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Are Rebuilt Auto Parts Good As New?

by Larry Carley copyright

Rebuilt auto parts have long been a popular alternative to new ones because they save money. Most rebuilt parts sell for 25 to 40% less than their new counterparts, so rebuilt starters, alternators, carburetors, water pumps, clutches, brake calipers, master cylinders, steering racks, FWD axle shafts, fuel injectors and electronic control modules are often preferred to new parts to lower repair costs.

Yet in spite of the potential savings, some buyers are reluctant to accept rebuilt parts and insist on new parts. With some, the issue is quality. They may not be convinced that rebuilt parts are as good as new ones. They may think rebuilt parts are nothing more than a "cheap" fix that won't hold up. Maybe they have had a bad experience with rebuilt parts before and do not want to take another chance. With others, it is a mindset that won't accept anything less than original equipment quality. They willingly pay more for a brand new OE part because they believe in the reputation of the OE supplier. There is also the issue of "direct fit." Some people do not want replacement parts that do not look or fit exactly the same as the original.

Are rebuilt parts really as good as new? Do they provide good value for the money? They can, but some may not be the bargain they seem to be.


Many rebuilt parts are as good as new, and some may even be better than new. You usually get what you pay for. Quality runs the gambit from bargain priced rebuilt parts that have been cleaned and "reconditioned" with a can of spray paint ("spray & pray" rebuilds) to ones that have been completely remanufactured to exacting OE standards and contain a high percentage of new parts. In some instances, the replacement components in the rebuilt part may even be more durable or perform better than the original.

As for quality, every rebuilder today is keenly aware of its importance. Most rebuilders strive to build the best parts they can so their customers will receive good value for their money. Rebuilders know that if they do not keep their customers happy, their customers will buy from their competitors. So keeping warranty returns down has become just as important as keeping the pipeline filled with product.

But quality costs money, and quality-conscious rebuilders are under considerable price pressure these days from jobbers and retailers who demand rock bottom prices. The buyers of these kind of parts are primarily interested in price, not quality. They want a part that works but are willing to trade OE quality for a lower price. And as long as they believe they are receiving good value, they will settle for less than the best. The question is whether or not they are really receiving good value. If a part lacks durability and fails in a few thousand miles or less, where is the value? Or if it does not perform the same as the original, was it worth the savings?

Sad to say, not everyone understands these differences. Many consumers do not have the slightest idea of what they are buying. All they know is that they need a starter, alternator, water pump or whatever. To them, a rebuilt starter is a rebuilt starter. But as we all know, there can be huge differences in quality and workmanship between a brand that painstakingly remanufactures their products to OEM specifications and one that takes as many short cuts as possible to keep the price down. Yet both may look the same on the outside even though it is an apples to lemons comparison. The only difference the consumer sees is the price tag. So unless someone explains the difference, or unless the person has been burned before on a cheap quality replacement part, he will usually buy the one with the lowest price thinking it is a good deal.

If all you want is a cheap fix and you are not overly concerned about reliability or performance (maybe because you are selling or trading your car), you can probably get by with the cheapest part you can find. On the other hand, if you want a part that is going to work properly and hold up the same as or better than the original, don't waste your time or money on cheap no-name bargain-priced parts. Buy a quality name brand part that will hold up and is backed by a warranty.


In some instances, the only part that may be available for a particular application is a new one. This may be the case if a vehicle is too new or if it is a limited production model. Finding a rebuilt electronic rack & pinion steering unit for an Accura NSX would be like finding the proverbial needle in the haystack. There might be a couple out there somewhere, but the odds of finding one without a lot of phoning and searching are slim. So if you can't locate a rebuilt part, new may be your only option.

On the other hand, rebuilt parts are often the only ones that are available for many older vehicles. Once a vehicle reaches a certain age, the new car dealers discontinue stocking parts and the OE channel of distribution dries up. That leaves the aftermarket to supply the parts.

Carburetors are a perfect example. How many new car dealers still stock carburetors today? None. Carburetors are an obsolete part. Yet there are still a lot of older cars and trucks with carbureted engines that may need a replacement carburetor. The primary source of supply for these carburetors is now the aftermarket and salvage yards. Overhauling a used carburetor can be risky because of worn throttle shafts, warped housings, etc., so the best option is to go with a rebuilt carburetor that is backed by a warranty.


Rebuilders are as diverse a group as any you will find in the aftermarket. They have different philosophies about how parts should be rebuilt and what constitutes good value for their customers. Some insist on calling their products "remanufactured" rather than rebuilt to denote a higher level of quality. The exact meaning of remanufactured is not easy to define, however, because each remanufacturer defines it differently. But generally speaking it means disassembling parts down to their basic components, replacing worn or failure-prone components and restoring the rest to OE standards before assembling the components to make a finished product.

Unfortunately, there are no universally agreed upon standards by which rebuilt parts can be compared to one another or to new parts. Rebuilders can't agree upon common standards because they all have their own ways of doing things. To some, a rebuilt part is one that has been restored to functional utility. To others, a part must be reconditioned to original equipment specifications.

When rebuilding an alternator, for example, one rebuilder may replace diodes only if a failure has occurred. But another may automatically replace all the diodes with ones that are more durable to improve reliability. One rebuilder may do nothing to the armature commutator other than to clean it up while another always recuts the commutator on a lathe to minimize runout for smooth high rpm operation. One rebuilder may reuse slip rings while another replaces them or resurfaces them on a lathe to minimize runout. Some rebuilders do not full-load test their alternators for fear of damaging their units while others will always full-load test each and every unit to make sure they meet specs and won't fail.


