CARBURETOR AND AIR TRANSFER PIPE GROUP 6L2529 - Caterpillar

Shallow Sump Oil Pans
These pans are identified by two stiffening ribs (one on each side) stamped into the bottom surface of the pan in the transition area between the shallow end and the deep end. In addition, the drain plug on the bottom is located in a rectangular stamped boss. See Illustration 1 for identification.
Illustration 1. Shallow sump oil pans.All NA engines with this pan (except marine engines) have a total capacity of 11.5 L (12.0 U.S. qt) (including the filters). Engines with this pan should have a difference of 2 L (2 U.S. qt) between "Add" and "Full" on the oil level gauge.
All marine engines use a modified version of this pan, but because of remote mounted filters and lines, they require slightly more oil than other NA engines which use the shallow sump oil pan. Naturally aspirated marine engines have a total capacity of 12 L (13 U.S. qt) (including filters). The oil level gauges and guide tubes are connected directly to the pan, rather than the cylinder block. See Illustration 2 for identification of the marine oil pan.
Illustration 2. Marine oil pans (modified shallow sump).Deep Sump Oil Pans
These pans are noticeably deeper than the shallow sump pans. However, these pans do NOT have either the stamped stiffening ribs, or the stamped oil drain boss that are found on the shallow sump pans. The deep sump pans are smooth in both of these locations. Naturally aspirated engines with this deep pan now have a total capacity of 15 L (16 U.S. qt) (including filters), and now have a difference of 2 L (2 U.S. qt) between the "Add" and "Full" marks on the oil level gauge. See Illustration 3 for identification of the deep sump oil pan.
Illustration 3. Deep sump oil pans.Center Sump Oil Pans
These pans have the deep part of the oil pan in the center instead of at one end. NA engines with this pan have a total capacity of 13 L (14 U.S. qt), and have a difference of 2 L (2 U.S. qt) between the "Add" and "Full" marks on the oil level gauge. This pan is usually used on some naturally aspirated industrial and earthmoving equipment engines. The oil level gauge and guide tube are usually connected directly to the pan, rather than the cylinder block. See Illustration 4 for identification of the center sump oil pan.
Illustration 4. Center sump oil pans.