Dunno that it was a "test", per se. I thought it was their hope-beyond-hope-that-this-works-to-unstick-the-stuck-rings attempt. As you can see below, it seemed to do precisely nothing for the problem in my engine.
Here's the chronology:
63,179 Start Oil Consumption Test (OCT). Installed AFM deflector, and cleaned carbon from cylinder [by pouring in GM Top Engine Cleaner through the plug holes] as per bulletin 10-06-01-008B. Replaced leaking rear main seal (12639249, 89060436). Replaced leaking left front axle seal (15801507). Replaced leaking transmission pump seal (24245110, 8654799, 24202535, 24226315, 12337931, 10x24233361, 24205103, 3x15709703). Note: all under warranty.
63,179 Dead spot in steering. Steering gear had not been tightened after previous repair. fixed.
64,340 1/2 qt. low. Topped-off, & advised to return.
65,532 1/2 qt. low. Topped-off.
66,766 1/2 qt. low. Stated that 1.5 qts. in 3,587 mi. is within their consumption spec of 2 qts. per 2,000 mi. Oil & filter change.
68,744 1/2 qt. low. Topped off. Reiterated this was, "well within" the spec.
70,093 1/4 qt. low. "Well within" the spec. "THIS COCLUDES (sic) THE OIL CONSUMPTION TEST"
71, 708 1 qt. low. "Reschedule customer to complete repairs". Oil & filter change. Sending paperwork to GM to get a SmartCare plan.
73,328 "removed cylinder heads and found excessive oil resting on top of valves. Checked valve stem wear and had excessive valve guid (sic) wear allowing oil to burn off in cylinders. Head. Cylinder - replace. Both Banks". Heads, valves, bolts, gaskets, seals, etc. Oil & Filter change.
75,228 "CUSTOMER STATES SINCE LAST REPAIR, THERE IS STILL A CONSUMPTION ISSUE. INSPECTED AND FOUND OIL CONSUMPTION AT 1 1/4 QUART IN 1900 MILES. CUSTOMER WILL RESCHEDULE FOR REPAIR"
75,530 "Followed bulletin 10-06-01-008B as per TAC instructions. Completed 2nd half of bulletin. Replaced pistons & rings as per bulletin. Tested and set oil to correct level. Request customer to return in 1,000 miles and re-evaluate consumption." Pistons, ring kit, gaskets, seals, bolts, etc., 2 spark plugs, oil & filter change, etc.
No more oil consumption.
76,929 GM Smart Care plan issued, extending warranty on listed engine components to 106, 929 miles.
Now at 116K+, and it will use maybe 1/4 qt. per 5,000 miles.
FC
Dunno that it was a "test", per se. I thought it was their hope-beyond-hope-that-this-works-to-unstick-the-stuck-rings attempt. As you can see below, it seemed to do precisely nothing for the problem in my engine.
Here's the chronology:
63,179 Start Oil Consumption Test (OCT). Installed AFM deflector, and cleaned carbon from cylinder [by pouring in GM Top Engine Cleaner through the plug holes] as per bulletin 10-06-01-008B. Replaced leaking rear main seal (12639249, 89060436). Replaced leaking left front axle seal (15801507). Replaced leaking transmission pump seal (24245110, 8654799, 24202535, 24226315, 12337931, 10x24233361, 24205103, 3x15709703). Note: all under warranty.
63,179 Dead spot in steering. Steering gear had not been tightened after previous repair. fixed.
64,340 1/2 qt. low. Topped-off, & advised to return.
65,532 1/2 qt. low. Topped-off.
66,766 1/2 qt. low. Stated that 1.5 qts. in 3,587 mi. is within their consumption spec of 2 qts. per 2,000 mi. Oil & filter change.
68,744 1/2 qt. low. Topped off. Reiterated this was, "well within" the spec.
70,093 1/4 qt. low. "Well within" the spec. "THIS COCLUDES (sic) THE OIL CONSUMPTION TEST"
71, 708 1 qt. low. "Reschedule customer to complete repairs". Oil & filter change. Sending paperwork to GM to get a SmartCare plan.
73,328 "removed cylinder heads and found excessive oil resting on top of valves. Checked valve stem wear and had excessive valve guid (sic) wear allowing oil to burn off in cylinders. Head. Cylinder - replace. Both Banks". Heads, valves, bolts, gaskets, seals, etc. Oil & Filter change.
75,228 "CUSTOMER STATES SINCE LAST REPAIR, THERE IS STILL A CONSUMPTION ISSUE. INSPECTED AND FOUND OIL CONSUMPTION AT 1 1/4 QUART IN 1900 MILES. CUSTOMER WILL RESCHEDULE FOR REPAIR"
75,530 "Followed bulletin 10-06-01-008B as per TAC instructions. Completed 2nd half of bulletin. Replaced pistons & rings as per bulletin. Tested and set oil to correct level. Request customer to return in 1,000 miles and re-evaluate consumption." Pistons, ring kit, gaskets, seals, bolts, etc., 2 spark plugs, oil & filter change, etc.
No more oil consumption.
76,929 GM Smart Care plan issued, extending warranty on listed engine components to 106, 929 miles.
Now at 116K+, and it will use maybe 1/4 qt. per 5,000 miles.
FC