Alright, I'll try to be as precise and to the point as possible. About 6 months ago after shutting of my 06 3.8L SC, I noticed a bubbling sound coming from the reservoir. When I opened it there was sludgy dark red fluid in it...NOT GOOD! At first I thought it was infamous head gasket/intake gasket issue...it wasn't. Upon further inspection and my mechanic and I brainstorming, we figured it to be the transmission cooler on the inside of the radiator had cracked and leaked into the coolant causing the problem. SO, we replaced EVERYTHING on the cooling system except the heater core. This includes: radiator, tranny cooler, water pump, plastic elbows, EVERY HOSE, and the thermostat. Replaced dexcool with the yellow stuff. ALSO, we changed the tranny filter and fluid. We flushed the entire cooling system with chemicals and filled it back up. Car ran AWESOME for 3 months, ran at great temperatures in this Arizona heat. Checked the coolant several times the first month...no loss of fluid, no discoloration. A week ago I noticed some slippage between 2nd and 3rd gear. Fluid level seemed fine, so I bought BG Transmission fluid conditioner. Checked the coolant at the same time and noticed it was low...then I noticed the sludgy film around the inside of the radiator cap...NOT AGAIN!Added some water and drove it home...shifted much better may I add. Got home and further inspected the coolant, doesn't look sludgy, still yellow and clear. WHAT IS CAUSING THIS?! All and any help will be GREATLY appreciated. Thanks guys!
