ch 10

Which of the following SAE multigrade oils would likely be recommended by most highway diesel engine OEMs for year-round use in North America?

a. 5W-30

A full flow oil filter has become completely plugged. What is the likely outcome if the engine is running?

a. A bypass valve diverts the oil around the filter.

Which type of oil pump is most commonly used in current highway diesel engines?

a. External gear

Which of the following conditions could result from a high crankcase oil level?

a. Lube oil aeration b. Oil pressure gauge fluctuations c. Friction bearing damage d. All of the above

Engine oil service classifications are standardized by which of the following organizations?

b. API

Which of the following correctly identifies the source of most diesel engine oils in current use?

b. Crude petroleum

Which of the following statements would usually correctly describe the relative temperatures of the coolant and lubricant when the engine is at operating temperature?

b. Engine oil temperatures are higher than coolant temperatures.

Technician A states that the operating temperature of an engine oil should be within 58F (28C) of that of the engine coolant operating temperature. Technician B states that engine oil temperatures are probably a more accurate means of assessing actual engine operating temperature than the coolant temperature reading. Who is correct?

b. Technician B only

Which of the following is usually the preferred OEM method of testing an oil cooler bundle?

b. Vacuum test

Oil that has a milky, cloudy appearance is probably contaminated with:

b. engine coolant.

An auxiliary oil pump designed to feed oil to the lubrication circuit on a vehicle that operates at extreme working angles is known as a(n):

b. scavenging pump.

A diesel engine dash oil pressure gauge displays low and fluctuating oil pressure values when the vehicle is operated. Technician A states that this could be caused by low engine oil level. Technician B states that this could be caused by high engine oil level. Who is correct?

c. Both A and B

Technician A states that 15W-40 is the most commonly used truck engine oil viscosity. Technician B states that 15W-40 oil is not an appropriate all-season oil, because winter temperatures are often much lower than the SAE recommended ambient temperature window for this oil. Who is correct?

c. Both A and B

Technician A states that an engine equipped with EGR and DPF must use API CJ-4 or later engine oil. Technician B states that engines manufactured before MY 2017 may use API CK-4 engine oil. Who is correct?

c. Both A and B

Technician A states that an oil cooler operates by having coolant pumped through the bundle tubes and oil circulated around the tubes. Technician B states that a leaking oil cooler core must always be replaced. Who is correct?

c. Both A and B

Technician A states that the device used to signal oil pressure values to the ECM on most electronically managed engines uses a variable capacitance operating principle. Technician B states that an oil pressure sensor usually requires a V-Ref source from the engine ECM. Who is correct?

c. Both A and B

Which of the following statements best describes viscosity?

c. Resistance to flow

When interpreting a used engine oil analysis profile, which of the following conditions would be most likely to cause high silicon levels?

d. Air cleaner perforation

When investigating a low oil pressure complaint, which of the following should be performed first?

d. Check the crankcase oil level.

Which of the following API classifications indicates that the oil is formulated for diesel engines meeting MY 2017 and later emissions, and fuel economy standards?

d. FA-4