The seriously broken vehicle that arrives by tow truck is not often something a garage owner celebrates even if the service bays may be open and the mechanics are sweeping the floor instead of performing repairs. These jobs can be especially challenging when the customer and vehicle are new to the business.
Broken cars do not talk and many times owners of broken cars don’t talk either (maybe they don’t know). Seriously broken vehicles need engines rebuilt or replaced. Seriously broken vehicles need transmissions rebuilt or replaced.
Mechanically failed engines and transmissions typically require replacement with new or rebuilt units. Many shops do not repair these units in house. They are not equipped to do these jobs cost effectively. A basic four cylinder engine overhaul requires at least thirty hours of labor.
Catastrophic engine failures are uncommon. Technology is that good. Most failures are the result of neglect. You still have to change your oil and keep the level up. You still have to keep your vehicle filled with engine coolant. Does late night television still eschew the use of magical potions that will allow your engine to run without both coolant or engine oil? Just remember these products are still snake oil.
When the vehicle cannot be driven into the shop under its own power there are many questions that remain unknown.
A road test is out of the question. What is the overall condition of the vehicle? Replacing the engine is a given that involves thousands of dollars. How many other vehicle systems are involved in the failure? Did the engine fail by overheating? Did the electric cooling fan fail? Is the radiator clogged? Is the exhaust system restricted? Is the fuel pump weak?
The process to verify these other systems is only viable (cost effective) when performed on a running vehicle. Finding these problems after a new engine is in place is mandatory but can add significantly to the price of the repair. The days of thousand dollar fuel pump replacements and five hundred dollar radiator replacements are here.
Once the engine is up and running the reason for its failure may be readily apparent but it might not be. Further diagnosis may follow.
Worst case scenario the vehicle needs a new transmission as well.
Transmission failure while different from engine failure has its own complications. Late model vehicle automatic transmissions do fail from abuse and normal wear and tear but more than ever they can fail as a result of problems with other systems.
Automatic transmissions used to have all their control systems contained within. Not any more.
Governors have been replaced with a speed signal from the anti-lock brake system. The load signal is no longer from a cable or vacuum hose but instead information from the engine’s mass air flow sensor or throttle position sensor. How long was the owner driving with the ABS light on or the check engine light on?
Again the ABS system and engine control system cannot be thoroughly tested without a vehicle that moves under its own power. Until that transmission is repaired and/or replaced evaluation of the other systems is not cost effective or definitive.
So the vehicle that is pushed in the door of the shop is many times a big unknown. The decision to spend big dollars on replacing a major component like a transmission or an engine has to be done knowing that hidden costs are involved and very likely. I do not like being the bearer of these surprises. Hopefully, my new customer will understand. Maybe not?
Trail’s Ron Nutini is a licensed automotive technician and graduate of mechanical engineering from UBC. He will write every other Thursday. E-mail: email@example.com