The Dura-Lite™ Charge Air Cooler Tester-Kit™ is a specialized tool designed specifically for testing charge air coolers quickly and accurately. The tester measures the amount of pressurized air the CAC loses over a designated period of time. This will determine if the CAC is leaking or not. A leaking charge air cooler will rob performance, increase fuel consumption, and increase DPF regeneration cycles.
View the Dura-Lite Intercooler/ Charge Air Cooler (CAC) Tester-Kit Video
How to Check Charge Air Cooler for Leaks
Instructions for using Dura-Lite’s Charge Air Cooler Tester-Kit
Video Transcript:
Today I'm going to show you how to use the Dura-Lite leak down test kit for charge air cooler. This kit gives you a very quick efficient method of testing for leaks in your charge air cooler. If you are running with a leak, you are in jeopardy of losing horsepower, losing fuel economy, and prematurely blocking your DPF filter system.
This kit has rubber plugs in it which I'll show you how to use in just a minute starting at 2 ½” all the way up to 3 3/4”. Before inserting the rubber plug into the inlet or the outlet of your charge air cooler, make sure that the inlet and outlet are free and clear of any moisture or debris.
Once you have removed the piping from the charge air cooler you can select the appropriate size plug required for your application that's as simple as taking a plug, matching it up to the hole size, if it's too big take the next one down. Once you find the plug that fits you found the right size plug. In some cases, there will be a lot of room, and you might think the plug is too small but don't let that bother you, I've tightened this here 3 ½” plug just by hand and as you can see we've got it almost 4” in diameter.
Once you've removed the piping from your charge air cooler, take your assembled plug and tightening handle apparatus give it a quick little spin so that that plug expands just enough to make it snug. When you're inserting it in the inlet, make sure the washer is flush with the front of the inlet and continue to tighten by hand until it feels snug.
The next step is to use the safety clamps provided in the Tester-Kit. Place them over the handle and tighten the wing nuts up by hand until the notched portion of the clamp is sitting snug on the outlet of the charge air cooler make sure the bolts as well are flush up against the front of the charge air cooler.
The Dura-Lite gauge assembly is equipped with a pressure relief valve and a quick coupler and a Schrader valve, which is the same valve that's on your tires it simply snaps on to the open stem like so.
We are now on the cold side of the charge air cooler and as you can see, the handle on our test kit is being blocked by the overflow tank for the radiator that's not a problem, we do have coupler nuts which we use in these circumstances.
When assembling your rubber plug stem and washers, make sure to always use the nylon washer supplied with the test kit, and for a coupler nut that can deform that nylon washer I always put a 5/8" washer on top for protection. Then thread on either your handle or your coupler nut. We now have the plug with the solid stem installed on the cold side and we are ready to add air.
The rule of thumb is to pressure up to 30 psig for most Class 8 applications, then watch for a 5 psig drop in a 15 second window. In this application we have a Detroit powered engine and we have 30 seconds to watch for that 5 psig drop.
We'll start counting now.
I think that's around 30 seconds there, and this cooler looks like it's good to me. In my experience most coolers which fail, will fail well outside of the original equipment manufacturers leaked down rate specifications.
Like this cooler here I’m applying 120 psi of shop air, and I can't even get the gauge to read to 30 psig!
The really great thing about the Dura-Lite Tester-Kit is you can test any cooler while it's still on the truck in 20 minutes or less and ensure efficient operation of your vehicle. Keeping it on the road for years to come.
Heavy Duty Charge Air Cooler Tester
The Dura-Lite Heavy-Duty Charge Air Cooler (CAC) Tester is a professional-grade diagnostic tool designed specifically for testing the integrity of large intercoolers (CACs) used in the diesel engines of heavy trucks, buses, and off-highway equipment.
It’s an essential maintenance and troubleshooting tool for ensuring peak engine performance, fuel efficiency, and emissions compliance.
Dura-Lite produces one of the most trusted testing kits in the heavy truck industry.
Features:
- Tests CACs on or off the vehicle.
- Adjustable adapters fit a wide range of cooler sizes.
- Quick-connect fittings for fast setup.
- High-quality pressure gauge (accurate and rugged).
- Used by major fleets and OEMs worldwide.
- Identifies even tiny leaks that can cost 1-2 MPG in efficiency.
CAC Test Kit
You can buy a Dura-Lite CAC Tester-Kit online from one of our online stores.
The product is usually shipped the same day (if ordered before our cut-off time) from one of our strategically located, well stocked, Distribution Centers within the USA and Canada.
With our CAC Test Kit, testing your Intercooler will become as automatic as checking the oil and will give you confidence in knowing that your engine is performing at the required level.
Demand Excellence! Demand Performance! Demand Quality! Demand Dura-Lite!


