Fairly religious about oil changes. Castrol GTX 5W30 x 4.5 quarts every 7,000 miles (LOTS of highway driving). At about the 4,000 to 5,000 mile point, I check my dipstick and the oil on it always has a reddish hue to it. I'm actually panicking because I've had my oil pan replaced a year plus back, and it's been doing this ever since! Is there any way I check to see if I'm bleeding transmission fluid into my engine now? It's a pain because GM decided to omit the very necessary AT dipstick on these models. Aside from draining my tranny out and measuring the actual fluid contained therein, how can I troubleshoot this? My 2004 Cavalier sedan is my only ride, so I certainly can't afford to futz things up on my day off and be stranded away from work!

The only way you could have tranny fluid in your engine is if there was a leak by the torque converter, AND your rear main seal was leaking. But the odds of this happening are slim to none. You would have noticed an engine oil leak and tranny leak.

I thought the rule about changing your oil was every 3 000 miles or 3 months, whatever comes first. And have you tried changing brands of oil to see if this fixes the colour.

I haven't taken the change the brand approach because I'm actually terrified of all the crappy urban legends I've heard regarding them (e.g. Pennzoil = sludge). Any recommendations on what brand and mix (Conventional/blend/full synthetic) to use to my benefit? I'm still fairly well stock (K&N 57 series FPK intake kit), and since it's a long drive to work, I've been conserving gasoline and not hot-rodding the motor lately. I just found out this evening from the company that a transfer is in place for starting 28 July 2008, so that means I'll be 15 minutes away from work (Less than the hour it takes for now!), so I can definitely adjust style soon.