Regardless of their philosophical differences, rebuilders fall into one of several categories based on size. There are the small "custom" shops that serve a local clientele and primarily overhaul parts that are brought to them by their customers. They often work directly with repair shops and jobbers, but may also be willing to rebuild your old part if you bring it to them. They may keep a small inventory of ready-to-go units on the shelf, but are primarily accustomed to overhauling a customer's unit when it is brought into their shop. This type of rebuilder is usually quite flexible (they can handle the odd-ball jobs) and may even do installation work.

The small custom rebuilder often subscribes to the "fix-it" philosophy of rebuilding. They test a part, figure out what is wrong with it, fix it and return it to the customer. Only those components that are obviously defective or worn are replaced.

The next category is the regional rebuilder. This type of rebuilder may sell direct to installers and jobbers, but will also market their products through warehouse distributors and possibly even retail chains. The regional rebuilder likely started out as a custom shop that expanded their market by catering to a broader geographical area. They enjoy many of the benefits of a larger scale operation (lower per unit costs) but may not be as flexible as a small custom shop in being able to take in anything and everything. Some units may still be rebuilt on a one-for-one basis, but chances are the regional rebuilder is buying cores in bulk and process batches of parts at a time.

Then there is the national rebuilder. This type of rebuilder is geared to produce parts in volume for marketing to warehouse distributors and national accounts. They run large numbers of parts through their remanufacturing process in batches (though that is getting harder and harder to do these days because of parts proliferation), and will typically intermix and reassemble parts from different cores.

The regional and national rebuilders typically share the "remanufacturing" philosophy of rebuilding. They process parts in batches using cores from various sources, so individual components are processed on production lines in much the same way as new components are assembled by a new parts supplier. Remanufacturing puts more emphasis on building parts to OE specifications rather than fixing individual components that are worn or defective.

This is not to say that bigger rebuilders are necessarily better rebuilders. Even so, large scale remanufacturing operations do have major advantages including the ability to afford more sophisticated test and reconditioning equipment. They also have the financial resources for advanced engineering capability and the technical know-how to keep abreast of rapid changes in product design.

Regional and national rebuilders also put a great deal of effort into quality control to maintain their reputation in the marketplace. More than one rebuilder has lost a national account because of warranty problems. So there is an ongoing effort to constantly improves processes and product, and to make sure that every part that goes out the door is 100% perfect.


Many rebuilt parts today carry extended warranties instead of the usual 90-day warranty. It is not unusual to find products backed by a 1-year, 2-year or lifetime warranty. Labor is often the biggest part of the repair job, which the warranty may or may not cover. So one thing that should also be considered in addition to quality of the product itself is the quality of the warranty coverage.


Rebuilders as well as suppliers of new parts say a high percentage of "defective" parts that are returned under warranty have nothing wrong with them. The more complicated the part, the higher the return rate and the higher the percentage of "no faults found."

Charging problems are often blamed on the alternator, which may or may not be the cause of the fault.
When a rebuilt alternator is installed and fails to charge the battery, the is returned to the parts store
because it is thought to be "defective". The real problem may be a bad battery, loose or corroded battery cable connections
or a problem in the wiring harness, charging control circuit or an external voltage regulator.

Installers often blame "defective" replacement parts for their own mistakes. If a part is damaged during installation, is not installed correctly or did not need to be replaced, the technician may blame the replacement part rather than his own mistakes when the part does not work or fails to solve his problem.

The actual return rate for most rebuilt parts is typically less than two percent, which is on par with that of most new parts. Some parts, such as clutches, can be easily damaged during installation if the installer is careless or uses the wrong procedure. So it is important to place the blame where blame is due.

The real problem, they say, is "installer error." Installer error can occur for a number of reasons. On a clutch, for example, it is possible to damage the clutch if the transmission is allowed to hang by the input shaft. The weight of the shaft can bend the clutch plate causing release and engagement problems. So care must be taken to support the weight of the transmission until it can be bolted in place.

A remanufactured engine can likewise fail if the lubrication system is not primed prior to the initial startup. If you fail to adjust the timing correctly, don't get the cooling system completely full of coolant, misroute wires or vacuum lines, etc., you can create all kinds of problems for the new engine.

An engine that fails to crank because of a "bad" starter may in fact not have a bad starter. The real problem may be nothing more than a bad ground strap, battery cable, solenoid, ignition circuit, etc. But if the real problem is not correctly diagnosed, the replacement starter won't crank the engine any better than the original.

Rebuilt alternators can be easily ruined by failing to recharge a rundown battery. The alternator is designed to maintain battery charge, not to recharge dead batteries. The added strain of trying to revive a dead battery may overtax the unit causing it to overheat and fail.

The same goes for such high tech components as powertrain control modules (PCMs). An engine performance problem may be blamed on the computer because a technician does not know what else to do. So he replaces the PCM only to discover the original problem has not been fixed. Accurate diagnosis, therefore, is absolutely essential when replacing high tech components.

The bottom line is that rebuilt parts can and do provide a cost-effective alternative to buying new parts. Professional installers are usually aware of the quality differences that are available and won't take a chance on anything that does not meet original equipment specifications. But consumers don't always understand this and often need to be educated as to what the differences are.

rebuilt auto parts Related Articles:

Alternator Testing

Alternator Troubleshooting

How To Replace an Alternator

Fuel Pump (electric)

Fuel Pump (mechanical)

Fuel Pump Warranty Issues


Water Pump Diagnosis

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