flattire

Hello, I have a 2006 lexus is250 that is an automatic. I have had it for about a year now and just wondering if there is a way to tweak my transmission. For example im in sport mode driving in 5th gear going about 45mph, and i put my foot to the floor it automaticly downshifts for me rather than just staying in the 5th gear. Is there any way to change this so it wont downshift for me? I know the transmission just like a gear limiter but is there anyway to fix this?

vapid2323

I expect that to do this it would involve reprogramming the ECU and currently that is not something many have been able to do.

Gville350

iTrader: (10)

Try switching it into "Snow" mode while on the HWY to see if it gives the results you're looking for.

flattire

This didn't change anything just less throttle response..

jgbackes

iTrader: (2)

I'm not sure what you are hoping will happen. Do you actually not want it to downshift? When you step on the gas you are telling the ECU "Move It!" The best way to do that is apply more fuel and down shift out of overdrive into 4th gear.

Seems to me like it's working as designed. What am I missing?

IS350AWD

This is versus a manual; if you're in 5th gear, it stays in 5th gear when you accelerate. Since the automatic is a gear limiter and not a gear selector, it is not possible in this vehicle (expect I believe the IS-F).

flattire

I really wish i could change it but i guess there is nothing you really can do

shawnxjeon

I don't quite understand why you want to accelerate but don't like the downshift either =P

and the "Sport mode" makes the shifting point different so.. I am not sure I quite understand

SH4DY

I'm with you flattire. There are many times when I would like my 350 to stay in gear instead of down-shifting. These cars have plenty of grunt down low. More times than not it doesn't need to downshift, the extra throttle input alone would suffice.
I think the only way it won't down shift is if you are in sport and start in 1st from a stop or slow roll and then shift up as you accelerate (or not because it will shift for you at redline).

The paddles are almost like false-advertising: no rev-matching on down shifts, taking forever to upshift, shifting for you at redline. What's obnoxious is seeing the new Camry (or Corolla?) commercials showing off what look like proper functioning paddles.

I actually emailed Lexus about this about a week ago and have yet to get a response...
Edit: Got a reply from Lexus today from a real person (unless the robots have names...) apologizing for concerns about their DIY offerings. *sigh*

flattire

The DIY offerings? lol thats pretty lame... Im going to ask a mechanic the next time im down at lexus and see if this can be changed with a computer setting, its worth a shot! Haha

cdown007

So my understanding is you want your transmission to work harder in 5th gear and acclerate faster while staying in 5th gear??? I am confused by that, why would you want to do that?

Sports mode allows you stay in a lowest gear possible with a high rev range without damaging your enigne, so when you put your brake on or go slower, it adjust and automatically decreases the gears also when you step on the gas it dosen't want to stay in 5th gear it will drop to 4th and 3rd gear allowing higher RPM. Were normal mode just says I am gonna be lazy and stay in 5th gear while your doing 20mph and as long as you don't put the gas down I wont go any lower, slower rotations which is good for MPG, but hurts the accleration.

If you want that type of reaction either stay in Normal mode and use the manual shifter or paddles, it allows you stay normal but you can maniuplate some of the sport mode idea by doing your owning shifting, which sport mode is doing it for you.. just being really annoying at it.
Also a side note, snow mode really just allows you to start out in either 2nd or 3rd gear to allow a SLOWER rotation so you won't spin out when at a stop on snow or ice.

Sorry if this confused you, I had a better write up but my comp froze and it erased what I wrote.. so this is a quicker version.