Tried to search before I registered. No luck so far. 2006 gs300 awd. Car is having weird trans issue. Car runs and drives good. But when steering wheel turned, it just free Rev like it's in neutral. This is not just happening while driving. Did a test while parked also. Car is stationary, in drive. Steering wheel turned even just slightly. Give it gas. Free Rev as if it's neutral even though in drive. Straighten the wheel as if I'm going straight and give it gas. Cars perfectly normal accelerating and moving. No slipping or nothing out of the ordinary while Car is moving. Anyone ever seen this problem. Checked fluid in the trans and it's not low nor is it dirty. Thanks.

 

Trans brake!

 

I wonder if you have a differential or cv axle issue. Is there any clicking from the cv axles when you turn?

I would take it to a mechanic and let him diagnose it before you dump money on repair that you dont need.

 

did u ever determine what it was? I just installed. a new front differential. but I think I need to order soldernoids too. When my car is in park. it's not actually in park and rolls. pleased help so I do t hav​​​​​​e to buy a new trans!

 

It’s the ECU, common problem on gs300. Needs the be rebuilt.

 

https://siaelec.com

these guys will fix you up.

 

https://siaelec.com

these guys will fix you up.

 

It's probably your Transmission Control Module located in your ECU. I started a thread last week after reviewing similar issues on this site . I'm having a hard 2-1 downshift when stopping. I'm sending the ECU to SIA wh/ is an electric shop in IL. https://siaelec.com/
I went on Ebay & purchased their Lexus ECU Repair ECM- PCM Engine Computer Repair & Return for $115.oo. I called them & they quoted me $195 for the same thing. All their reviews are solid on Ebay. I saw their reviews on Google after the purchase on Ebay. Reviews on Google are ****ty for the past 6 mths. Hope this helps.
https://www.ebay.com/itm/22397143747...&segname=11051