how to replace the oil cooler on my truck. the temp indicator goes hi on 2008 Ford F-250 Super Duty

than back to normal when i reduce speed. is the problem the oil cooler?

2 answers
check for debris in front of cooler blocking good air flow. Check behind as well, between a/c condenser, intercooler, and radiator. If debris is between those place it will interrupt air flow behind as well.
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