Hand pump that pressurizes a cooling system to 4-30 PSI so you can find a leaking radiator, heater core or internal ATF cooler.
Pink, frothy transmission fluid or a coolant bottle that looks like strawberry milk usually means one thing on a car or truck with the ATF cooler built into the radiator: the cooler inside the tank has cracked and coolant and ATF are mixing. The OEMTOOLS 27069 is a hand-operated cooling system pressure tester with a 4 to 30 PSI gauge that lets you prove the leak, find it, and confirm the repair before you fill a rebuilt or replacement transmission and send it back down the road.
On many GM and Ford vehicles the transmission cooler is a tube bundle sitting in one of the radiator tanks. When it leaks, coolant ends up in the transmission and ATF ends up in the coolant. Pressurizing the cooling system to cap rating and watching the needle tells you whether the system holds. A needle that drops with no drip under the car means the coolant is going somewhere internal: the heater core, a head gasket, or the trans cooler.
Coolant in ATF is not a small problem. As GEARS Magazine explains, water and glycol break down the fluid, attack the friction additives, and can flash to steam at the clutch surfaces and separate friction lining from its steel backing. A rebuilt unit installed behind a leaking radiator cooler can fail the same way the old one did.
With the engine cold, take off the radiator cap, clamp the included coupler onto the filler neck and pump to the pressure stamped on the cap; most factory caps fall in the 15 to 18 PSI range, inside this gauge's 4 to 30 PSI scale. Do not go past the cap rating. Hold it 10 to 15 minutes and watch the needle. Then pull a fluid sample and compare it with our ATF color and smell chart; coolant in the fluid separates a trans cooler leak from a heater core or head gasket. Our cooler flush after failure guide covers what to do with the cooler circuit once you know.
The 27069 includes the steel pump body, the 4 to 30 PSI gauge, the hose, and the standard radiator filler-neck coupler, packed in a blow mold case about 14 x 9 x 3.5 inches. It is the pump only: vehicle-specific neck and coolant bottle adapters for many imports are separate, and the pump accepts the regular OEMTOOLS cooling system adapters. If you want adapters and vacuum refill in one kit, see the OEMTOOLS 24444 coolant vacuum refill and pressure tester kit. More testers are in our diagnostics category.
The tester weighs about 3 pounds, has a steel body, and carries a limited lifetime warranty from the manufacturer.
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It shows whether the cooling system holds pressure. If the needle drops with no external leak, check the ATF for coolant contamination; coolant in the fluid points to the in-radiator cooler rather than a heater core or head gasket.
To the rating stamped on your radiator cap, typically 15 to 18 PSI on factory caps. The gauge reads 4 to 30 PSI. Going past the cap rating can damage a heater core or radiator that was fine.
It comes with the standard radiator filler-neck coupler. Vehicle-specific neck and coolant bottle adapters are separate; the pump accepts the regular OEMTOOLS cooling system adapters.
Coolant in ATF breaks down the fluid and can delaminate clutch frictions. If the old transmission failed from coolant contamination, a new one installed behind the same leaking radiator cooler can fail the same way.
Replace the radiator or cooler, flush the cooler lines, and replace contaminated fluid. Units that ran on coolant usually need a rebuild because the friction material is damaged.
