Model Identification
Truck models, listed in tables, are identified using manufacturer's letter and number designations. The letters identify vehicle model series (i.e., "C" is conventional chassis, including Pickup, Blazer and Suburban). The number reference identifies the vehicles load capacity. Refer to following charts for actual letter and number designations.
VEHICLE SERIES IDENTIFICATION
| Vehicle Series | I.D. Letter |
|---|---|
| Conventional Chassis (2WD) | C |
| Conventional Chassis (4WD) | K |
| Conventional Van Chassis | G |
| Forward Control/Step Van Chassis | P |
VEHICLE LOAD CAPACITY
| Chevrolet Number | GMC Number | Ton Capacity |
|---|---|---|
| 10 | 1500 | 1/2 |
| 20 | 2500 | 3/4 |
| 30 | 3500 | 1 |
GENERAL MOTORS VACUUM DIAGRAM REFERENCE CHART
| Engine & Model | Application | Transmission | Illustration | |
|---|---|---|---|---|
| 4.3L V6 | ||||
| G10 | Fed. | All | Figure | |
| G10 | High Alt. | All | Figure | |
| C10 & K10 | Fed. | All | Figure | |
| C10 & K10 | High Alt. | All | Figure | |
| G10/20/30 | Fed. | All | Figure | |
| G10/20/30 | High Alt. | All | Figure | |
| C10/20 & K10 | Fed | All | Figure | |
| C10/20 & K10 | High Alt. | All | Figure | |
| G10/20 | Calif. | All | Figure | |
| C10/20 & K10 | Calif. | All | Figure | |
| 4.8L 6-Cylinder Heavy Duty | ||||
| C20/30, K20/30 & P20/30 | Fed. | All | Figure | |
| 5.0L V8 | ||||
| C10 | Fed. | Auto. | Figure | |
| C10 | High Alt. | Auto. | Figure | |
| C10/20 & K10 | Fed. | All | Figure | |
| C10/20 & K10 | High Alt. | All | Figure | |
| G10/20 | Fed. | All | Figure | |
| G10/20 | High Alt. | All | Figure | |
| C10/20 & K10 | Calif. | All | Figure | |
| G10/20 | Calif. | All | Figure | |
| 5.7L V8 | ||||
| C10/20 & K10/20 | Fed. | All | Figure | |
| C10/20/30 & K10/20 | High Alt. | All | Figure | |
| G10/20/30 | Fed. | All | Figure | |
| G10/20/30 | High Alt. | All | Figure | |
| C10/20 & K10/20 | Calif. | Auto. | Figure | |
| G20/30 | Calif. | Auto. | Figure | |
| C20 & K20 | Fed. | All | Figure | |
| C20 & K20 | High Alt. | All | Figure | |
| G30 | Fed. | Auto | Figure | |
| G30 | High Alt. | Auto. | Figure | |
| 5.7L V8 Heavy Duty | ||||
| C20/30 & K20/30 | Fed. | All | Figure | |
| G30 | Fed. | Auto. | Figure | |
| P20/30 | Fed. | All | Figure | |
| P30 | Calif. | All | Figure | |
| P30 | Calif. | Man. | Figure | |
| G30 | Calif. | Auto. | Figure | |
| 6.2L V8 Diesel | ||||
| C10/20 | Fed. | All | Figure | |
| G20 | Fed. | All | Figure | |
| C10/20 & K10/20 | High Alt. | All | Figure | |
| G20 | High Alt. | All | Figure | |
| C10/20 & K10/20 | Fed. | Auto. | Figure | |
| 7.4L Heavy Duty | ||||
| C20/30, K30 & P30 | Fed. | All | Figure | |
| P30 | Fed. | All | Figure | |
| C20/30 & K30 | Calif. | All | Figure | |
| P30 | Calif. | All | Figure | |