The following is a list of GM bellhousing patterns. Though General Motors has manufactured many different engines, it has kept variance in the bell housing patterns to a relative minimum. Chevrolet V8 pattern This was so named because it began with Chevrolet's V8 engines. Chevrolet big-block V8s Chevrolet small-block V8s GM Vortec 4300 90° V6 GM Iron Duke RWD inline 4 (early RWD Variants, later versions may use a FWD pattern, and have two possible starter locations) Jeep with GM Iron Duke inline 4 2.5L/151 in³ (1980-1983). These use a Chrysler custom Torqueflite 904 automatic transmission with an integral Chevrolet bellhousing. Do not confuse with later AMC 2.5 L engine that uses GM small corporate pattern (see below). Chevrolet Turbo-Thrift engine (post-1962) Chevrolet 153 Inline 4 (Chevy II, pre-Iron-Duke - includes the Vortec 3000/181 industrial/marine crate motor) Detroit Diesel V8 6.2L and 6.5L Duramax V8 Generation III V8s with modifications. These modifications include an additional bolt hole at the top of the pattern, and attachment points for cast oil pans to lower bellhousing extensions, to reduce NVH. GM metric pattern Also called the GM small corporate pattern and the S10 pattern This pattern has a distinctive odd-sided hexagonal shape. Rear wheel drive applications have the starter mounted on the right side of the block (when viewed from the flywheel) and on the opposite side of the block compared to front wheel drive installations. The 2.2l S10/Sonoma had the starter located in the same position as front wheel drive cars. A rear wheel drive bellhousing is displayed at right, and the integrated front wheel drive bellhousing is displayed at the lower right (in this case, as a part of the GM 6T70 Transmission). GM 60-Degree 2.8/3.1/3.4/3.5/3.9 L V6 (also used by AMC) Buick 3300/3800 V6 Cadillac HT4100/4.5/4.9 L V8 Isuzu all 3.2 and 3.5L DOHC V6 AMC/Chrysler 2.5L I4 found in Jeep Cherokee, Comanche, Wagoneer, CJ and Wrangler and Dodge Dakota GM Iron Duke/Tech-4 2.5L I4 GM "122" 1.8/2.0/2.2 L I4 GM 5.3L LS4 V8 GM High Value engine Northstar pattern Nearly identical to the GM small corporate/metric pattern, except that the starter is located between the cylinder banks, and the lower right bolt hole is moved outward by roughly one inch. Being nearly identical, it too has the distinctive odd-sided hexagonal shape. These engines can be fitted in rear wheel drive vehicles with the right bellhousing and are used in