2.7 oil cooler failure

[Cooker]

Hi there.
Why would my rebuilt 2.7 be blowing BEHR oil coolers. Gone thru 3 in 20,000 miles.

Never a problem before the rebuild.

Thanks Wayne

[stownsen914]

How’s your oil pressure?
If it’s normal, look into whether the thermostat on the engine is operational. If it’s stuck in the “hot” position, cold oil could be going to the cooler during warmup under higher pressure than it’s designed to handle. You can test the thermostat for normal operation. They do fail sometimes.

[Henry Schmidt]

Faulty thermostat or excessive pressure when cold.
Properly rebuilt, the 2.7 could easily generate more oil pressure that safe at start up.
A few high pressure events will compromise the cooler integrity.