The cooler lines on my 99 were leaking and I hadn't taken the time to replace them. I needed to take it out of town this weekend so I decided to pull the cooler/lines and plug the ports so I wouldn't experience catastrophic engine failure on my trip. Then was going to order a cooler from L.S. this week and put it on next week when I got back. Two days and 60 miles after I plugged the cooler ports I notice that the beast doesn't have any oil pressure at idle. Further inspection reveals metal flakes in the oil. Did plugging the oil cooler ports cause this some how? I would think that it should supply the engine just fine without the cooler. It carried oil pressure after I plugged them, but it didn't peg the gauage as if it needed the cooler in place. Maybe it was just a coincidence that the engine suffered another failure at about the same time as my working on it, but I don't know. Anybody have any imput? Ever experienced this after plugging the cooler ports? Anybody running plugged cooler ports without trouble?

my 6.2 oil cooler ports are plugged. It runs fine with plenty of oil pressure. just remember that's a non-turbo where as your 6.5 is turbo so the oil in my 6.2 would run cooler.

I don't think any of the aftermarket turbo kits for the 6.2L included a 'manditory' oil cooler so I don't think it's a deal(or engine) breaker. I didn't abuse the thing at all either. I just drove it home and to town a couple times. Real easy, not pulling or hauling anything. I suspect that it's something else entirely. But I thought I'd see if I made a grave mistake in the judgment of the fine folks here. I had a cam bearing leave the block causing this same thing on my last pickup. Maybe it happened again.

Honestly, this might be my last 6.5. If it proves to be terminal, she's gonna get a Dmax/Alli. I wanted to put a P400 in it, but when you look at the cost compared to a wrecked LB7 truck, I just as well put the Dmax in. It won't cost any more, it'll just take more time.

Yeah, if you end up needing a whole new engine, a Duramax is certainly not a bad choice. They are not as complicated as most people believe.