Koreatown

Hello, I am having a problem where my car wont shift past 4th gear. If I stomp on the gas pedal and it hits red line then it shifts. I'm going 4k rpm at 80mph. Is this a transmission issue or a solenoid?

ServerTech

Need more info:
How many miles on this gem?
Is transmission fluid black and has a burnt smell?
How many miles since trans fluid was changed, if ever?

Koreatown

Hello has 155,000 miles did an transmission change 2k miles ago it was pretty black. Transmission light is on I lost the service paper they gave me some p2757 something like that error code. I think it might have to do with the solenoid. But went to a mechanic and said I need a new transmission. Your thoughts? How can the car shift only if I red line it on 4th gear but when I manual shift it, it won’t shift. The gear shift are pretty smooth first to second year maybe a little jerky at times

ibidu1

iTrader: (1)

Remove your ecu, mail it to this company

https://www.ebay.com/itm/Lexus-GS300...YAAOSwu4haz235

2006 year is the only year to have this issues where the transmission ecu, thats built inside the regular ecu goes bad. This company specializes in these repairs. Its pretty common! Try this, and if it doesnt work out for you then swap out a solenoid, which is common aswell.

Koreatown

How much damage am I doing to my car driving on the highway using only 4th gear. 80mph 4,000 rpm?

ibidu1

iTrader: (1)

Not wise at all, the longer you leave it as it is you open a door of maybe destroying the transmission. Park the car, remove the ecu, mail it off. Rent a cheapy car if you have too for a few days. From what I understand those guys are quick at repairing the ecu's.

FLYIN4D

That sucks *****! Ugh

Ae86rob

Sim issues here brother mines acting up I bought the car with a blown motor an the lady didnt say any thing to about. Replaced the motor an surprise tranny issues! Issue is infamous solenoid codes p0761,p0766,p2714 I've replaced s3 s4 with new solenoid with no luck! If I shift in sport I get 1st 2nd 3rd 4th no 5th gear 6th for 2 seconds an kicks back dow to 4th! In D I get 1st 2nd 3rd touches 4th gear kicks back into 3rd goes into limp mode an wont shift past 3rd unless I turn off the car an clear codes! Fluid was black as coffee I've changed it 5 times now replaced s3 an s4 solenoids for p0766 p0761 but I still get the same codes an a new code p2714 now I'm gonna send my ECU out an see if it fixes the problem an I'll update you an see if it works for me! Let me know if it helps you

Koreatown

Please update me!! 100% same problem as me

Ae86rob

Are you gonna ship out your ecu lol I'm doing mines tomorrow! Another option is Lsx swap,2j swap, or manual trans swap lol but this has to stop! Anyone wanna buy a few gallons of used tran oil lol an new solenoids

Koreatown

prob next week. How long does it take for them to finish and deliver?

Koreatown

any updates?

ls430w140

I suggest looking at Engine Coolant Temperature sensor first.

lextout

do the 2006 300’s share the same transmission with the 06 gs430?

JHanrahan

I belive I need to send in my ECU for repair. Have new exhaust, cats and 02 sensors, but getting 02 sensor code. Only one time several months ago I had trouble shifting...stayed in 1st and wouldn't shift. Turned car off and restarted...no problem since. Car also wont recognize key once or twice a month...only happens for a couple seconds then it will recognize. Battery is new, so its not batter. Dealer says computer is going bad. My question is this the ECU inside the hood on the drivers side by the fuse box? Want to make sure I take out the right thing? Photos of ecu location would help. Thanks in advance.