Maf86

Hi Krzysztof,

I never did. I read that it shouldn't be changed.

Did you had the same issue "slow/delayed transmission response"? and if yes, does changing the oil resolved it?

cheers,

Thanks for your quick reply Giles,

My car done 133k, and there are no visible leaks on the gearbox.

now i am just waiting the bearings, once arrived i will install them.

will keep you updated.

Cheers,

On 12/25/2014 at 7:49 PM, Hayne said:

I should also mention what to look out for when your pump is due to fail.

These are my experiences;

About 2 months before my hybrid transmission oil pump failed, I particularly noticed a slow response when the gearbox changed the CVT torque multiplier ratio (i.e. equivalent to an overdrive gear).

About the torque multiplier: At about 55mph, the gearbox changes the ratio of the CVT to the high ratio (you will notice a short drop in power of about half a second) before continuing to accelerate. When decelerating below 35mph, the torque multiplier changes to the low ratio (again, you will notice a short drop in power/engine breaking, while this changes).

At this point, if the pump bearing is worn, the change is slower. This is most noticeable under hard acceleration, where the change can take a couple of seconds due to the pump motor struggling to turn properly, causing slower pumping of the transmission fluid (it is worth experiencing this now so you know what to look for in the future). I experienced a couple of times, the dash displayed the message 'Hybrid System Overheating' during hard acceleration. This too, was the pump failing to supply enough pressure to change the torque multiplier ratio in time. To try and overcome this just before my pump failed, I began taking my foot off the accelerator at around 55mph, just to give the pump a chance to supply enough to change ratio.

About 2 months later, while driving in electric only mode, the pump bearing seized and caused the car to grind to a halt, as there was no pressure.

If this does happen to your car, don't panic, just power the car off using the power button, then power on, wait for the READY light to go steady (takes about 10 seconds under the fault condition), then drive away as normal. The car will just be running in petrol engine only mode. The dash will show 'Hybrid System Fault'. The car will not drive at above 75mph. I drove my car with this fault for 5000 miles before I repaired it.

So, to summarise; if your car changes the torque multiplier ratio quickly under hard acceleration at about 55mph (could be up to 75mph, depending on acceleration), then the pump is functioning correctly. If you notice slow changes, or the overheating message, its worth replacing the bearing anyway.

I hope this will give GS450h owners a little more confidence as to the state of their pumps and what to look out for.

PLEASE NOTE; THIS IS JUST A SUMMARY OF MY EXPERIENCES AND MAY NOT APPLY IN THE SAME WAY TO YOUR CAR.

Giles.

Hi Giles,

I am experiencing quite a similar issue with my car, as you mentioned I am also noticing  a slow response when the gearbox changes the CVT torque multiplier ratio especially under hard acceleration for the last 2 or 3 monthes, But in my case there are no error codes.

do you think that i should replace the bearing "I already ordered them online" ? or maybe the transmission fluid is low in my case?