Toyota Vitz CVT Transmission Valve Body Servicing

[rajaatta]

do you do the uphill driving in D position ???
If yes then it would the same behavior you had mentioned
On Uphill driving conditions always drive in S mode or on more steep up hill Drive on B Gear.
you problem would be resolved.

[skylarks]

@rajaatta
Aoa Atta Bhai, Hope you are doing good. A very informative article indeed...!
I have a questions please...

What is the normal temperature range of A/T Fluid when the CVT line Pressure could be measured on idle?

Thanks

[rajaatta]

the ideal temperature on which we measure the belt clamping line pressure is 80 degrees centigrade.
at idle

[skylarks]

So when line pressure of 3.2 MPa at 80 C on idle is sign of a healthy transmission and healthy ATF, Temperature will rise for sure when Vehicle is moving and pressure will drop if temperature is above 80 C, what is the max limit the ATF Temperature shouldn't exceed and is considered safe, if for example vehicle is driven 60 kms. (driving conditions: normal)

Thanks.

[rajaatta]

No if the pressure is in good range and the service history is unknown than we had to analyze the color of CVTF Fluid and decide whether to replace it or not. the normal Operating temp is max 90 C. the temp should cross the 90c when transmission is pushed harder and cools down immediately when load is absent if the temperature doesn't drops down after load then there is something wrong in cooler bypass valve circuit. which we had to address that issue immediately.
so a normal healthy CVT Transmission with a normal start and 60 Km's trip driving in summer's the CVTF Temps is maintained at MAX 85C max with a little bit of load pushing including and if driven totally with light foot than the CVT Temp doesn't cross 82C .

[capsat]

The failure of CVT happens when -

Radiator cleaning is performed and coolant flow tubes are disconnected by USTAAD .. yeah hamary mulk mai baykar hai Ghyr buxa ka paayp ko u turn kar k wapas Ghy buxay mai joor doo.

[rajaatta]

welcome back mate !
its being long time since we had some discussion.
well for normal auto transmissions they do this trick and waste the transmission.

But in these CVTs they are helpless to find the line...... and this is where they got confused and cant do their tricks.

wesay pipe ghuma kar laganay mein mistariyon ko maza bara aata hai .... lolzzzzz

[Xulfiqar]

waste is a nice word - they turn it into scrap metal.

btw - CVT are my nemesis, 99 out of 100 Jatco CVT units I check have a scragged pulley sheave cylinder (where the ball bearings ride) - I had only two that are back on road after small repair, one was a collapsed filter and one was a wiring issue (mouse chewed on it) - the rest were toasted to oblivion (all had more than 160K kms)

[rajaatta]

Welcome welcome welcome
Our Boss its along time had not seen you boss and not talked to you yes yes you are right they are happy to turn it to scrap and install a scrap kabuli one in place of it ........

boss i had a query

i am stuck in BMW x5 4.4 ZF type transmission recently received the vehicle with problem of main fluid pressure line loss after steep hill climbing on normal road its fine and temps are also fine. Inspected every thing in it on systematic bases.
Now had a last option of toring down the whole transmission and rebuild it fully what do you suggest boss.

[Xulfiqar]

Do you have all 6 ratios applying?

Line pressure loss can be from a worn out clutch E bushing or a sticky valve body - the other problem is the actual ATF being used. (I belive you can use toptec 1800)

Is your electrical system clean - check for too much AC voltage at the alternator. It can cause some really idiotic problems.

[skylarks]

Atta Bhai, I have some test results to share with your good self.

1) High Pressure Reading was fluctuating between 2.9 MPa and 3.055 MPa at 80 C. Low Pressure Reading was 0.3 MPa. (I did Cold Start and measured the Pressure on Idle with AC OFF)

2) I drove my vehicle back home from Office (Distance is 60kms) with AC ON, on light foot & no extra load. High Pressure Reading (on idle with AC OFF) was fluctuating between 2.0 MPa -- 2.2 MPa and AT Fluid Temperature was 95 C. Low Pressure Reading was 0.3 MPa... Is it normal, your expert opinion please!

Screen Shots attached for your reference...

Service History: CVT Fluid was changed and Valve Body was Serviced at Rehman Autos almost a year back when mileage was 68k and current mileage is 98k.

Software used is Toyota Techstream 10.30.029 with mini VCI Cable.

Thanks...

[rajaatta]

It seems to be fine at 80C but after driving it 60Km distance the temp goes on 95C doest it cools down after travelling????
what were the precautions issued by rehman auto's if any?

measure the temperature after driving. and observe the temps do they go down or not or they stay on the same temp or raise from it.

[rajaatta]

got it boss i do suspect the ebushings and AC voltage of alternator. will update after diagnosis. thanks boss your opinion is always perfect for our learning's.

[skylarks]

I did check the AT Fluid Temperature after i drove back home today, it was 95 C for almost all of the time, raised to 95.6 C for some seconds and was stable afterwards at 95 C. I monitored it for 15 minutes approx.

As for the precautions issued by Rehman Autos, CVT Oil Change was advised after 25k kms, i.e at 93k on the clock while current mileage is above 98k.

Thanks.

[rajaatta]

it seems to be deteriorated CVTF fluid if the temperature doesn't cools down from 95C.

[ab6666]

Are you importing these rebuild kits for transmission? Because as far my info these are not available in Pakistan.

[taimoorali.khn]

Hey guys, can anyone please recommend a good mechanic in Karachi( preferably in DHA or Clifton) who is an expert in changing CVT gear oil of Toyota Passo?

[capsat]

0300 223 7538 Irshad

[viv_bowan]

Thanks @rajaatta

[saqib38]

aslam o alekum guys
can anyone guide me for the below error code.
sorry i'm new with hybrid car and ABS sk not aware off.