2009 GMC Acadia, left front tire always low even with regular rotation at oil change. When I fill it or they fill it after rotation, it loses several pounds relatively quickly; the other three tires maintain correct pressure, lose a pound or 2 over time but certainly normal.
I purchased used in october (76k mi). Car has had 3 rotations. It does have tire pressure monitoring. Tires in good shape, so far as I can tell the rims are in good shape. Even if something was up with rim or valve stem, I’d think the issue would have stayed with that tire as it was rotated around the car. Any advice?
Unrelated but just for full info, in solving a surging / stammering loss of power at highway speed on incline (turned out to be 2 coils), my warranty covered replacement of 2 valves, 2 coils, full transmission replace (with fluids, alignment etc – the coils code wasnt popping up yet so lucky me), cv joint (spotted slung grease when looking for other issues). The larger Replacements and fixes have been much more recent, this pressure problem predates them and has persisted despite all rotations and alignment.