Are 8-pin and 6-pin drive-by-wire throttle bodies interchangeable?

Here is what the documentation says. Each point links to its source; details depend on your exact computer, harness and transmission.

• 2003-2013: Per the Terminator X manual, LS DBW throttle bodies came with two connector styles: an eight-pin connector on early trucks and a six-pin connector on passenger cars and 2007+ trucks. (Holley)
• 0411; LS1, LS6; 1997-2004: The C5 Corvette DBW throttle body is a 78 mm, three-bolt unit with a six-pin TPS connector on the passenger side and a barrel-shaped two-pin drive motor on the driver side; it works only with 411 PCMs (red/blue connectors) and the early-style TAC module, and is unique to C5s. (LSX Magazine (Power Automedia))
• 0411; LM7, LQ4, LQ9; 2001-2002: The 2001-2002 truck/SUV DBW throttle body looks like a mirrored C5 unit (TPS on the driver side, drive motor on the passenger side) with the same six-pin and two-pin connectors, but the wiring differs and it is not interchangeable with the C5 body. (LSX Magazine (Power Automedia))
• 242; LM7, LQ4, LQ9, LM4, L59; 2003-2007: The 2003-2007 truck/SUV DBW throttle body keeps the 78 mm blade and three-bolt pattern but uses a single eight-pin connector behind a black plastic side cover; it works only with 242 PCMs (green/blue connectors) and the later plastic/metal TAC module. (LSX Magazine (Power Automedia))
• E38, E67; LS3; 2007-2013: The later gold-blade Gen IV throttle body looks exactly like the silver-blade LS2 body but is not interchangeable with it. (LSX Magazine (Power Automedia))
• E38, E67, E92; 2007+: The Gen 4 LS and Gen 5 LT throttle body connectors are both six-pin but have a different shape, and LT bodies use a digital signal while Gen 4 units use analog; no adapter allows interchanging them. (LSX Magazine (Power Automedia))
• 0411, 242, E38, E67, E92; 1997+: Eight-pin and six-pin DBW throttle bodies are not freely interchangeable: the eight-pin 78mm three-bolt 2003-2007 truck body pairs only with the 242 PCM and late TAC, while six-pin bodies span C5/early-truck (411/early TAC), 2007+ four-bolt Gen IV (E38/E67), and LT (E92, digital) systems that are mutually incompatible. (LSX Magazine (Power Automedia))
• 2003-2013: Late Model Resto documents that GM LS DBW throttle bodies came in eight-pin and six-pin connector styles. (Late Model Resto)

Confirm against the instructions for your exact parts before wiring. More: Throttle (drive-by-wire) in our tuning guide.