I bought my present car, an '00 Bonneville SSEi last year at about 100k miles; I switched out the ATF with some store brand Dexron VI, as I've heard good things about it versus older Dexron III (which really isn't a GM forumla any longer). Did filter too at the same time.
Since I drive the car hard fairly regularly, I thought it best to change the fluid and filter every 50k or so. Found Citgo Synthetic Dexron VI for about $5.00 per quart, so used that this time. Old fluid came out with a normal smell and appearance, no signs of overheating, but there was still a fair amount of wear metal at the bottom of the pan, and the magnet was pretty well covered.
I plan on driving this vehicle until the wheels fall off-- I suspect the 3800 Series II engine will long outlast the transmission (4T65E-HD), so with regular maintenance I hope to keep it in good shape.
With that said, how long would you run this ATF between changes? The manufacturer recommends 50k intervals for severe service only.
Since I drive the car hard fairly regularly, I thought it best to change the fluid and filter every 50k or so. Found Citgo Synthetic Dexron VI for about $5.00 per quart, so used that this time. Old fluid came out with a normal smell and appearance, no signs of overheating, but there was still a fair amount of wear metal at the bottom of the pan, and the magnet was pretty well covered.
I plan on driving this vehicle until the wheels fall off-- I suspect the 3800 Series II engine will long outlast the transmission (4T65E-HD), so with regular maintenance I hope to keep it in good shape.
With that said, how long would you run this ATF between changes? The manufacturer recommends 50k intervals for severe service only.