No announcement yet.

Procedure to change Auto Transmission Fluid in 6 Speed Transmission (Hilux/Fortuner)

  • Filter
  • Time
  • Show
Clear All
new posts

  • Procedure to change Auto Transmission Fluid in 6 Speed Transmission (Hilux/Fortuner)


    As most of us who own 4WD's we are serious about preventive maintenance. There is no such thing as a sealed for life transmission regardless of what car makers tell you. It has caused thousands of failed transmissions in all types of vehicles. One example is the CVT issues on VW that needed changes every 30K but owners or mechanics didnt drain fluids until the boxes were pulled from the car after breaking down. Another one is the ZF disaster from 1997 to around 2010 on European cars. It made transmission repairers rich from all the rebuilds to this day. Also with Aisin from Japan and the failures go on....

    So with our Toyota's what do we do as they have no dipstick and an awkward fill plug apparently stuck to the side of the box requiring wheel removal and part of those plastic splash shields.. Then there is some complex fluid level adjusting procedure. I looked at a few Youtube videos on other Toyota vehicles with a similar set up on Lexus and US Tacoma/Tundra vehicles that have this idiotic system that frustrates the home mechanic. But I do not know if the Fortuner/Hilux untis are similar.

    I took my Fortuner for its 50K service yesterday and the Service Manager (which in my experience are failed mechanics who have been promoted to higher levels of incompetence) was totally clueless re the transmissions. " We have never done one". "I dont think we even have the right oil here to work on them" "Take my advice and dont worry about it till you get to 100K" "Do you do much towing? Not really, then dont worry about it, Toyota stand by their advice that they are filled for life" on went the Service Manager.

    I asked him how much would it cost. He said about $500 to $600!!! I looked at him trying to hide my bewilderment. He commented he needs to flush the transmission about three times to ensure the old fluid gets out.

    The right fluid is the Toyota ATF WS where the WS stands for World Standard. I researched this a little bit and it is not even a Synthetic fluid. I looked at the Oil companies lube recommendation for these transmissions and they recommend the Penrite ATF LV or Castrol Transmax FE Multivehicle ATF amongst many other brands that would be available....where on the spec sheet it is stated they all meet the Toyota WS and these are all Group III synthetics.

    So has anyone attempted to drain and refill these automatic transmissions? And if so how do we do it? I am sure there are some high mileage Hilux's that have exceeded 100-150K already since their August 2015 release where owners have performed a service. It is recommended that fluid in the transmission pan be drained every 60K maximum which is about 3-4 litres. Dry fill is 9.5 litres, So what i used to do is drop whatever AT fluid every 3rd engine oil change to ensure the fluid stays fresh. If this is not handled properly I predict much failure and expense for owners of the as these transmissions already have some gear shift issues as mine has.


  • #2
    When I fitted the external oil cooler if drained then flushed whilst running through the gears till oil came clean out of the pipe from cooler, refilled and adjusted fluid levels.

    fill plug on side is easy to get too and use a pump to fill. Gearbox needs to be between 35 to 45 degrees. I have the procedure to set dash indicator but used scangauge2 instead to temp.

    better to flush rather than drain /refill due to you will always have old oil in there.

    used about 12 ltrs all up


    • AlexV
      AlexV commented
      Editing a comment
      Thanks Spook, what oil did you choose? I will have to check out the correct exit pipe for the AT to the cooler and unhook it......did you have your vehicle up on a hoist?...

  • #3
    I used the Penrite LV
    The pipe on drivers side is one I used. If I remember correctly pumped back into the pipe going back to gearbox, hose from radiator cooler went into big pan. You will need s pump for 20 ltr container to get volume needed. You need someone to run it through gears with foot on the brake and you pump as hard as you can but don’t blow pump hose off, so clamp it.
    do this till comes clean. Took me 3.5 ltrs I think.
    top up gearbox till it comes out fill tube plug, get gearbox to 40 deg then with fill tube plug out and engine running fill gearbox till fluid poor out fill tube plug. Once most volume stops flowing put fill tube plug back in. It’s fine and recommend to overfill by half a ltr with this type of gearbox. Lesss chance of gear slippage between cold gear changes.

    clean up mess😂

    sure I put more detail in a trans cooler thread.


    • Spook1205
      Spook1205 commented
      Editing a comment
      Vehicle was on hoist but at ground level for this

  • #4
    Does Toyota sell a Transmission filter kit? Autobarn etc dont offer one.

    I had the vehicle up on the hoist when changing tyres yesterday and I can see the 24mm ill plug on the drivers side in a tight spot next to the exhaust pipe and heat shields..


    • #5
      Wholesale Automatics do a kit that bolts straight up. It’s a sweet bit of kit👍
      In the GX there is lots of room, other models the grill may need a small trim on inside.
      toyota do not make a kit to bolt up.

      the 24mm plug is pretty easy to get too, more of a pain getting to clamps on radiator cooler outlet.


      • #6
        I performed an "oil change" this morning on the transmission while warm. Disappointingly only 1.9 litres came out of the drain plug where past 4WD transmissions around 4 litres came out hence the inverted commas.

        The colour of the fluid was a dark coffee after 51K compared to the new bright red ATF that went in (Penrite ATF LV @ $45 a 4 litre pack) I used a small plastic $20 pump that fits onto the oil container and simply pumped the oil into the fill plug where in my case an old 15/16 socket fitted more snug than the 24mm. I just observed the clear level on the side of the oil pack to see when to stop.
        I also simply pulled down the thin alloy heat shields around the exhaust to get better access and then pushed them back up again.

