I have a 2003 Corolla S (175K miles) with a P0770 error reading for the shift solenoid. The car will shift from 1st for about 2 miles, afterwards it will get stuck in 1st; also reverse is no more, not even from a cold start. I've never changed the ATF (I know, what an idiot). 
Also, the ATF is chocolate in color and smells like a nice 2003....
So I took it to a mechanic I know to have his opinion and he tells me the whole transmission is shot. He said there were fine "shavings" in the ATF and it needs to be replaced. He also told be it won't reverse because the cloggage in the solenoid flow won't let it go backwards. So now we are talking about a $1,200 job with a used tranny.
Since the transmission shifts, it appears to me that flushing the ATF and changing the solenoids would make the most sense, but then again, I'm no mechanic.
Does anyone have any thoughts or experience with P0770 and this particular situation? I understand the fine "shavings" will be considered as a new tranny, but is there anyway to tell when too much is really too much?
Thanks in Advance!
Also, the ATF is chocolate in color and smells like a nice 2003.... So I took it to a mechanic I know to have his opinion and he tells me the whole transmission is shot. He said there were fine "shavings" in the ATF and it needs to be replaced. He also told be it won't reverse because the cloggage in the solenoid flow won't let it go backwards. So now we are talking about a $1,200 job with a used tranny.
Since the transmission shifts, it appears to me that flushing the ATF and changing the solenoids would make the most sense, but then again, I'm no mechanic.
Does anyone have any thoughts or experience with P0770 and this particular situation? I understand the fine "shavings" will be considered as a new tranny, but is there anyway to tell when too much is really too much?
Thanks in Advance!