I have a 1994 Jeep Grand Cherokee Laredo 4×4 4.0L 6cyl with 169+k miles. Automatic transmission failure in Nov. 2020. Repaired. Failed again within the hour out of shop. Replaced with comparative milage, tested used tranny December 2020. Minimal in-town driving since due to disability. Open highway distance driving yesterday. Failed again within an hour.
Transmission Temperature is High
Symptoms always the same: sensing minor shift delays after vehicle warms up to 200° range, high RPMs on open highway, vehicle refuses to move once stopped for traffic signs/lights, requires shutting down engine to cool off before tranny will re-engage to ‘limp’ a short distance before failing again. Works fine after vehicle fully cooled. Tranny fluid checks full & clean. Thermostat changed in Dec. No evidence of built-in radiator/tranny oil coolant leakage. I suspect either a tranny electrical problem or failure of the built-in tranny oil cooler. Considering having external mounted tranny oil cooler with fan installed because this consistently seems to be a heat-induced problem. IDK if it matters, but the part-time 4WD is only rarely engaged, works fine when used & has not been tested during any failure. Your thoughts please?
The first thing I would is look at the transmission fluid color. If the color is fresh and clean without a burnt smell I would lean toward an electrical cause over mechanical. Transmission Temperature can cause some serious damage.