P2714: How to Diagnose & Fix — Pressure Control Solenoid D Performance/Stuck Off

The ZF 8HP70 eight-speed automatic transmission used in the L494 Range Rover Sport develops valve body and mechatronic unit faults. Symptoms include harsh shifts, delayed engagement, and occasional limp mode. The solenoids in the valve body wear and cause improper fluid routing. The transmission adapts by increasing line pressure, which accelerates wear on the clutch packs.

The GM 6L50 6-speed automatic transmission in V6-equipped STS models is prone to overheating and developing harsh shift quality. The transmission fluid cooler is undersized for the vehicle weight, and the valve body solenoids degrade from heat cycling. Fluid darkens rapidly, and shift quality deteriorates with delayed or slipping 3-4 and 5-6 upshifts. The torque converter clutch also fails prematurely from heat damage.

First-generation Enclaves (2008-2017) use the 6T70/6T75 6-speed automatic, whose stamped-steel 35R wave plate can crack at the teeth after enough shift cycles. When it fractures, the transmission abruptly loses 3rd, 5th, and reverse gears, and debris can damage the valve body, drums, and torque converter. Failure typically occurs in higher-mileage 2008-2012 builds.

Owners of the 300-series Land Cruiser and closely related TNGA-F Toyota/Lexus models have reported delayed engagement, low-speed hesitation, or abrupt 10-speed automatic shifts, especially when cold or during rolling stops. Toyota service literature for related powertrain calibration concerns points to software logic rather than hard-part failure in many cases. Complaints typically describe inconsistent throttle response paired with a sudden downshift or lurch.

The VT40 continuously variable transmission fitted behind the 1.5L turbo from the 2019 model year onward develops a sticking clutch regulator valve in the valve body. Pressure to the forward clutch falls off, the car shudders or bangs on the 1-2 engagement, delays going into drive after a cold start, and eventually sets P2714 (pressure control solenoid D stuck off). Forum teardowns report damage to the forward clutch piston and wear in the primary pulley bearing bore by the time the code appears, so the valve is only the first domino. This is a distinct unit from the 6T40 and 9-speed step automatics used elsewhere in the nameplate and its failure signature — a slip and flare with no gear change, rather than a harsh shift — should not be merged with theirs. Reports cluster after roughly five years in service.