Looking for help... 226k 2005 AT. Been noticing a faint high whine that is apparent at all speeds. Car also has not maintained perfect speed -almost feels like it's hitting a headwind now and then (but isn't). Today, while driving about 30 mph, rpm dropped like it was in neutral and green light next to gear indicator turned off. Only lasted a second and then went back to normal. Thoughts?

 

Check your ATF fluid level and condition with engine hot and switched off. Assuming you've been religiously changing the ATF every 30k it should have a red tinge and not smell burnt. The BDGA transmissions are known to eventually burn out the 3rd/4th clutch packs with mileage. Replacing the 3rd/4th pressure switch can allegedly buy you more time, theres plenty of forums about this.

One thing I hope you've done is change out the the ATF-warmer filter on top of the transmission case. I noticed several high mileage TLs in junkyards that had the hardened glue from the filter break apart and restrict flow in the banjo bolt. Take a look into inspecting that as these trannies are sensitive to hydraulic pressure.