The electronically controlled GM Hydra-Matic 6L80 six-speed automatic transmission has a low first gear and two overdrives. Its ratios are: First, 4.02; Second, 2.36; Third, 1.53; Fourth, 1.15; Fifth, 0.85; Sixth, 0.67. These ratios will allow the YJ to crawl in the rocks and cruise on the highway. The 6L80 is taller and slightly shorter than a 4L60. We used the OE torque converter.