300BomDia

Hi,

I recently got a 1999 RX300 with 230.000 on it. It runs like a dream, perfect condition. The person I bought it from drove about 45 miles on the highway to work each day. When I got the car a few weeks ago, I guess I didn't realize whether or not the O/D was on. So, today while just browsing the user manual, I see that if the O/D is OFF, it will show on the instrument cluster. I have been driving with OD on. Now, I live in the middle of nowhere, so most of my driving is stop and go until I get to the "big city". So, once I realize I have been driving in the wrong, I flip the OD off. However, when doing so, I realized it was at about 3,000 RPMs going about 55-60. It just didn't want to shift out.So, I flip the OD button, and it drops down to normal.


What do I do?! Keep driving with the O/D on, or just keep it off unless I'm doing highway driving? Is it okay to swith the O/D while driving?

I should mention, I live in Minnesota, so it's been very cold. The car starts, shifts, drives perfectly. I let it run about 10-20 minutes before driving anywhere too.
Thank you!

JAB

I'm not sure I understand your concern. On my 1999 RX, I seldom operate that button; no reason to. Just leave the OD engaged, and let the automatic transmission control unit worry about (1) whether the engine has reached proper operating temperature and (2) whether ground speed is high enough. By playing with the button - causing the instrument cluster light to read 'O/D Off' - you are keeping the engine at an unnecessarily high RPM, which wastes fuel.

99rx

iTrader: (6)

Yeah, by leaving the o/d off your keeping higher rpm's and wasting fuel. And with suh high mileage I would mess with the transmission all that much. And yes it fine to turn it on and off while driving. Really all o/d is for is going up a big hill, turn off, towing a trailor, turn it off, normal driving, stays on.

salimshah

Leave the O/D on.

If you feel that the transmission is hunting between OD (on/off) on its own then you take it out of its misery and switch the OD off. The hunting usually happens when you have loaded the RX (specially with a trailer) or going over a hilly patch (again with enough laden weight, that the transmission is searching for the right gear).

Warming for 20 min is excessive. I would suggest warm up of a minute and then drive gently till the optimum temp is reached. When you let the engine idle for long the only thing you are warming up is the engine block and the interior. The transmission does not warm up.

Salim

Raoul

You are overthinking this.
All automobile manufacturers know you do not want a bunch of lights glowing at you from you dash.
So....
O/D on = Light Off (this is normal)
O/D off = Light On (you are now being reminded that your O/D is off and will continue to be reminded until you come to your senses)

I have had my F-150 for 11 years.
I turned the O/D off one time, I was towing a boat thru the mountains of WV.