Early KL Cherokee 9-speed had severe hunting and refusal to upshift. By 2018, major TSB updates improved behavior significantly but shudder at 30–45 mph is still possible.
Test the transmission extensively — all speed ranges, light throttle at highway, stop-and-go, and parking lot maneuvers. Any hesitation, hunting, or refusal to shift = transmission issue.
Est. cost: $350–$600 fluid + calibration / $4,500–$7,500 transmission replacement
Source: ZF 948TE revision history