slow.
Now let’s check out the steps to installing the rear of this extremely well engineered air suspension system for GMT400 trucks.
For project Artemis, we decided to venture into the world of wraps. The body isn’t great, we don’t have time for a color change, and a full custom paint job was never in the budget. So, some digital graphics printed on vehicle wrap material will cover up the factory coating.