My 03 Impala LS has been great. Excellent fuel mileage (21 avg, 28.5 hwy @ 145k miles). Using Castol Syntec, change when computer says to. Replaced catalytic converter ($800) which seems to be an Impala plague. 130k: transmission started to slip, but nothing serious. Used Seafoam Transmission and most shifting problems went away. 146k: replaced both front bearings ($650). 2.5-3 years: battery dies w/o warning.
Very roomy, HUGE trunk, very quiet touring car. Very low cost per mile to operate, very little maintenance. Super reliable.
Cabin remains hot in the back seat, regardless of air settings. Needs air vents in backseat area. Power steering fluid difficult to check/fill. Needs access tube.
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