rlchv70

Check the turbo drains. The HP turbo drain is a tube with o-rings. The tube can get bent during turbo install, causing a leak. The o-rings could have failed as well. The LP turbo drain is basically a tube incased in rubber. These are less sensitive to failure, but anything's possible. The oil cooler cover is a possibility, but not likely. It would have to fail the interval o-ring, fill the cavity in the block, overflowing and leaking. The turbo oil supply line or the oil sensors could be leaking on top of the cooler cover. It could also be the base of the oil filter housing.

Did you check to see if the water pump shaft is connected to the impellar? I've seen impellars spin on the shaft.

120-150 miles is within the "normal" range, but on the low side.

Have you inspected the turbo and charge air cooler (intercooler)? Remove the HP compressor cover. Look for excessive coking. Some coking is normal and expected. However, highly loaded engines will coke much faster. This coking decreases the turbo efficiency. Decreased turbo efficiency leads to more soot production, leading to more regens. Similarly, if the CAC is plugged, it will lead to more soot production and more regens. Anything that decreases airflow will lead to higher soot output - clogged air filter, restricted exhaust, etc. Another possible factor would be a stuck open EGR valve, but that should throw a code. The 2.5 psi restriction may not sound like a lot, but it depends on the running condition. The ECU uses a complex calculation to estimate the amount of soot acumulated in the filter based on the MAF flow and the backpressure. That gives me another idea. There may be an issue with the MAF sensor. If it is inaccurate due to build up or an air leak downstream, it could lead to more frequent regens. Hope this helps.

Checking the return lines at the heads may help you isolate a bank, but it is really subjective. An easy way to disable fuel injection is to disconnect the fuel rail sensor. This will set a code, but the injectors wouldn't fire. The best way would be to crank the engine over a few times and then bore scope the cylinders through the glow plug holes to look for any fuel in the cylinders. You might be able to just remove the glow plugs and watch for fuel squirting out. Alternatively, you could remove the exhaust manifolds and watch for fuel coming out of the ports, but this is a PIA.

Is this the guy? http://www.thedieselstop.com/forums/f35/help-per-ford-20k-new-engine-improper-maint-207753/

Some cavitation is expected on these engines. Typically, it doesn't cause a problem.

I'd bet an EGR cooler failure.

If you see black smoke, then the DPF is bad.

You're right. I was using International's 350 hour interval, it's higher due to the larger pan. But, I would suspect that something else is going on here. I'm willing to bet that it's not soot thickening the oil, but dirt. Did you get the sample analyzed? Were there any obvious oil leaks? These could suck in dirt under some operating conditions. Any gaps downstream of the air filter?

3-4 oil changes would be okay. Regarding what oil to use: Follow the owner's manual! CJ-4 is needed for the DPF. 15w40 is needed during the summer. 10w30 would be too thin with the higher temps, especially with fuel dilution from DPF regens. 10w30 isn't even really needed unless it gets really cold.

Well, this won't be the "official" reason, but I think it makes sense. After running the engine, the radiator will suck in air from the degas bottle as it cools. Also, with the t-stat closed, pressure in the degas may be higher than the radiator, pushing air in as well. The next time the engine is started, this air doesn't get pushed out of the radiator right away. As the radiator starts heats up, the air allows for hot spots in the radiator. These hot spots cause extra stress. Alternatively, there may be a water hammer effect. You know how when you shut off a faucet, you'll sometimes here the pipes vibrate? It's because of air trapped in the system. The air acts as a spring causing pressure waves. With the new venturi tee, when cooling down or with the t-stat closed, the EGR cooler is definitely at a higher pressure than the radiator. Coolant will back flow into the radiator, preventing the air pocket from forming.

Yes, it is possible to get a passive regeneration on some systems. Others don't work as well, and the Ford system may be one of them.

Higher load may not lead to fewer regens. Higher load means more soot production. You may actually increase your regen frequency.

I would think so.

Some thoughts: Charge air cooler (intercooler)? When were the DOC and DPF replaced? It's possible they could have clogged again. You say that the regens are every 60 to 70 miles. Is this unloaded? Highway or city? Also, I assume that you reflashed it back to stock to ensure programmer was removed.

Just a few things to look at: Supply pressure to the HP pump - Is it good under all conditions? Any internal fuel leaks? Have you inspected the fuel rails for blocked passages? Hope this helps.

Take a fuel sample. I'd bet he's not using ULS fuel. Also, if there is black smoke from the exhaust, he has a cracked DPF.

I wouldn't do this. Distorting the bellows on the vertical cooler will likely lead to failure.