LandCruiser Transmission Sensor Issue

Sounds like a classic case of a failing transmission oil temperature sensor throwing your LandCruiser into protective mode. The slipping and rough shifting are definitely concerning. When the sensor malfunctions, the transmission control unit (TCU) receives incorrect temperature readings, which messes with the shift timing and pressure. Grinding noises can indicate internal damage due to improper lubrication or shifting. Before replacing the sensor, have you checked the transmission fluid level? Low fluid can cause similar symptoms, as the sensor might not be fully submerged and reading correctly.

Fluid level, huh? I haven't checked that yet, figured it was a sensor issue. Where exactly do I check the level on this thing? And what kind of fluid does it take?

On your LandCruiser, there should be a dipstick for the automatic transmission fluid, usually located near the back of the engine bay, close to the transmission itself. It'll likely have a bright-colored handle, often yellow or orange, marked for 'ATF'. Refer to your owner's manual for the exact location. As for the fluid type, Toyota usually specifies a particular ATF – it's crucial to use the correct one to avoid damaging the transmission. Again, your manual will tell you the specific type (e.g., Toyota Type T-IV or WS). That being said, based on your symptoms, especially the grinding, it's wise to take it to a workshop for a proper diagnosis. Low fluid might be the culprit, but there could be underlying damage from running it low.

Thanks for the detailed info! I checked the fluid, and it was indeed low. Topped it off, but the problem persisted. Took it to the workshop as you suggested, turns out the sensor was faulty AND there was some minor wear inside the transmission. Got the sensor replaced and the transmission serviced for 365€. Shifts like new now!