No announcement yet.

Converting your Auto GZ20 to Manual, A340E to W58

This is a sticky topic.
  • Filter
  • Time
  • Show
Clear All
new posts

  • VasH
    started a topic Converting your Auto GZ20 to Manual, A340E to W58

    Converting your Auto GZ20 to Manual, A340E to W58

    Hey guys this is my writeup on how to convert your GZ20, i will be editing and adding pics over time as i havent finished my conversion yet (almost did but had to come apart again) but this is step by step how i would do it.

    Any constructive criticism or advice to put towards this guide is greatly appreciated. Enjoy!


    Converting your GZ20 from Auto to Manual, A340E to W58
    Ok firstly I will list the tools, parts, consumables and lubricants required for this conversion, The main sockets you will need are 10, 12, 14, 17,22 and 24mm. Same goes with a set spanners.

    Parts aka the important bits

    w57 or 58 Gearbox with bellhousing to suit your motor.
    Clutch to suit (throwout bearing will come with new kits)
    Flywheel to suit
    Clutch and brake pedal
    Clutch master cylinder (A70 supra)
    Clutch slave cylinder (ma61 supra)
    Manual tailshaft
    Spigot Bearing Part # is 9036312003 from toyota

    W5* series clutch alignment tool, splined ones are the best dont know how well the universal ones go. you can normally get the splined tools from any decent clutch place, mine was about $50 from npc in acherfield.

    1/4 " and 1/2" ratchet and set of sockets to suit (depending on your clutch you might need some hex bits i would recommend getting the socket ones as Allen keys suck).

    1/2 " Breaker Bar (may not be necessary depending on how big your ratchets are).

    1/2 " Torque Wrench

    *Extension bars for both sizes and is always good to have various lengths

    *4 x jack stands (note you can do it with less or some really high car ramps, but for safety reasons i used 4. But if you have access to a hoist obviously won?t need these or jacks)

    *2x trolley jacks 3 would be easier

    *Set spanners, see top of page for sizes (note the ratchet ones are better but you will need a set of standard ones for the top 2 bell housing bolts as the ends of the ratchet spanners are wider and don?t clear between the bolt head and housing. But if you don?t have the engine in the car your one lucky S.O.B and common sense would tell you to use a socket :P).

    *Side Cutters

    *Crimping tool/Soldering iron whatever you prefer

    *Hand light

    *Bleed bottle, easy to make just poke a hole in the side of a empty coke bottle and slide a piece of tubing into the side down to the very bottom, i found that wiper washer hose is the right size for the job

    *Drip tray or oil catch

    *75w-90w or 80w-90w gear oil, 2.4litres.

    *High temp grease

    *WD40 comes in handy with those stubborn bolts

    Install/Removal Procedure

    * I would suggest unbolting the top 2 bell housing bolts before raising the car as I found my hands where too big to fit up underneath its a bit of a chore to get them from the top as well but if you join a ring spanner to the end of an open ender it makes it a lot easier or even get a small handled ratchet helps to get it out once its been cracked. they are 17mm. I also recently found that taking off the rocker covers helps alot.

    * Undo the kick down cable from the throttle body its next to the accelerator cable dont get them mixed up the kick down is closest to the firewall and sometimes has a bit of red/orange plastic over the end I would slide it down to the ground as well so it doesn't get caught when you remove the box

    * (Its up to you when you install the slave cylinder reservoir, cylinder and pedals but ill list it here anyway), Remove the 3 rubber bungs next to the master cylinder 2 small and 1 big one in the middle that's where the reservoir goes, In my case the slave cylinder and reservoir was all assembled so I gently guided it down to the passenger side of the bell housing and gently inserted the reservoir into the hole and placed the metal piping into the clips (be careful not to bend these too much), there is also a small metal tab on the body underneath the car that the slave cylinder hose goes into for support you may have to disconnect it or using a small hack saw cut a small slit in it and bend one side and slide it in then bend back into place

    * Remove plastic panel from underneath the steering column (3 Phillips head screws, It's also easier to remove the little green light and the fuel cap release and bonnet release they have 2x Phillip head screws once removed they just slide out), you will see the 3 holes that the rubber bungs used to be in and the slave cylinder bolts and joiner for the pedal (requires pin and clip similar to brake pedal but smaller) Place 2x 14mm nuts and tighten up, Then install the pin and clip ( clutch pedal might need a little adjusting depending on what clutch you use)

    * Next to that remove the brake pedal, 5x 14mm nuts one is located directly above the pedal away from the main 4, there is also a pin where the pedal connects the master cylinder. Remove the clip and slide that out make sure you hang onto it for the smaller pedal if you don?t already have one. There is also a small plastic box with a connection to it off the to right of the brake pedal box, I think it's a 10mm from memory and just disconnect you will need to put it back when the small pedal goes on. Also remove the brake light switch connector.

    * Once the auto brake pedal is out takes a bit of wriggling (lift steering wheel up and move seat back as far as possible makes life a little easier) install the smaller brake pedal.

