Toyota Vitz CVT Transmission Valve Body Servicing

[saqib38]

[capsat]

@saqib38 you have messed up a thread for transmission - use some wisdom flag tyour post and ask moderator to move it to respective section for Hybrid / technical section
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49 error code is for a switch at brake pedal which activates the push start
41 one is for low voltage at primary 12 V battery

read this as well

[rajaatta]

this is CVT transmission related thread.
but the errors are intermittent just erase them

[saqib38]

@capsat @rajaatta thanks buddy and really sorry for posting over here

[viv_bowan]

well sorry for late reply i was busy on some project's. the cvtf fluid overheating is mainly caused by main pressure regulator if it's stucked or had enough residue's formed by deteriorated oil itself. also the main belt clamping pressure drop's causing poor performance and overheating issue's.

it can easily be diagnosed through tech stream diagnostic tool where we analyze the oil CVT oil temperature's and line fluid pressure's. and can simulate the active test for belt clamping pressure analysis and as described in the thread already if it's low then you need to service the whole valve body assy. And the problem would be resolved. But if the pressure is low along with symptom's of no forward movement or slipping shredding then you had to rebuilt the whole transmission.

the cooler design on K411 ,410 CVT is On transmission cooler's mounter on the outer body of transmission's where the coolant only move's in and out in cooler line and a thermal separator is present in it where Fluid move's same principle like old style cooler's which were present in radiator tanks. this cooler design does create a lot of trouble if the pressure drop's below the normal operating range. so to avoid it always keep the line pressure up to normal or near normal range.

@rajaatta I was unable to check the belt clamping pressure. I plan to get the TechStream software. To date I have flushed and renewed my coolant with some improvement to the overheating/whining noise experienced when the CVT is pushed hard. The coolant (Toyota Super long life coolant) was mixed with green (Prestone). I could see the separation with the green floating on top. The contaminated coolant has a consistency of a thin syrup. Radiator was flushed with a radiator flush and distilled water. Refilled with Super long life coolant and whining is not as prevalent even with aggressive driving. With your experience and expertise, would you say that mixing these coolants can have a negative impact on engine/transmission cooling? I have not experienced any overheating warning lights, just the transmission noise when pushed hard.

[luckycar]

Dear folks
i am going to change transmission oil for my vitz 2009/2010 model. Mechanic says Toyota genuine transmission oil CVT Fluid TC 08886-02105 4L gallon. Please suggest.

Secondly, T/oil filter is also need replacement as mechanic says it will be cleaned and no need to replace.

Awaiting yr suggestion.

[waqas.rasheed]

possible reason of jerk from P to R only in Automatic Corolla GLI 2015?

Recently Tx oil was flushed with Kixx DX-III (a compatible oil of Toyota Standard ATF T-IV). So there is no issue of compatibility.

Initially Tx fluid was not changed till 70K ODO by previous owner. Jerking was also observed before the flushing. Tx fluid pressure was improved from 1.7 MPa to 3.0 MPa after flushing but jerk is still there as soon as Gear shift from P to R or From N to R. This happen only in reverse(R).

any solution to avoid jerk? as I don't want to perform the valve body service at this stage, as I have serious doubts of getting it worse after opening as it is a highly sophisticated part.

[babarhyd]

Have u checked the mounts?

[waqas.rasheed]

Mounts are in good condition. If the culprits are mounts then jerk will also felt in [D] mode as well. but Its not a case. Jerk is observed only in shifting to[R] Mode.

[rajaatta]

if the jerks or late shift in R is observed after complete fluid flush then its time to service the valve body assy the as the Reverse fluid control valve is sticking and need's to be jammed cleared off other wise the condition will get worse if left untreated and can lead to the damage of reverse band. its not a complicated job and nothing goes in the worse scenario i would suggest you to go for it.

[rajaatta]

no need to replace the Oil Retainer in the pan it is fabric mesh type filter and is good for the 100 k interval just wash it off with good amount of kerosine oil and in bakward flushing not upward.

for toyota CVTF try to avoid it and go directly for kixx CVTF

[Moderator]

This post was flagged by the community and is temporarily hidden.

[viv_bowan]

@skylarks what symptoms do you experience when the CVT runs at 95•c continuously??

[haseeb.basharat]

Reason to avoid toyota cvt-fe oil?

[skylarks]

Well, symptoms are Pretty Normal... as i can measure a descent Belt Clamping Pressure at 80C, it means things are going good.

Normal Operating temperature for an automatic transmission to work is almost same as the engine temperature 90C to 95C. When we already know that this particular Transmission is cooled by an Engine Coolant flowing in a closed loop system through a heat exchanger (Cooler).

A hot climate, heavy towing, bad ATF fluid and any problem with transmission itself can be some reasons for the temperature to rise above the operating range...

HINT: Radiator Fan starts automatically as soon as Engine/coolant Temperature reaches 95C.

Note: The text above is based on my Observations and Understanding

[viv_bowan]

@skylarks I have a Toyota Vitz 2014. Sometimes on long uphill climbs and aggressive driving, I would experience a loud whining sound coming from the CVT transmission. However, when it cools down and under normal driving conditions there is no such whining sound. Do you experience this? I was advised to check the fluid pressure but I haven't yet done so because I do not have the software. What I have done though is to change the radiator coolant since I observed it was mixed with green coolant and the coolants seem immiscible with the green floating on top of the pink. I performed a chemical flush and then distilled water flush before using the original Toyota Super Long Life Coolant (pink). I have subsequently done aggressive driving and hill climbing (I am in the tropics) and no such whining. When the contaminated coolant was drained, it had a consistency of thin syrup. Some research also indicate that extreme oil temperatures can also cause cavitation. "High temperatures allow vapor cavities to form in the fluid. Cavitation is the formation and collapse of air cavities in liquid. When hydraulic fluid is pumped from a reservoir, a low-pressure drop occurs in the suction side of the pump. Despite what many people believe, the fluid is not sucked into the pump but rather pushed into it by atmospheric pressure. Hydraulic oil contains approximately 9 percent dissolved air. When a pump does not get enough oil, air is pulled out of the oil. These air bubbles travel into the pump and eventually collapse and implode when they reach an area of relatively high pressure. The ensuing shockwaves produce a steady, high-pitched whining sound and damage to the inside of the pump". This demonstrates that the condition of the coolant is of great importance and should not be ignored. I have shared my experience to increase the knowledge base and also for any critiquing and commenting.

[rajaatta]

unstable fluid in extreme high temperature's causing it to detoriate and build micro residues to block the movement s of the valve body assy Piston's and regulator's.

[haseeb.basharat]

So what to use instead of cvt fe?
Liqui moly atf 1400?

[zia1288]

[haseeb.basharat]

Using cvt-fe and will keep on using the same.