Bottom Line
Rebuild or replace?
Repairing worn parts isn't your only option anymore

By Jeff Barker
contributing writer

 

Over time, we have seen the evolution of truck designs and their components. In most cases, it can be argued that newer components are designed to last much longer than they did 20 years ago, but let’s face it, they still wear out eventually.

Here are a few truck components that you are typically better off replacing instead of repairing because of many practical reasons, including downtime, warranties and reliability:

A/C compressors

In years past, many of us got used to seeing those old York and Tecumseh air conditioner compressors on our trucks, which were also used in many automotive applications as well. They worked great, but they were notorious for having front seal leaks and compressor clutch failures.

It used to be easy enough to just replace the input shaft seal and/or the compressor clutch assembly instead of the entire compressor, but few of these compressors are still around.

Newer model compressors hold up longer in over-the-road applications. When something eventually does go wrong with them, however, it’s more practical to replace the entire compressor assembly. The assembly usually comes with a new compressor clutch already mounted up and ready to go.

If the clutch assembly fails, chances are the front seal may be toast. It makes sense to change out the entire assembly instead of dealing with the agony of that front seal failing and leaving you without a working air conditioner out in the middle of the Mojave Desert during the summer.

Condensers, evaporators and heater cores

Air conditioner condensers experience much higher operating pressure nowadays with the use of R134a refrigerant and often a much smaller surface area. In the past with the old R12 systems, we used to be able to break out the torch and repair condenser cores, but not anymore. A solder repair over a crack or leak may hold up for a short time on an R134a system, but not for long. It makes sense to just replace this item.

With evaporators and heater cores often being difficult for even the most seasoned mechanic to get to, the effort required to do this job is enough to justify not reusing one. Besides, vapors from antifreeze or leaking refrigerant can cause respiratory problems.

Engine water pumps

The decision to replace a water pump is a no-brainer. Besides, it often takes special shop equipment to successfully rebuild a water pump. Also, having a warranty on a part never hurts either.

If you have a truck that you intend to keep for a few years, it’s worth it to spend a few extra bucks for a new water pump instead of a rebuilt one.

Transmissions

Scheduled maintenance includes checking the oil level at every preventive maintenance interval and changing the transmission oil whenever it’s dirty or at the typical recommended 250,000-mile intervals. Otherwise, transmissions usually don’t require much attention unless they see a lot of grinding abuse.

Unless the transmission just needs an input shaft seal and bearing replacement or a clutch release fork assembly and bushings, it makes better sense to replace a troublesome tranny with a quality rebuilt unit. Transmission rebuilds and repairs are best left to those who specialize in that kind of work for many reasons. Also, the turnaround time to get yours repaired makes it more practical to swap it out for a rebuilt one so you can be back on the road much sooner.

Windshield wiper motors

Most wiper motors on trucks nowadays are electric and are more reliable than in years past. Unfortunately, like anything else on a truck, they do eventually wear out or fail.

Unless it’s something simple and obvious, such as soldering a loose electrical connection, wiper motors should never be repaired and reused. This is a safety item and not an area to cut corners with to save a few bucks.

Radiators

Almost anyone who has been around the truck repair industry for a while knows that it’s rarely practical to repair a truck’s radiator, especially since most trucks built in the past 15 years have radiators with plastic tanks on them. They work fine for a long time, but after about 750,000 miles the plastic tanks develop dry rot and can fall apart.

With the amount of vibration and abuse a truck radiator endures during its lifetime, the header area near the tubes can crack and burst open.

If a radiator fails, replace it. It would be worth the time to check with local radiator shops and get prices from them. I bought new radiators with metal tanks, which I like better, for my trucks and they were each about $200 less than their plastic counterparts – not to mention better quality units.

Brake valves and spring brake chambers

It used to be easy enough to replace diaphragms and other rubber parts in the brake valves and chambers. But nowadays, for a number of reasons, it’s more practical to replace the defective parts.

In-dash radios

Some days on the road are undoubtedly long. What’s worse is not having a working radio in the cab of the truck you’re driving.

Unless you have a serious high-end stereo in your dash, it often makes little sense to repair one because the repair bill is often as much as, or more, than the radio is worth. LL

 

Editor’s note: This article is for information purposes only. If you’re not sure about performing the work yourself, it’s advisable to seek the help of a competent professional.

Jeff Barker is an OOIDA member and a former certified diesel mechanic. He may be reached at truckmaintenancestuff@yahoo.com.

Aug/Sept Digital Edition