-Low transmission fluid: If the transmission fluid level is low, it can cause the gears to grind when shifting. Check the transmission fluid level and add more fluid if necessary.
-Worn transmission mounts: The transmission mounts are responsible for holding the transmission in place. If the transmission mounts are worn, it can cause the transmission to move around, which can cause the gears to grind. Inspect the transmission mounts and replace them if they are worn.
-Damaged gears: If the gears in the transmission are damaged, it can cause the gears to grind when shifting. This can be caused by a variety of factors, such as excessive wear and tear, or an impact to the transmission. If the gears are damaged, they will need to be replaced.
-Faulty shift linkage: The shift linkage is the mechanism that connects the gearshift lever to the transmission. If the shift linkage is faulty, it can cause the gears to grind when shifting. Inspect the shift linkage and replace any worn or damaged parts.