Im not sure if this has been already talked about but, have you noticed that your transmission slips all the time. and sometimes when slowing down the rpm jumps a little. Its really getting to me, i have an appointment for this to get checked out im just unsure if it just mine or is it a common thing?

 

I haven't really experienced this on mine but my mom does have a similar problem on her '04 RX... there's a reason Motor Trend referred to that transmission as "Mayonnaise" She's been to the dealer a few times for it but they've had no fix for her.

 

It sucks and the dealer says there's nothing wrong.Welcome to my world.

 

Yeah I have the same problem. When slowing down, you can feel it shift into lower gears. I guess that's just how it is

 

i have notice the same on the IS 350 and mine is an 07 with on 5k miles on it? i do drive it hard but it should hold up. please let me know what they say!

 

It's called downshifting.

 

x2...i was waiting for someone to say that. if it is downshifting really hard that should not be normal, but i doubt there is a problem.

 

I notice this Alot on my Father's 05 Rx330. I have begin to notice it as well on my IS250, However it isnt as bad. Hope there is nothing wrong with the tranny, might be lexus thing?

 

I think what some people are feeling, or seeing if they are watching the tach, is the torque converter clutch(tcc) engaging and disengaging. The tcc will lock the engine and transmission torgether so there is no slippage going on in the torque converter(which is normal) they do this for improved fuel mileage, now it is not favorable to have the tcc engaged all the time and during these times you may feel the tcc disengage. Try this, drive down the road and maintain a very steady speed of about 50 mph, now without taking your foot off the gas just ever so slightly touch the brake pedal but not hard enough to actually start braking the car, if you are watching your tach when you do this you should see the rpms go up a couple of hundred, this is the tcc disengaging in anticipation of the car slowing down and is completely normal.

 

if your tcc is disengaging in your try this scenario, why would the rpm go up?

doesn't make sense in that scenario because since you are holding the accelerator(light constant load such as cruise control) and then adding resistance with the brakes, you are just creating heavier load (like going up a hill with cruise control). when u use cruise control to go 50 mph and then u approach a hill, it's going to fight its way up the hill harder to go the same 50 mph so obviously the rpm is gonna go up a few. when you go down a hill, the engine doesn't have to work so hard so it'll go down a few rpm.

 

When the tcc disengages it is actually unloading the engine and therefore the rpms increase, in this scenario we are only pushing the brake pedal hard enough to send a signal to the pcm telling it that we are braking...we are not actually applying the brakes. Also you can't try this using cruise control because as soon as you touch the brake pedal the cruise control disengages..obviously.

 

For the guys that are experiencing the hard downshifting, is your ECT button on normal or power. When in power mode, it really changes the feel of the trans. When in normal, the shifting is smoother.

 

You are correct. I just bought my IS 250 3 weeks ago, and have to commute to downtown Houston with it everyday. My commute involves navigating through a parking lot because traffic moves at 15 mph all the way in to downtown. I had my car in ECT power mode because it allows for faster acceleration. However, I noticed that the car felt funny on the downshift, and I could tell that the speed at which my car would come to a stop was bothering the other commuters behind me. One nearly collided into me.

I then switched off ECT power, and the downshift and commute is much smoother. I still use ECT power, but not in stop/go traffic.

 

Ummmm....its part of the transmission it helps you out by engine braking (like the big riggs, Jake Brake) when you drop speeds fast the tranny jumps to lower gear, rpm's increases and slows the car...really come in handy on a down hill...I had the same thing on my RSX.

 

I'm abit confuse as to the meaning of slipping in this discussion.

Coming from a Honda owner and with the Prelude and it's notorious auto tranny problems. Gear slipping is when the gears is having trouble engaging during upshift or downshift, normally with a "grrrrrrr" sound. Now my Prelude had the gear slippage symptoms, and i was told it was actually so by a reputable Honda Only mechanic, when i sold it but the new owner which i happened to know, didn't do anything to it and she said it's still working with no problems. I'm not sure what she did if anything except changed the tranny fluid.....

So back to this discussion, what i read from the initial poster is not gear slipping problem/ auto tranny issue, but the auto tranny at work as it should. Believe me if there is a problem with the auto tranny i'd know it.