XG300L Transmission

My gas mileage has never been great or terrible, just a bit
disappointing. I did notice, however, that the RPM's at 70 MPH are
lower than at 60 MPH. It was my understanding that the torque
converter locked up at ~35 MPH. Is there a sixth gear (overdrive)
beyond fifth and torque converter lock up. The dealer say that the
computer indicates the transmission is shifting as desired. But I
still wonder about the drop in RPM between 60 and 70. Fred

Fred, W8OY

 

That's pretty weird!. The TC can lock up as low as 35-40, but it depends on
throttle and terrain. If it does that on cruise control and reasonable
level road, take it back to the dealer and demonstrate it to him.
bill

 

http://www.hmaservice.com/webtech/iindex.asp?id=8161#_8161

 

Good research, but it doesn't cover his car. Is there an update?
bill

 

Won't do the trick. Every time I level off at 60 MPH the RPM is 2.2K.
And when I level off at 70, it's 2.05K. Absolutely repeatable at
~65MPH. Transmission tech at dealer did not address the issue except:
"I put car on computer, drove the car and computer says the
transmission is exactly right." And, of course, if a computer says it
right, no amount of experience to the contrary seems to make any
impression at all.

Fred, W8OY

 

Could also be the tach, eh? Or the ECM (or PCM) or whatever
unit passes the signal to the tach.

S25