What Causes Transmission Overheating?
2 Answers
Reasons for transmission overheating: 1. Insufficient lubricating oil in the transmission or use of lubricating oil with incorrect specifications; 2. Overly tight bearing assembly; 3. Overly tight gasket and washer assembly; 4. Excessively small meshing clearance of newly replaced gears. During an on-road stop inspection, touch various parts of the transmission housing by hand to check temperature. If the hand can tolerate the heat, the oil temperature is normal; if not, it indicates an overheating issue. To confirm transmission overheating, first check the lubricating oil level. If insufficient, replenish according to specifications; if the oil is too thin or deteriorated, replace it; if dry friction is caused by overly small assembly clearance (such as when bearings are assembled too tightly or overheating occurs near the bearing seat), conduct separate disassembly inspections and reassemble according to standards.
I found that transmission overheating is mainly caused by oil issues and an ineffective cooling system. Transmission oil acts like a lubricant; if it's insufficient or dirty, it can't dissipate heat effectively, leading to a temperature spike. During inspection, I first check if the oil level is normal, and if it's below the standard, I add the appropriate fluid. A clogged cooler due to dust or debris is also a common cause, and regularly cleaning the cooling fins can prevent many problems. Heavy-duty driving or prolonged uphill climbs increase the transmission's load, generating more friction and heat buildup, so it's advisable to control speed and avoid overloading. If overheating becomes severe, the transmission may produce unusual noises or even lead to a breakdown, so timely repairs can save significant costs. Preventive measures include changing the transmission oil every two years and keeping the cooling system unobstructed.
