What to check in a truck's cooling system before the summer to avoid breakdowns in the middle of the campaign

June 2, 2026

With the arrival of summer, many commercial vehicles start working under particularly demanding conditions: high external temperatures, long operating hours, large loads or dusty and dirty environments. 

In this context, any small anomaly in the cooling system can lead to overheating, loss of performance or even unexpected breakdowns.

Therefore, a preventive check-up before the hottest months of the year is essential to ensure the reliability of the vehicle.

Some of the more important points that should be checked are:

• The condition of the viscous clutch and the correct fan activation

• The level and condition of the coolant (without oil and oxide)

• The presence of abnormal vibrations or noises

• The condition of the fan clutch bracket and possible clearance

• The connections and electronic components through diagnostics

• The accumulation of dirt in air passage areas such as the radiator

• The balancing and condition of the fan

• The review of additional components such as belts, thermostat, etc

• The system operation under load

In agricultural environments, on roads, at construction work or in quarries, the cooling system is constantly operating close to its thermal limits. In these situations, a slight loss of efficiency can lead to significant temperature increases.

In addition, many problems appear progressively and only become noticeable when the vehicle is working under maximum demand, which makes them very difficult to detect during normal use.

For this reason, at Cojali Parts we pay special attention to aspects such as fan balancing, the functional control of viscous clutches or the validation of the thermal behaviour of each reference. These processes ensure reliable operation even under particularly severe operating conditions.

Prevention remains the most effective way to avoid costly breakdowns during peak workload months.