I have a v8 ford 250 power stroke, 2005. I tow a 4000 lb trailer. It worked fine until about 35,000 mile. After that, when climbing and towing the trailer, the turbine pressure would drop from 30 to 10 or 20 lb and the rig would drop from 60 mph to between 40 to 50 mph. The turbine and the EGR have been replaced, as well as EGR cooler (had carbon deposits). But still the same problem prevails, turbine loses pressure and the speed drop. This did not happen until the mileage was over 35,000 miles. Has been at the Ford dealer 5 times. Any suggestions please?

Pedro

It may be a wastegate-related problem. The most common reason is that all of the compressed charge air is not getting to the engine. It's leaking somewhere, causing a fuel-rich condition. Check the hose between the intercooler and the intake manifold. Also, check the hose between the turbo and the intercooler.

The wastegate's normal job is to keep boost pressure from becoming excessive. However, the following can happen:

. Valve can stick open--there may be a boost control solenoid.

. Seal for the valve can crack.

. Spring can break.

. Turbos can fail. It may not be spinning. Turbo failure is much greater on trucks that don't use full-synthetic diesel HDEO.

. Wastegate is not receiving the correct pulsed pressure from the computer.