At its 1988 launch, the fourth-generation C/K pickup trucks shared its five-engine powertrain offering with the R/V series. On 1500 series vehicles, a 4.3 L Vortec V6 was standard, with the options of a 5.0 L V8, 5.7 L V8 and a 6.2 L diesel V8. On 2500-series and 3500-series vehicles, a 5.7 L V8 was standard, with a 7.4 L V8 and 6.2 L diesel V8 as options. The 4-speed manual of the previous generation was carried over (for 3500-series trucks), with GM introducing a 5-speed overdrive manual (for 1500 and 2500-series vehicles). A 4-speed overdrive automatic was an option on all engines (for 1500 and 2500-series vehicles); a 3-speed automatic was also offered (and was the sole automatic for 3500-series trucks).
