So true. I think when they tell u around 100k to change fluid, u should change it around 60 or 70k.

 

my 09' GS has just over 75k....and as soon as the weather warms up a bit, I'm chaining out the tranny fluid. I replaced the rear diff fluid a few hundred miles ago and have everything needed for the tranny...just need it warm up some first. Scary to hear about so many tranny issues with these at relatively low miles. I keep and drive cars for a LONG time (Honda's) and have never run into tranny issues until the 200k mile mark or higher.

 

Hondas are notorious foe bad trannies.

 

well...I've got a 2003 V6 EX Accord that I still use as a daily work driver and it's right at 300k miles. Now, I did replace the tranny at 258K miles...but I'm totally fine with getting "only" 258k out of a factory tranny. Seems from reading this forum that many are experiencing tranny issues with less that HALF of that kind of mileage on these GS's which are twice the money.

Put 190k on my wife's first Honda Odyessy before any issues with the tranny. Had 140k on the next Honda Oddy before it was totaled..again, no tranny issues. Her current Honda Oddy has 133k ...and again, no issues whatsoever.

Early and mid 2000's Honda V6 tranny's had issues when not serviced frequently. Honda/Acura came out with an updated service bulletin and recommended doing a drain & fill 4 times, about every 60k I believe. I would do that process and then simply do a drop and fill every other oil change (@10k mi) and called it good. From reading this forum's "DIY tranny service" thread...it seems many are suggesting doing the same "drain & fill" multiple times to remove the old fluid on these 3rd gen GS's. I'll be doing that shortly to HOPEFULLY give my GS tranny more life. I'll be very disappointed if this thing can't do 200k miles on an original tranny.

 

Well at least you had a check engine light that was on to figure out the issue.
On mine, there are no light on and is doing this. Yours was an easy fix because the light was on.
It's a mystery on mine. I just replaced the trans with a low miles one and still doing the same shxT!

 

Have you serviced the front and rear differentials? Check all your engine mounts. If that doesn't fix it then I would start checking the wire harness...the ECM is probably the last thing I would replace...

 

Front and rear differential? Do u mean the front and rear driveshaft that's on the diff to the trans?
This is a mystery. Tomorrow, I'm going to place a go pro camera and record it and see from there.

 

I did another test run on the freeway? I was going about 80 or so. When I floored it and the trans did not downshift right away. There was some hesitation and when it downshifted, the car jerked/clunked underneath. This doesn't happen on lower speed when I for it. This kinda makes me think it might be ecu related or sensor, but not sure because there is no codes. This shxT is got me going crazy! I would rather the car throw some codes, so I know what to fix.
Man, this sucks big time!! This is my 9th or so lexus that I have owned. Now because of all this, makes me not want to buy a lexus anymore.

 

Did you guys read post #24?

Could also be your engine missing through some chevron fuel injector cleaner (techtron) in your tank.

Could be bad diferential bushings, tranny mount, motor mounts. Could be lots of things. Bad coil spark plugs. You got to systematically eliminate probable causes

 

My car doesn't have a check engine light on like the guy on #24.
If it was, my car probably would be fixed by now.

 

I checked online today and saw some transmission downshift issues from a bmw forum.
The issues seems very similar of what we are having. They were able to fix the issues with a reprogramming of the tcm(transmission control module). This makes me wonder if I need to replace the ecu on my gs430.

 

mine 08 GS 88K with the same issue.
I found this when it was around 60K. I checked with the dealership.
They said it's normal and don't need to worry.

 

you up and replaced the whole tranny first?! that had to be a decent chunk of $$$$ even if you provided the labor. I would've thought that there would've been a few cheaper things to try first, no? So even with a totally different tranny...you have the exact same issues? Damn. That's a tough one to swallow. Sorry to hear this. Be curious to see what it finally turns out to be.

 

Not sure if i have a similar problem... when im going pretty slow when its cold it does this around 10-25 mph... its like im pressing lightly and trying pushing slowly... its at around 1000rpm and then jumps to 1500-2000rpm as if it just dropped a gear and then just decides to go back to around 1200-1500rpm since i already picked up the speed... its as if this is a baby! i wanna fix this problem too hopefully its not a tranny problem... i dont think we've ever flushed the tranny or diff and at 80k miles.... I think my brother said they changed the fluids at around 60-70k miles but u know some mechies... they do half of the job and say its been done!

 

I finally got a code yesterday. The code was p0756(solenoid b). Kinda got excited to get a code,lol!
So I ended up taking the solenoid from my old and installed to the new. The problems are still there.
WTF!!! Now, I have to see if it's ecu related or wire harness. I'm thinking ecu, so I'm looking around for one. I'm getting really fed up with this car. Don't think I want to get a gs again. This is big time bullshxt!! My second gen is a lot more reliable. My second gen has a lot more mileage(165k) never had any weird electrical issues. You would think a newer gs would be more reliable, but this is totally
Bull!!!