Engine oil cooler overheating, 88 Suburban

[sandybottom]

Hello everyone, new to to the forum, nice to be here!

I have an 88 Surburban, 4WD with a 350 TBI, the engine oil cooler got so hot while driving the other day it melted the front grill. Took a temperature reading with laser thermometer and on the cooler at it was at 300F !!! The engine was at 204 and the headers were 230, and transmission was about 208 all read normal range except the oil cooler.

So what's the cause of such a high temp in the oil cooler? Anyone aware of possible causes for this kind of heat?

Thanks!