Transmission Issues on 2020+ models??

[akbu]

Been having all sorts of transmission issues on our 2020 MXZ.
 

It worked great for the first 250 hours, then the transmission left us stranded and needing a tow about 4 separate times. The transmission was replaced with a brand new one, and now the brand new transmission has also left us stranded. Dealer is as confused as we are and is going to contact Malibu to see what next steps are. 
 

Dealer and service department have been great throughout the whole process, but it’s frustrating that we’ve had get towed in 5 times and have missed multiple weekends because of these transmission issues. Is anyone else having similar problems?

 

Thanks for any replies.

 

[shenard]

4 minutes ago, akbu said:

Been having all sorts of transmission issues on our 2020 MXZ.
 

It worked great for the first 250 hours, then the transmission left us stranded and needing a tow about 4 separate times. The transmission was replaced with a brand new one, and now the brand new transmission has also left us stranded. Dealer is as confused as we are and is going to contact Malibu to see what next steps are. 
 

Dealer and service department have been great throughout the whole process, but it’s frustrating that we’ve had get towed in 5 times and have missed multiple weekends because of these transmission issues. Is anyone else having similar problems?

 

Thanks for any replies.

 

Lemon law it just like a car and try and get a new boat

[csleaver]

What kind of problems have you had with the transmission?

[akbu]

Boat refuses to go into drive…we can get it to go into reverse but not drive. Seen all sorts of error messages like “trans temp high”, etc. 

Before the dealer swapped a new transmission in, they tried replacing the throttle, prop, and a couple other things but we just continued to break down after being told that it’s all fixed and good to go... So we thought the new transmission would be the final solution but nope.

Dealer also noted that our prop seems to be spinning/moving even when the boat is in neutral. This continues to happen even after they dropped in the new transmission a week ago. Service said they’ve never seen anything like it…

[csleaver]

The most common cause of transmission problems is improper fluid level.  The level can be properly checked with the boat in the water and the engine at normal operating temperture.  Shift the transmission into reverse, neutral, then forward and rev up to about 2000 rpms for a few seconds, put it back into neutral and turn off the engine.  Immediately unthread and remove the brown transmission dipstick, wipe it clean, and fully insert the dipstick without threading it in, pull the dipstick back out and check the level.  The fluid should be between the two marks on the dipstick.  This fluid check needs to be done within 30 seconds of turning off the engine to be accurate.

The M5 and M6 transmissions use Mercon Dexron type III compatible ATF and the LT4 engine uses type F ATF.

A pinched trans cooler hose, clogged cooler, or a leak that causes low fluid level can cause high fluid temperatures and can also cause clutch damage that will make the clutches drag and turn the prop in neutral.  This can also cause hard shifting.

[Surf4FamFun]

27 minutes ago, csleaver said:

The most common cause of transmission problems is improper fluid level.  The level can be properly checked with the boat in the water and the engine at normal operating temperture.  Shift the transmission into reverse, neutral, then forward and rev up to about 2000 rpms for a few seconds, put it back into neutral and turn off the engine.  Immediately unthread and remove the brown transmission dipstick, wipe it clean, and fully insert the dipstick without threading it in, pull the dipstick back out and check the level.  The fluid should be between the two marks on the dipstick.  This fluid check needs to be done within 30 seconds of turning off the engine to be accurate.

The M5 and M6 transmissions use Mercon Dexron type III compatible ATF and the LT4 engine uses type F ATF.

A pinched trans cooler hose, clogged cooler, or a leak that causes low fluid level can cause high fluid temperatures and can also cause clutch damage that will make the clutches drag and turn the prop in neutral.  This can also cause hard shifting.

is there any way for a shredded impeller to make its way to the transmission cooler?

[Steve B.]

54 minutes ago, Surf4FamFun said:

is there any way for a shredded impeller to make its way to the transmission cooler?

On lots of these boats yes. On this particular setup though I can't confirm. But, on most boats that is the first thing to check for with temp issues. It can be impeller parts or seaweed or other debris gets caught in there.

[csleaver]

The M5 and M6 transmission coolers use the engine coolant, not seawater, so it is very unlikely that impeller pieces can directly effect the cooler.  The main engine heat exchanger can get clogged with impeller pieces or be affected by low sea water flow and that could cause higher engine coolant temperatures.  Low coolant levels or air trapped in the cooling system could cause a problem with the trans cooler.

Over filled or very high transmission fluid levels can cause aeration of the fluid and also cause them to overheat.