DEF is easy to contaminate, and fortunately, it’s also easy to test. Check to be sure that your customers’ DEF is up to spec with these simple tests.

Nick and Lemmy check out a flex plate from an imported Japanese automatic transmission with very few miles under its belt.
Throw a set of these resettable “fuses” in your toolbox.
A defective harmonic balancer can affect the accuracy of ignition timing readings or a defective harmonic balancer can damage the crank. Which technician is correct?
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Auto care news and advice you can use.
Can independent repair shops benefit by offering mobile service to an increasingly immobile America?
Two solutions for yellowed, hazy headlights.
They look the same, but serve different roles. Here are the very specific scenarios where the lesser-known parallel connector shines.
Shop Press’ Andy Greaser breaks down permanent antifreeze and today’s coolant for your vehicles.
As new cars and trucks, especially EVs, get heavier than ever, it’s important to check your lift’s rating and condition.
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Auto care news and advice you can use.
A fluid transfer pump is the cleanest and easiest way to fill a differential, transmission or transfer case with its necessary fluid.
As dashboard cameras become more common, repair professionals should know how to deal with them.
Reverse is an innovation that’s easy to take for granted—but it was a revolutionary addition to the automobile.
“Rebuild in a can” is not the right way to fix the tool, but it will get you by until you can repair it correctly.
Microtransactions spark unexpected microaggressions.
Why wouldn’t your shop purchase a few of these?
Two technicians are examining a tapping sound coming from a V6 engine. See who has the correct response about what’s causing the noise.
We’ve all heard the expression “buy once, cry once,” and for some auto parts, those are words of wisdom. For others, it might be an unnecessary expense.