We've barely even seen them on the street yet, and already Fabtech Motorsports has tackled the new '07 Chevys with a mission to make more than just the conventional IFS drop-down bracket kit. This is a brand-new model truck, and Fabtech decided to set the bar high right from the get-go with a full-option 4.0 Dirt Logic coilover offering to boost the new GMs 6 inches high to get 35-inch tires on. If the 4.0 Dirt Logic is a bit too excessive for what you're planning on, you can opt for a 2.5 Dirt Logic coilover, or even go with a simple factory coilover spacing bracket. Fabtech has covered the entire fullsize GM line, having rear kits for the leaf-sprung truck and the five-link coil-sprung Tahoe. By the time you read this, full production kits will already be on the shelves.
The kit consists of two Dirt Logic coilovers with about 6 inches of movement that nets you around 10 inches of front travel. Not a desert racer, but definitely better than stock. Fabtech uses the now conventional "knuckle lift" for the front, which keeps the upper A-arm in the stock locations and lowers the lower A-arm via two subframe drop brackets. The rear is lifted by two blocks using 2.25 Dirt Logic remote-reservoir shocks, and extends the bumpstops down to suit the lift height.
With the stock suspension...
With the stock suspension removed, the differential is the first thing to be placed on aluminum drop brackets, one on each framerail. The differential housing will need to be trimmed in three places, but no mounting points are taken away like many suspension kits called for on the '00-'06 trucks.
The subframe crossmembers,...
The subframe crossmembers, or drop brackets for the lower A-arms, bolt directly into the original frame holes for the lower A-arms. The front framehorns will need to be trimmed to allow the forward crossmember to slide in.
Instead of using one solid...
Instead of using one solid plate to join the two subframe crossmembers , Fabtech makes it a three-piece system so you can still drop the differential without removing the entire suspension system, should you need to change gears. Under the diff, a 1/4-inch skidplate joins both crossmembers, and between each A-arm bolt is a tubular brace.
We had little doubt about...
We had little doubt about a 2.5 Dirt Logic coilover slipping in place of the original equipment, but it was hard to imagine a 4.0 passing by the CV shaft and steering without ever rubbing. But here is Fabtech technician Danny Kempf slipping a big 4.0 Dirt Logic coilover into placement. It mounts to the factory coil bucket via an aluminum bracket that utilizes factory bolt holes.
New, beefier tie-rod ends...
New, beefier tie-rod ends are added to attach to the Fabtech knuckles. They'll withstand greater loads at more extreme angles than the factory tie-rod ends will.
The Fabtech knuckle simply...
The Fabtech knuckle simply bolts into place the same as the factory ones do. No hub or brake change is needed. The new knuckle is taller than the factory knuckle to allow the upper A-arm to sit in the stock location while dropping the lower A-arm.
The last bit of the kit to...
The last bit of the kit to fit is the impact struts that bolt onto the factory crossmember in the frame and join down at the rear subframe crossmember.
Here is the completed Fabtech...
Here is the completed Fabtech 4.0 Dirt Logic kit on the driver side of the truck. It will net you 10 inches of front travel, exceeding the factory specs and giving you a plush ride for your brand-new rig. The kit is simpler than previous Chevy IFS kits because Chevy now utilizes a coilover-type suspension from the factory, so you do not have to mess with torsion bars anymore.
The rear of Fabtech's truck...
The rear of Fabtech's truck uses a 4 1/2-inch block to lift the rear, while an extended bumpstop stops uptravel at the proper point. The 2.25 Dirt Logic remote-reservoir shocks bolt into the stock shock locations and handle damping duties in the rear.