https://drive.google.com/file/d/1EDUf9OBRiu8Y5WFCGmMNcp0RYWlxw8A4/view?usp=sharing
I am the original owner of a 2006 LS430 currently at 42K miles. Recently, there is light knocking inside the transmission bell housing when in Drive (1st gear) or Reverse gears whenever the brake is applied or initially getting started on an incline. No knocking at all when Toyota WS ATF is below 130F temperature. No problems shifting and no knocking sounds after it gets moving beyond 1st gear. I think the source of the knocking is in the torque converter as we have a long very steep driveway which we use reverse gear to back up on to enter into our home garage and we may have overstressed the torque converter. There is no check engine light. The engine is a V8 3UZFE 4.3L VVTI with a 6-speed automatic transmission. I have dropped the original ATF from the pan and refilled back the same volume back with new WS ATF and double-checked for proper ATF level between 113F-130F.
Is there something I can do to make the knocking stop by methods by myself at my home like changing a specific solenoid?
Any idea which part of the torque converter is making this knocking when ATF is warmed up?
Thanks so much for your time, experience, and help.
Well you are on the right track. I'd suspect lock-up in the converter, what's rpm doing during this time? Rock solid? If so, I'd lean away from TC. Low miles and nice car so I would keep an eye on it and if it gets even a tad worse, use that toyo trans guy you've found to take it apart. Um, can't recall if you can see park pal with the pan off....I imagine you looked close and it and the trans was clean as new inside? How much metal in bottom of pan?
@hillbilly
Thank you so much for sharing your knowledge and experience. Thanks for your suspicions on the "lock-up" in torque-converter. I will research more in that area.
Knocking is noticeable at 1K rpm or less when ATF is warmed up and in gear. I have tried chocking the wheels, engaged parking brake, pressed down on brake pedal, and applied gas slowly while in gear. I notice the knocking is gone if beyond 3K rpm and knocking comes back when below 1K rpm after I let off the gas pedal.
The ATF was dirty when I dropped it from the pan. I noticed there was a slight metal deposit goo on the magnets but no shiny metal pieces.
Car is low miles at 42K, but has been mainly driven on local streets with hills by my wife.
What is a "park pal"? Do you mean the park pawl pin? You think it is loose or broken?
What I don't understand is why is it knocking when the ATF is heated up and NO knocking when it is cold.
Even tho the knocking is not impacting the drive operation, it's just bugging me. LOL
Scotty's voice is echoing in my head to leave it alone and to just drive it. hahaha
Yes, pawl...fingers....
And yea, Follow Scotty on this one but get prepared by having a trans mech (researched one) handy ; )
https://drive.google.com/file/d/1OmyZsvTFbUluajY5vvufDt050fZ00EYd/view?usp=sharing
Here is a longer video showing no knocking when in D gear when ATF is cold and the knocking begins when ATF is heated up.
First half of video when ATF is cold there is no knocking. Second half of video, there is the knocking and more frequent at the end of the video as the ATF heats up.
Why would increase ATF fluid temperature cause this knocking?
@ls430-4runner-driver
Ok, listened to it.... note above comment and follow that...second part if ya decide to spend $
As for when warmed up, components have expanded to their (supposed) operating dimensions/parameters so clearances/passages have changed some. Not to mention that heat is likely having a more significant affect on the failing component.
Thank you for sharing your wisdom, HillBilly! OK, I will start shopping around for a Tranny Mech.