One of the most critical components in a car’s engine compartment is its exhaust system. It’s a complex assembly that is constantly in contact with heat and pressure from the under-the-hood action. It is under extreme operating conditions such as corrosion, salt air, high temperatures and impact damage. And yet, like all things automotive, exhaust systems get old and worn down over time (the average age on most cars is 11 years). That’s why we recommend that you repair or replace your exhaust about once every four or five years. Sooner, if you drive in an area with adverse conditions. If you recently had some major work done on your car, you may have noticed that the mechanic replaced some parts.
This article explains why your exhaust might have been repaired or replaced during service. And what you should know before it happens again.
Exhaust Repair vs Replacement
There are two types of Exhaust Repair Reading on most cars today: stainless steel with a catalytic converter (the converter reduces smog-producing emissions by burning excess gases) or aluminised steel with no catalytic converter (known as an “expensive” system). There’s also a third type of system found mainly on European imports, made mostly of stainless steel. Still, without any high-temperature insulation or heavy ductwork across the front of the vehicle. The latter system works well in pre-1986 cars that don’t get driven much any more. Still, it’s used on some foreign-made luxury cars (such as the Audi 4000 and Ford Taurus X) because of its quietness.
There are pros and cons for repairing versus replacing an exhaust system.
An exhaust repair will usually take one to two hours and cost between $100 and $150 per muffler. Labour is about 50 per cent of that total. The downside: you’ll only get another year or so out of a repaired system before it needs attention again. And future repairs will be quite costly because you have to remove or replace all the pipes in the entire system each time. On average, motorists spend between $1,500 and $2,500 for a completely new system. They get a new system guaranteed for the car’s life. If you go this route, expect to pay around $100 per muffler on average. Labour runs about 50 percent of that total.
The best choice depends on where you live and how you use your car. The replacement is wise if your car spends much time idling in traffic. You will need replacement if it operates in stop-and-go cycles at low speeds (for instance, taxis). But if you use your car more for long-distance highway driving or hauling heavy objects, then repairing may make sense because the exhaust will heat up more during those conditions.
When Replacing Is Best
You’ll need an Exhaust Repair Reading replacement whenever any part of the system is damaged, weakened or excessively corroded. This includes leaks at the flex joints (which are connected by clamps), rusted out mufflers and tailpipes, broken hangers (metal supports that hold up the exhaust pipe) or any holes in the floor of the vehicle’s trunk area. A corroded converter also requires replacement because you cannot repair it due to high temperatures and corrosion inside. This part is very expensive, usually $500 to $3,000 for a complete unit.
If you’re buying an entirely new system, here’s what you should know:
• Exhaust systems are made up of three sections that attach flexible “universal” joints that allow the system to expand under heat expansion. You’ll pay by the foot for this flexible piping, which can add up in a hurry.
• The converters are present between the engine and each muffler. They often require replacement after about 12 years because of overheating caused by clogged passages or erosion from high exhaust gas temperatures. The average cost is $500 to $3,000 plus labour. Still, you can find universal conversions at some shops for as little as $200. Shop around for the best price; auto supply stores such as AutoZone and Advance carry universal converters (see the chart).
• New catalytic converters will work with your existing mufflers (providing they’re similar), so don’t worry about that when shopping for a new system.
• The vehicle manufacturer may offer the best price on a brand-new complete system. If not, call several local wrecking yards and ask them what brands they stock (Allied, Walker, Flowmaster). Also, ask for the price on each. When you get several responses, it’s easy to compare. Also, make sure the mufflers meet federal requirements. Any good parts store will tell you if they do or don’t by checking your VIN (usually found under the hood).
• Muffler shops usually charge about $100 per muffler (before installation) and 10 hours’ labour for an entirely new exhaust system from scratch. Add about 80 per cent for installation charges because it will need not much work to put in a new system.
• New replacement systems usually include the entire exhaust from front to back and come with a 3-year or 36,000-mile warranty (check the packaging and warranty book for details).
When Repairing Is Best
Repair is cheaper than replacement; however, repairs generally only last another year or two before you’ll have to repeat the process. You can repair most MOT Reading leaks at rubber hangers (universal joints). This is present between each muffler and the part of the exhaust pipe that attaches to it. A universal joint is easy to fix by hand if it’s leaking. However, if there’s any question it needs, consult with your mechanic because it requires skill with a torch.
The best way to fix leaks at rubber hangers is only to replace the flex joint between each muffler and pipe. Especially if you’re unsure when that was done. Replacing this joint in good condition will cost about $75 in parts, or twice that for both joints because several are usually involved. If your flex joints are bad, replace them all with universal joints along with the entire system (see “Replacement Is Best” above).