Japmand

Can anyone verify this is normal behavior? Just noticed when I'm in "PWR" mode the transition on the 4th to 5th gear is harsh, almost clunky. It's fine once I take it out of PWR mode, but I like the throttle response in that mode, so I'm trying to see if this is normal, or if I need someone to look at the trans.

2006 GS300AWD

speedkar9

in PWR mode on my car my whole transmission acts very harsh and clunky. When coming to a stop from speed it clunks so hard to downshift and lurches the car forward. When taking off from slow stops is very jerky, even in normal mode. I've tried resetting the battery numerous times, only to have the harshness come back once it learns my driving pattern.
I think PWR mode is best enjoyed while cruising at highway speed.

Japmand

I have notice in the past that the power mode actuates the gear changes quicker with less "slide into gear", but this definitely feels wrong @ 45mph to have the vehicle be jarred that bad. I usually go into manual mode and keep it in 4th so the damn car doesn't change gears constantly at <45mph areas. The PWR mode DEFINITELY increases the electronic throttle response curve (which I like). The engineers for this transmission system were IDIOTS!

1st to 2nd @ 5MPH and 1500RPM???
5th gear + @ 40MPH??? --- Let's save gas at the expense of the transmission's lifetime (constant change of 6th, to 5th, to 4th with ANY throttle input above 40MPH).

What is the process of updating the transmission's ecu firmware? Is there any way to interface it and adjust settings for gear change timings/speed? Any devices out there to interface with the system?

speedkar9

I honestly couldn't agree with you more. This 6 speed tranny likes to upshift too much. When you slow down to a rolling stop then pickup again, its in the wrong gear, has to rev up, shift, then rev back down again before you feel the car go.
When using manual mode, the engine breaking isn't consistent either - the first few times it will engine break, but after that its as if it was free coasting again - I can't rely on that to slow me down in traffic at all!

I hate the tranny programming on these cars. But in all honestly my GS350 is slightly better than my ES330 I had previously - the lag was worse.

designo

iTrader: (6)

I drive an 8 speed GS460.
When in PWR mode, the gears hold longer. the actual shifts are the same.

Clunky noises could be from bad rear differential bushings. Don't be fooled into thinking it's a transmission issue.