    * Removing the auto shifter involves taking the climate control unit out slightly doesn't have to be all the way there should be 2 screws then pull the shift surround out it will gently bend over the top of the shifter and unplug everything. There will be 4 screws holding the shifter in place undo these and it should pull out with the selector rod attached. (note that if some of you are lucky enough to have a completely un molested surround it will have to come completely out)

    * Jack up car as high as possible and position 4 stands, ramps are better but i found there not high enough for the gearbox to clear once its dropped

    * Unbolt rear section of exhaust, probably best to remove the whole rear piece i left it hanging but it can get annoying

    * Unbolt tail shaft from diff, 4 bolts with nuts will need 2 x 14mm spanners

    * Unbolt middle section of tailshaft 2x 14mm

    * Gently slide out tailshaft from back of gearbox

    * Unplug the 4 cables that go to the gearbox they should be hanging/positioned near the bell housing

    * Undo gear selector lever

    * Drain oil from gearbox sump, you dont have to but means less mess and its a little lighter when taking it out

    * Now assuming you have removed the top 2 bell housing bolts undo the starter motor 2x 14mm then the remaining bell housing bolts 17mm

    * At the bottom of the bell housing engine side remove the inspection plate and undo the 4 bolts that attach the torque convertor to the flywheel you will need to use a 14mm and also a 22mm socket and breaker bar on your crank pulley and possibly someone to hold it as you undo these.

    * Now that the only thing left holding the box in place is the gearbox cross member, get one of your stands or trolley jacks place it under the middle of the box and undo the 4x 14mm bolts holding the box member in place once that is out use your other jack and place it in the middle of the cross member now if you have another jack around doesnt have to be a trolley one just a standard one out of your boot will do, you might need a block of wood or something to raise this jack off the ground because it needs to be placed under the front of the engine and gently raise so the engine tilts downwards at the back.

    * Let your jacks down a little bit at a time and start to pull it out, go slow and watch the angle probably best to have a mate to help as it comes down or a big ass trolley jack.

    * Once the box is out and the torque converter is out undo the bolts holding the flywheel on and remove that.

    * Now I would suggest removing the old auto transmission fluid lines
    as they will just rattle about under there, not the easy things to manuever out i just ended up cutting them up into pieces with a large set of side cutters.

    * Now to install the spigot bearing in the back of the crank you will need to get one from Toyota and if you are extremely lucky you might be able to find one at repco. Because all autos dont have them and they are needed to support the input shaft from the gearbox so it doesnt rattle and wear unevenly. Part # is 9036312003

    * Grease up spigot bearing and install using socket to match diameter, gently tap in with rubber mallet

    * (If you have removed the metal spacer/pressure plate make sure you put it on before your flywheel) Install your flywheel and clutch I used a TS2B OS Giken clutch so depending on what clutch you have installation may vary also refer to the supra manual as it has all the factory torque settings and details for standard installs. You can view that here

    * Also remember before completely doing up the pressure plate you need to align your clutch with either a universal tool from repco/supercheap or get a splined tool to suit your setup, splined tools are required if you are using a multi plate clutch because if you don't line up the teeth have fun getting the gearbox in. Then proceed to torque up the pressure plate.

    * Now youre ready to install the gearbox but first get some high temp bearing grease or something similar and cover the input shaft lightly (and i do mean lightly you dont want grease on your clutch plate) and remove the shifter if you havent already this is also makes replacing the oil easier. Then position the gearbox on your jacks ready to slide on, if you still have the engine jacked up at the front this will make things easier. Take your time and guide the gearbox on watch the back of the engine and bell housing to see that its level you may need to turn the engine over slightly to move the flywheel so the input shaft slots into the grooves in the clutch once you get that far hopefully the clutch alignment tool paid off and it goes straight on and into the spigot bearing.

    * While the gearbox is still on the jacks and sitting fairly flush with the back of the engine insert your bell housing bolts and hand tighten to get the box on perfect then half bolt up the cross member so its can still move backward and forward then remove the jacks.

    * Now torque up the bellhousing bolts to spec 47 ft pound or 64 nm using 17mm socket

    * Position the starter motor and by hand put the 2 14mm bolts in and then tighten with spanner/socket

    * Next install the clutch slave cylinder, you will need to undo the bleed valve about quarter of a turn so you can push the end in to bolt up and sit behind the selector fork. There are 2 x 14mm bolts holding this on, next bleed the clutch using your home brand setup.

    * Place the rubber hose over the nipple and put a bit of fresh brake fluid into the bottle just to cover the end of the hose and top up the reservoir get a mate to pump the pedal a few times until the reservoir reaches the low indicator and top up, repeat these steps until there is only clean fluid coming from the slave cylinder. make sure the pedal is fully depressed tighten the bleed valve and check pedal and top up reservoir if needed.

