On our old 3.3L Hyundai sonata, backup car I have it narrowed down to worn lockup solenoid valve body, which I think it is or a worn torque converter clutch.
The car is 2008 with 270,000 miles on the transmission, nearly all highway miles.
I'm thinking if I dump out some of the transmission fluid and replace it with say some AW iso46 hydraulic fluid and it is a leaky solenoid; could the thicker fluid keep the transmission line pressure up assuming it's a solenoid/valve body enabling the converter lockup to stay locked up or at least locked up longer?
And if it's a worn torque converter clutch thicker fluid won't matter.
I'm not saying this is or could be a fix. Either the p0781 code goes away and I install a new or rebuild valve body, flush the fluid, ect or it doesn't. Even then I say it's a 50/50 chance I part it out or junk it from there.
The dealer is absolutely useless, all they'll do is replace the torque converter for like a thousand bucks and they can't get a valve body.
The local transmission shop reached the same conclusion as the dealer and as I did for a diagnostic fee of $100, it's probably the valve body which they can't get or it's the torque converter.
I have a place that might be able to get a valve body or rebuild mine with steel sleeves. Either way I would like to know for sure one way or the other before I go all in.
The car is 2008 with 270,000 miles on the transmission, nearly all highway miles.
I'm thinking if I dump out some of the transmission fluid and replace it with say some AW iso46 hydraulic fluid and it is a leaky solenoid; could the thicker fluid keep the transmission line pressure up assuming it's a solenoid/valve body enabling the converter lockup to stay locked up or at least locked up longer?
And if it's a worn torque converter clutch thicker fluid won't matter.
I'm not saying this is or could be a fix. Either the p0781 code goes away and I install a new or rebuild valve body, flush the fluid, ect or it doesn't. Even then I say it's a 50/50 chance I part it out or junk it from there.
The dealer is absolutely useless, all they'll do is replace the torque converter for like a thousand bucks and they can't get a valve body.
The local transmission shop reached the same conclusion as the dealer and as I did for a diagnostic fee of $100, it's probably the valve body which they can't get or it's the torque converter.
I have a place that might be able to get a valve body or rebuild mine with steel sleeves. Either way I would like to know for sure one way or the other before I go all in.