        I pumped in about 2.6 Litres as apparently these units are under-filled from the factory. I will see how the trans shifts when cold in the morning

        Next few days when the trans is warm again will open the oil level plug with the engine off and see if fluid comes out. I believe it is necessary for any DIY owners to perform this operation every 20K and top up 2 liters to keep their trans fluid in good condition.
        So for around $25-30 worth of items (fluid & pump) every 20K your transmission can be saved from a long term financial disaster costing around $4-5K for a change over trans.

        I am lube blender/formulator/chemist by trade (as my passion from young was preventative maintenance/reliability engineering) and was part of the team 22 years ago to formulate the so called "filled for life" fluid for the ZF transmissions on MB/Audi/BMW and the OEM car makers chose a semi-synthetic ATF71141 formulation, not even a full synthetic based on PAO or even the more common today Group III hydro-cracked fluids....even though full synthetics were required for their engines and diffs and our team warned the ZF about this.
        This turned out to be a global disaster!! Once these transmissions reached 50-60K they started to fail or shift erratcially. Transmissions that made it to 80-100K simply imploded into expensive scrap metal. I inspected dozens of these transmissions during disassembly and the fluid when new was a bright fluorescent yellow and it was dark brown and very rancid in odour.
        To illustrate the magnitude of the problem A&B transmissions who worked in a small backyard premises in Mordialloc in Melbourne within 4-5 years went to a multi-million $$ facility just to keep up with the rebuilding of these transmissions from the income (profits) generated off the car dealers who then claimed back from their German makers. Similar operations opened up in every capital around the country and became massively profitable. One other example was the Borg Warner 85/95LE transmissions fitted to 1990 and later Ford Falcons literally kept some AT repairers in business from bankruptcy during the recession at that period. Many didnt understand the change n fluid from DEX II to Mercon !V and ATF 95LE..... and also the internal hubs used to self destruct after the circlips failed.

        Transmissions of these types require an oil condition sensor fitted s standard as some GM engines in the USA have for engine oil as disaster prevention. You do not change the oil until the ECU detects a drop or increase in viscosity or soot/metal contamination. An example of one aftermarket unit is here :

        The Filled for Life fluid for transmissions are a myth that will cause Toyota much heartache down the track. Recall Toyota wanted to quote me $500-600 for an oil change/flush. The issues for owners financially is when the vehicles run out of warranty.


        • Tbhawk
          Tbhawk commented
          Editing a comment
          Hi Alex, so mixing the genuine oil with the synthetic Penrite is ok?

      • #7
        I finally got around to checking the oil level after the fluid change a few days ago when the transmission was around the 40-45C. I was surprised when i opened up the oil level plug and when I measured it 2 litres of oil came out!!! I was simply shocked.

        It means that the fluid was overfilled by around 1.4 litres at the factory who made the transmissions as these are delivered to Toyota in Thailand as sealed filled units ready to bolt on, as if you recall from my previous post I added an extra 600ml of ATF onto the 1.9 litres that i measured that came out the drain plug.

        I also asked the dealer at the 10K service to check the oil level due to cold shift issues. I looked at the old invoice and it states they did but obviously they didnt. I drove the vehicle after adjusting the fluid level and it definatley feels different. Perhaps Fortuners and Hiluxs suffer from overfilling issues.


        • #8
          I recently installed the Wholesale Automatics kit. The gearbox now runs 20-25degrees cooler at around 85degrees towing the van. Very happy!! The first thing I did was to remove the level plug, no fluid came out. When I disconnected the hoses to install the kit approx 100mls drained out. After installation I added about 1200mls of Toyota WS fluid before it started to drain from the level plug. I doubt the cooler would account for the additional fluid. The cold shift issue has now disappeared. I can only assume that the gearbox was not filled to the correct level.


          • Spook1205
            Spook1205 commented
            Editing a comment
            Honestly it’s most likely the main issue with cold shifts. Low fluid level and being cold is a classic symptom of that.
            I think its easier for Toyota to blame TCM so let’s give it a reflash rather ooops oil is low and we never check it.

            Glad you like the cooler, I was very impressed with it too.

        • #9
          Does that mean that you can install the wholesale automatic transmission cooler without dropping the oil? I will just have to buy a couple of litres from a Toyota dealer to top it up? I’m asking this as I only have 8000km at the moment or would it just be better to replace the whole oil with the penrite? Thanks


          • Spook1205
            Spook1205 commented
            Editing a comment
            Yes mate you lose very little when you take off the 1 hose.
            You can get by with 1tr for the job.

            Wait till you have done more kms before flushing out.
            To flush out you pump oil in the return pipe whilst it’s getting pumped out by gearbox. Run it through gears and keep doing this till comes clean, mine took about 2.5 ltrs I think to do this. Plus original drain and refill, then top up. Not much left out of 12ltrs. All this info is in another thread.
            You would be better to take to auto trans specialists rather than Toyota to do this.

        • #10
          heres a video from a fella i follow on youtube on how to do flush the fluid on a 200 series it should give people an idea


          • #11
            So when would you blokes suggest is a good time to change the tranny fluid ?
            Just ticked over 40K on my GXL !


            • #12
              Wholesale automatics recommend every 40,000kms but some people say longer


              • #13
                If towing regularly 40000 for sure, if not towing a lot could leave it longer.
                What is important is that it does get done especially if giving the gearbox grief.
                personally I think periodically checking oil condition and make judgment from there works.
                I didn’t change mine till 80000 but only just started towing a van at that km range. By judging colour of the oil it was getting to the point where I would want to change it for long term preventative maintenance.


                • #14
                  C.A.T.S. (transmission specialists) in Sydney recommend every 40k. They're the sydney mob Wholesale Automatics recommended to me as installers of their kit.


                  • #15
                    Do the Fortuners have a filter or something that should be changed like the one in my old Commodore ?