Thanks for sharing 'bout your experience with the mower.
As for this part:
how is your motor needing rings at 60-70 K, and then after replacing them, starts again at another 60 K?
The infamous AFM did it. Too much oil in the wrong places on those deactivated cylinders results in stuck oil control rings. I bought the truck at 40K miles, and it was using about 3/4 qt. in 5K miles. It increased to 1 1/4 qts in 1,900 miles.
The dealership had to go through GM's process. They fixed leaking seals, put a shroud over the oil spout in the pan, and did a "top engine soak", hoping that would break the rings free. When that didn't work, they decided that there was oil sitting on top of the valves, so they replaced the valves, heads, and 1 valve cover ('cause the PCV is built-in to it). And when
that didn't work,
then they replaced the pistons & rings. 'Twas an enormous pain in the a$$, but GM paid for it all, & gave an additional 30K mile warranty on the work. It barely used oil at all until the last 7-10K or so.
The truck has rarely seen heavy loads while I've had it, & I've used Valvoline 5W-30 All Weather with Valvoline filters. The only exception being when GM was doing the oil changes to document consumption, and after the friggin' rebuilds. They used Dexos, & A/C Filters.
I'm not happy it happened, but the dealer did all they could. Plus, with new valves, heads, pistons, & rings, it was kinda like getting most of a new motor. It hasn't exploded yet, so I feel like it'll probably hang in there for a while.
I'm just curious to see if it's worth it to give the high mileage stuff a whirl.
Thanks,
FC
