The engine in the Yukon is rattling now, seemingly on every start up and not just after sitting overnight or a few days. Pressure is slow to build. Oil pressure in gear at a traffic light can drop to 18 psi now. The o-ring has never been replaced. The motor is just shy of 217K miles.
Just completed the 12th tire rotation for these Michelin Defenders. They are 49 months old and have 52K miles on them now. Tread depth is 6/32 on the inside and outside and 7/32 in the middle on all four. It was this way last time and we bumped the air pressure from 30 to 31 psi. Looks like another 2 psi are needed to wear them even again. What say you?
Just completed the 8th tire rotation on the Defenders on the 2013 Sierra. They have 33K miles on them now. They are at the same tread depth now as the Yukon's Defenders were at the same mileage. These tires have a tread depth of 8/32 on the outside and middle and 9/32 on the inside. This kind of wear did not exist at the last tire rotation. This indicates too much of a positive camber and we want -.1 degree. Hopefully, my alignment guy, who I last saw almost 4 years ago, hasn't retired yet! This truck calls for 35 psi all around and that's what we've been running on her.
That 6.2 is so much fun to listen to and drive!
The Yukon XL is shod with: Michelin Defender LTX M/S - P265/70R17 SL 115T (62115 or 19340389)
The Sierra is shod with: Michelin Defender LTX M/S - P265/65R18 SL 114T (56465 or 19357580)
These standard load tires have been replaced with extra load or XL tires.
The Yukon XL ran KO2s in load range C shortly after I bought and they lasted 4 1/2 years and just over 50K miles. I made a spreadsheet to compare the mileage between those tires and the Defenders and the data was surprising. The Defenders have gone to most of the places we drove through with the KO2s and never got stuck. The truck coasts for a long time on the Defenders whereas letting off the gas with the KO2s was like deploying the speed brakes or a parachute to slow down. The KO2s picked up road hazards all the time and 3 of the 4 were patched. Defenders are road hazard free. The Sierra had KO2s as well (Load Range E) and the first road hazard to ********* the tread destroyed the tire. Defenders quickly took their place. She got her speed and horsepower back after that. She turns 14s in the 1/4 mile and is bone stock.
What do you think of this chart?
Let me explain the center section to you. The EPA considers 100% city driving to be an average speed of 21.2 mph and 100% highway driving to be an average speed of 48.3 mph. The city and highway averages pulled their data from those 225 fill ups in their respective categories. The Gallons Per Hour averages came from all of the fill ups with those tires on that kind of fuel and it is to be noted that the KO2s were driven at an average speed 4 miles an hour slower than the Defenders which is why the defenders show a higher fuel consumption per hour (29.5 mph vs 33.5 mph).
This does not include the change to 3.73 gears. That's a different spreadsheet!
Hope y'all have a great week!