    * Next get back under the car attach your tailshaft (remember you need the front half from a manual tailshaft as the auto one is too short) slide it gently into the back of the box then bolt the middle section up 2x 14mm but dont do them up tight until you have the tailshaft bolted tight onto the diff as it might need to move a bit. Once you have attached the tailshaft to the diff do up the centre piece of the diff and attach the exhaust.

    * Now there should be 2 plugs on the W58 one for the Speedo and one for the reverse light, There will be a 4 prong round white plug you need to join the white and blue to bypass the neutral starter switch and attach the black to the reverse light switch (still having problems with getting the reverse light to work will update when figured out)

    * The Speedo sender will have to come off your A340E auto box and replace the W58 sender then plug in.

    * Double check all your bolts and supports make sure everything looks ok and is done up and nothing is hanging where it shouldnt be and no tools sitting where they shouldn't be, make sure the sump plug on the box is done up tight.

    * Drop the car off the jacks and jump inside, using a funnel, cut in half bottle whatever your prefer and pour 2.4 litres of gear oil down the shifter hole you will need 75w-90w or 80w-90w gear oil, I used Penrite stuff but if you don't have a budget get some redline stuff I hear it's the goods or chuck in some nulon shift conditioner i found this helps too.

    * Install your shifter and shifter boot.

    * Now for the best part start her up and do some skids
    Last edited by VasH; 16-06-2010, 05:33 AM. Reason: weird chars from typing out in word first

  • Fabrizio
    guys one q, does lhd pedals form mk3 work? ples, would the gx71 front driveshaft work with my gz20 back end for the w58? thanks

    by the way, thank you! this post guided me perfectly through my conversion :]
    and i used the rhd pedals form a supra, bought em through yaj
    Last edited by Fabrizio; 11-07-2017, 08:41 AM.

    Leave a comment:

  • hopjis
    thanks a lot .Nice write up .This thread is so helpful . You guide us so well.Hats off to you man . It gonna help me a lot

    Leave a comment:

  • Z2TT
    JZA70 pedal set should bolt up.

    Leave a comment:

  • CdnAerocabin
    Old thread, but good info. For me in Canada, will the JZA70 clutch pedal assy bolt up or do I need an MZ20 unit? My research shows them as different part numbers, b
    ut sometimes that can be a minor difference.

    Leave a comment:

  • douglasamills
    does the pedal have a return spring?

    Leave a comment:

  • Guest's Avatar
    Guest replied
    sorry for thread revival but isnt any recent topics on this, in process of doing this conversion, clutch pedal goes to floor but wont return it just says on floor any ideas? also now when car is running it sits on 2,000 rpm and wants to stall when reved.... help

    Leave a comment:

  • VasH
    yea the stuff i didnt list is written in the procedure somewhere. i updated it anyway


    pics would be awesome too i was meaning to get some but i was on a time limit couldnt stop to take pics

    Leave a comment:

  • Axis Monkey
    ok guys, im doing my conversion tonight.

    VasH, you have a good list of things you will need however, i didnt find it detailed enough :O

    Currently the parts i needed to source were as follows.

    Flywheel bolts to hold the clutch to the flywheel face X6 (high tensile)
    Clutch pedal
    Clutch master cylinder (A70 supra)
    slave (MA61 supra) (now with your slave cylinder, usually there is a small metal rod that goes from the anodised seat in the slave to the clutch fork. new slaves do not come with this and it needs to be sourced from toyota direct as a genuine part. fortunatly, they are kept in sydney and dont need to be brought in from Japan)
    Clutch fork (should come with your bellhousing)
    Gearbox (w55,57,58)
    Clutch Line for between slave and master (got mine made up outta braid, $120 bucks, make it about 1 metre long)
    Throwout bearing
    spigot bearing
    alignment tool

    This is the detailed list of what you will need, if i have forgotten anything ill fix it up.

    Ill post up some pics of the conversion as its getting photographed for a local forum.

    Leave a comment:

  • pandaah
    +1 for braided line, its cheap, effective and will last along longer, just secure it properly cos braided line has a habit of chewing thru things if not tied down properly

    Leave a comment:

  • Looonie
    Cylinders usually don't come with a line.

    The rubber line off the slave is a seperate part you can buy.

    The clutch hardline is probably quite expensive and I would imagine bulky as you can't really bend it. Easier to just get about a metre length of braided line made up to go from the master to the slave...

    Leave a comment:

  • VasH
    thats a good question im not sure, you would have to ask your parts supplier

    i bought my kit complete with everything off another car.

    Leave a comment:

  • Axis Monkey
    Quick Question on this on Vash, does the master cylinder come with a line that goes to the slave cylinder, or do you have to source this seperatly. im buying a brand new MA70 Master and a ma61 slave, will they come with the line?

    Leave a comment:

  • GZ20SA
    this thread is wikid, its gonna help me heaps thanks man great job

    Leave a comment:

  • VasH
    updated re-worded some of the steps

    still trying to suss out the reverse light issue

    Leave a comment: