Fluctuations in Mileage When Towing a Car with a Motorhome
The concept of tracking mileage when a car is transported in a motorhome can sometimes lead to confusion, especially for those who are accustomed to traditional driving methods. The question often arises: 'Does the mileage on a car increase when carried by a motorhome?' This article aims to clarify the situation based on various scenarios and technologies used in modern vehicles.
Understanding the Basics
When a car is carried by a motorhome, its actual mileage does not increase in the traditional sense. The car is not being driven, and thus, its engine is not engaging in the combustion process to produce movement. However, the motorhome itself will consume more fuel due to the added weight and increased aerodynamic drag of carrying the car. This extra fuel consumption may be perceived as a decrease in fuel efficiency, leading to a decrease in the motorhome's mileage record. It is essential to note that the primary vehicle (the motorhome) is not designed to optimize mileage while carrying an additional load.
Mechanical and Electronic Odometers
The impact of towing on the odometer depends largely on the type of vehicle and its odometer system. In modern vehicles with computer systems, the electronic speed sensor requires a voltage reference to send pulses back to the ECM (Engine Control Module) or spedometer. As long as the ignition is off, these systems do not add any additional mileage. In older cable-driven speedometers, the odometer will continue to accrue mileage as long as the driveshaft is connected to the drive train/axle/rearend.
Flat Towing vs. Towed by Dolly
Towing a car can be done in different ways. For instance, when flat towing a pickup truck, the mileage often registers because all four wheels are spinning, meaning the odometer is working. However, with a forward-wheel drive (FWD) van towed with a tow dolly, the mileage does not register since the front wheels are not spinning. The transfer case in the Jeep also plays a significant role in this scenario. When towing a Jeep, the transfer case is often shifted to neutral, which disconnects the transmission from spinning drive shafts, preventing any additional mileage on the odometer.
Conclusion and Summary
In summary, the mileage on the car being towed remains unchanged as it is not engaged in the driving process. However, the fuel efficiency of the motorhome may decrease due to the additional load. The odometer reading is directly influenced by the condition of the wheels and the transmission system. For modern vehicles with electronic systems, the mileage may not increase when the car is not driven, while older mechanical systems may still show increased readings.
Regardless of the method of towing, it is crucial to consider the impact on fuel efficiency and mileage when planning long trips with a motorhome or any other towing situation.