Removing GM Small Block Engine - Gen III V-8 R&R Basics

This is part one of two stories detailing the process of the removal and reinstallation (R&R) of the Gen III V-8 from a GM fullsize truck or SUV (which would include Chevy, GMC, Hummer, and Cadillac vehicles). The Gen III V-8, commonly referred to as an LS1 (see sidebar "LS1 or Gen III?" for more on this), has been powering GM trucks and SUVs since 1999. So this information will help you when removing an engine on any Gen III V-8-powered GM truck built from 1999 to the present.

As simple as it may seem to pull a V-8 engine from a full-frame vehicle, just getting the Gen III V-8's wiring and plumbing unhooked can be frustrating if you haven't done it before. As most of the difficulty is in the details, these stories will show you what pieces to work with and how to finagle them off the vehicle to maximize success. To simplify the explanation, this story uses more photos than text. In fact, this story is an excerpt from the upcoming book, How to Build Performance Chevy LS1/LS6 Engines, by Will Handzel (see sidebar). The book has a chapter with more than 150 photos, showing how to remove the Gen III V-8 from multiple types of GM vehicles. If you want to see practically every step to R&R'ing a Gen III V-8 from a fullsize truck/SUV, a Vette, and the Camaro or Firebird, get the book.

LS1 Or Gen III?
The first the public ever saw of the General Motors Gen III V-8 was in the completely redesigned '97 Chevrolet Corvette. That vehicle, and the engine that came in it, made such an indelible mark the engine architecture has become commonly known by the regular production order code (RPO) that was assigned for that vehicle: LS1.

Inside the production vehicle world (that would be mainly GM and its suppliers), the engine architecture is actually called Gen III V-8 because it powers multiple vehicles in multiple power levels and is denoted by multiple RPO codes. For more on this, see the sidebar "Common Gen III V-8 Engine RPO Packages and Power Output."

Many enthusiasts still call the engine in their Escalade an LS1, even though the RPO for that engine is LQ9. Is it wrong? That's for someone else to decide. To avoid confusion in this story, we'll call the engine a Gen III V-8 -you call it what you want.

Service Bay Cred
The tips and tricks listed here are a little from the GM manuals, but mostly from the technicians doing this work every day. These techs have discovered ways to simplify the task of pulling a Gen III V-8 engine while minimizing the amount of work and the possibility of damage to the vehicle components at the same time.

Just so you know, the R&R of a Gen III V-8 from the Camaro/Firebird (what GM calls F-car internally) and Corvette (Y-car) is more involved than the R&R on the fullsize trucks (called the 800-series internally within GM). This is because the engine must come out of the vehicle from underneath on the F- and Y-cars, while the truck engines come out the traditional method - over the radiator core support. For all these vehicles, including the trucks, being able to put the vehicle on a lift will make the job of R&R'ing the engine easier.