Hi. I have gs430 2006
a few days ago I noticed that during slow down from 3rd to 2nd there is jerk and from 2nd to 1st the jerk became very hard
i check camputers evrey things good I also change the flued and filter but still the problem exists

any suggustion ?

 

Some of the solenoids fail on those 6 speed transmissions. I had an IS250 at work the other day that would pretty much lock the wheels on downshift from 2nd to 1st.
One of the solenoids was a shift solenoid and the other was the lock up solenoid. Speak to an auto trans shop, they should be able to sort it out.

 

I already check the valve body its fine and the problem still exist��

 

Ever figure out the problem??

 

i have a 2006 lexus gs300 with the same issue with 208,000 miles on the odometer after searching around, it may be related to the ecu. Any updates on your vehicle?

 

My 2006 GS300 had the exact same symptoms. I ended up finding the root-cause within the ECM and was able to fix it by repairing various solder-joints on various SMD components. Here's a full write-up with details in case anyone else is experiencing the same issue: https://www.clublexus.com/forums/gs-...ft-solved.html