In Focus: Thexton THX108 DEF-CHEK Professional Tester

May 10, 2016
Tool tests diesel exhaust fluid (DEF) concentration for heavy duty trucks.

The Thexton THX 108 DEF CHEK Tester is a Diesel Exhaust Fluid (DEF) tester that features urea concentrate testing and temperature compensating discs that test DEF, hot or cold. If mixture is 0.7 percent off, the manufacturer suggests replacing DEF and identifying why concentrate is off. If the DEF concentrate is not correct, injectors may become clogged and DEF will not work properly.

Selling Points

  • Tests Urea concentration in the DEF tank of heavy duty vehicles.
  • If mixture is 0.7 percent off, manufacturer suggests replacing the DEF fluid.
  • Temperature compensating discs test DEF hot or cold.
  • Tester helps avoid costly repairs.
  • Failure to test the Urea will result in lost performance in the vehicle.

Feature and benefits

The THX 108 DEF CHEK Professional Tester provides the diesel vehicle (car, truck or heavy duty vehicles) the ability to check the DEF tank in a cost-effective manner. 

The THX 108 DEF CHECK Professional Tester is an accurate measurement tool to test the Urea content in the vehicle's DEF tank.

The THX 108 works with any vehicle that has a DEF tank installed. In 2009, the EPA mandated that all diesel vehicles 2010 and newer be required to have a DEF tank installed.


The THX 108 DEF CHEK Professional Tester is used to check the Urea content in the vehicles DEF tank. The THX 108 will provide technicians with a cost-effective way to test the Urea content.


The THX 108 DEF CHEK Professional Tester is manufactured in the USA. The Product is constructed of a plastic tube, polypropylene plastic disc and rubber top. The THX 108 allows for testing of the Urea content in the DEF Tanks on diesel vehicles. The THX 108 weights less than 2 lbs.

Storage and display

The THX 108 DEF CHEK Professional Tester is packaged in a see-through shrinkwrap package. Hanging the THX 108 on display in the tool truck or bringing it inside at stops to show shops that work on diesel vehicles is the best method for exposure

Suggested retail price


For more information

Thexton Manufacturing Co.

(800) 328-6277

[email protected]

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