2005 TRANSMISSION FAILING.. MODLE # A5S 390R YZ

[andrewwynn]

We had a Mercury sable that had a defective solenoid for torque converter lockup. The symptoms sound identical.

We would get a code related to the transmission slipping in high gear on long drives.

You can tell if the transmission is not locking up by getting up to highway speed and then slightly accelerate from say 55 to 58 mph. The tach should barely move. If the tach rises and settles back down, transmission is not locked. This could be the actuator or the torque converter.

[c-bass]

Originally Posted by andrewwynn

We had a Mercury sable that had a defective solenoid for torque converter lockup. The symptoms sound identical.

We would get a code related to the transmission slipping in high gear on long drives.

You can tell if the transmission is not locking up by getting up to highway speed and then slightly accelerate from say 55 to 58 mph. The tach should barely move. If the tach rises and settles back down, transmission is not locked. This could be the actuator or the torque converter.

The ZF tranny in my e46 330 has the solenoid issue

In the case of the ZF tranny the issue is generally not with the solenoid going bad as much as there is a seal in the torque converter that won't allow the tranny to hold the necessary pressure to engage overdrive.

Unfortunately there is no way to service this part as it's inside the torque converter.

If I was in your shoes I would first start off by scanning the codes with an ODB reader. A cheap amazon bluetooth device will give you a better idea what is going on.

Next up I would check the fluid level, which is a pain in the ass because there is no dipstick. you would have to get the trans up to temp and then check the fill hole. There should be a slight dribble of fluid coming out if it's at the proper level.

A transmission fluid flush and filter change can definitely help as there is NO SUCH THING AS LIFETIME FLUID.

Failing that, you would have to decide how long you want to keep the car for and "invest" accordingly.

A good friend of mine who is a mechanic went the used transmission route...twice, before he bought a brand new one from the dealer and called it a day.

If you want to keep the vehicle around for a while then I would seriously consider a new or fully rebuilt (with warranty) unit.

If you're uuhhh....let's call it adventurous, then swapping transmissions can be a fun way to spend many hours

For transmission fluid many many people use the Valvoline Maxlife with great results. No need to buy magic BMW fluid because these are GM and ZF transmissions found in many non magical cars.

Good luck