Hi guys. Sharing what happened to my wife's 2018 rx350L at around 57k miles, around 2 weeks ago i heard some rattle noise coming from the motor, when i opened the hood to check where it was coming from i noticed black stains under the top motor mount and also some (oil type) liquid dripping from it, took it to dealer next day i pointed out the rattling noise and the leak coming from the motor mount which the SA diagnosed right away to be the water pump making the noise and the black stains and leak to be coolant or condensation from the ac which didnt make sense to me, after telling him over 10 times to please check the motor mount for leaks he said not worry that the tech would check everything out, next day they called to say car was ready and fine now, after my wife brought the car home i inspected the engine bay and found that the black stains and leak from motor mount was still there, called dealer and the SA told me again not to worry about the black stains and leak thay it was normal, prob water from rain got stuck in there but i could bring the car back which i did and showed him again that the leak was coming from motor mount, then he called a tech to speak to me, i showed the tech the leak even grabbed the motor mount from the bottom and showed him it was coming from there, then he said no way the motor mount leaks it could be just coolant left from the water pump replacement or prob water from rain basically repeated same thing the SA told me, then SA comes out and tell me they could check the motor mount but i would have to pay $220 for the diagnosis,



at that point i was super frustated with their service, i asked him why when they did the water pump replacement and remove the motor mount and saw the leak they still decided to put it back like that and not put a note on the service record or tell me that indeed it was leaking.... he said technician checked and it was good ..... after over 2 hours of trying to make them understand i decided to ask for the service manager, right after i asked for the manager their attitude changed and decided to finally accept that i was right, waited another 15 mins for him to come back and tell me that it would be cover under warranty, car is back with a new motor mount and no more leak, hope this doesnt happen to any of you

 

Can you go to a different dealer next time? That's unfortunately quite typical, see a problem say oh that's normal don't bother to do anything about it until you force their hand.

 

I never knew motor mounts could leak. Are they filled with fluid like a shock absorber?

 

Concur. I have never heard of a motor mount with a coolant chamber or gasket. There's something more to this one -- the motor mount is where the coolant ended up dripping off, but where did it originate? Did they fail to mount the replacement water pump correctly, or what?

 

Liquid filled mounts are fairly common.

 

Ahhhhhhhhhhhh -- I see it now. I feel so old ......

 

Getting old is far better than the alternative.

I think liquid filled mounts are extremely stupid and do little if anything to reduce vibration. And they leak.

 

Even my 2002 Highlander has liquid filled engine mounts. They use hydraulic fluid to actuate a diaphragm, which is supposed to make idling more smooth. The driver's side (transmission) mount failed on my car and I replaced it while I had my car apart to replace the control arms. Used one from a 2015 RX350 and the design was still identical, it fit right in. No more rattling at stop lights or harsh shifts!

 

Yes next time i will try a different dealer for sure

 

yes some motor mounts are liquid filled

 

i guess the motor mount failed around same time as the water pump, the coolant leaking idea was from the SA, i knew the leak was coming directly from the motor mount which he kept denying, but im glad i was right and they replace it under warranty

 

yes sir. Its crazy how they were solid denying that it had no liquid in it when you could clearly see it coming from there

 

Idle vibration had increased a lot with the leak issue, now car feels really smooth with the new one

 

Toyota's liquid filled mounts have been around for quite a while. When we purchased our 1997 Avalon, they touted the liquid filled motor mounts as a feature that was "borrowed" from the Lexus LS.

 

Also the motor & tranny mounts are recommended to be changed at the same time, unless one of them goes very early, they are viewed as consumable and are supposed to work together.
1st time I heard of these being consumable was when I owned a MB.