Jeff TT
The original 300zx specialist
Removing a 300zx auto box.
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SAFETY FIRST...BE SAFE
The fluid requires draining to minimise mess, many auto sumps have a drain however some do not, no discrimination between UK spec or import here both seem to have one with and ones without. Not all of the fluid will drain out in one go so a second drain will be required when the box is pulled off the torque convertor.
1) Before raising the vehicle, disconnect the battery, and the cable loom connectors to the gearbox, they are located towards the front of the drivers inner wing (3 x pieces) this will need to be fed down with the gearbox later.Undo do the 4 x turbo pipes from the turbos and into the throttle bodies, remove the radiators top fixings 2 x 10mm bolts.This allows the engine to tilt back later
Assuming car is now in the air via a 2 post ramp or very secure on combination of axle stands, jacks etc
2) If gearbox fitted is without a drain plug (14 mm) then remove the lower cooler pipe at the banjo fitting on the drivers side, have a large flat container to collect the fluid, one that can hold at least 10 litres, the other cooler pipe will require removal too but is higher up on the passenger side.
3) Remove the exhaust at the down pipes (14 mm nuts some times 17 mm nuts )use lots of WD40 to try and prevent studs snapping, if very tight work them back and forward till completely released.
4) Rear boxes can be removed or split just after the gearbox whatever is more convenient.
5 )Remove the combination of 10 mm nuts and bolts holding the cat shield in place and remove.
6) Mark the flanges with Tipex or some thing similar ( see why later) then undo the propshaft 4 bolts (17 mm) just behind the middle support bearing
7) Lower the rear section of the propshaft down but leave connected at the rear, now remove the support bearing bolts (2 x 17 mm) and finally withdraw the propshaft from the box, put away safely, Now there is easy access now to the gear selector above the gearbox, this has a circlip / bodypin holding it in pull that off and withdraw the cross shaft. (keep is safe)
NOTE: There are two spacers ABOVE the support bearing these MUST go back in the same place later.
(keep them safe)
8) Unclip the starter motor cable connector, undo the starter motor main feed (1 x 12 mm ) remove the starter motor cover plate (2 piece) held on with 6 x 10 mm bolts, finally remove the lower starter motor fixing bolt (1 x 14 mm) and then the upper fixing nut (1 x 14 mm) remove starter and put away safe
9) Loosen the dipstick shaft on the drivers side by removing the fixing 1 x 10 mm, higher up a cable tie requires cutting, push the assembly up, it will not come all the way out at this stage ( be aware at least 3 to 4 inches of the assembly go into the gearbox)
10) Remove 4 of the six bolts ( 14 mm) holding the gearbox rear support crossmember, and slightly loosen the remaining two ( one each side)
11) From below now undo the lower 6 fixing bolts, two are inverted ( face backwards) take the largest one and replace in one of the lower holes and tighten about half way
12) Place a jack under the rear of the gearbox, use a piece of wood as a spacer, do not jack the box up hard just support it, once this is done remove the remaining support crossmember bolts ( 14 mm)
15) A jack is now required to tilt the engine backwards so as to access the top bell housing bolts easily, a block of wood is the best and the bottom pulley the best place to jack on.
16) Once all in place, lower the rear gearbox jack slowly, the weight of the box will start to tilt the engine with it, the box will only go so far and stop.
17) Start to raise the front engine jack carefully, watching the tilt, some creaking noises will be evident as the cable loom etc. moves at the rear of the engine. Do not go too far, if the car begins to lift STOP!.
18) Now return to the dipstick (drivers side) push upwards and out of the box, pull the cable loom down from the engine bay area that was disconnected earlier.
19) Access to the top four remaining bolts (14 mm) can be made with a couple of extension bars over the top of the gearbox, be aware of an earth lead on the top left ( passenger side ) which will need refitting later.
20) Now the previously screwed in bottom bolts is holding the box in, place a the jack back under the box and take some of the weight, remove the bottom bolt, pull the box back slightly, fluid will leak from where the shaft fits into the torque convertor as it draws back, an oil tray on the floor and plenty of kitchen roll is a good idea.
21) Be aware the box is VERY HEAVY the final pull back and removal is easier with two people.
22) The box now removed needs moving away from the vehicle so access to the torque convertor can be made.
23) Torque convertor is held on with 4 x 14 mm bolts which are reverse fitted ( facing backwards) use a 14 mm spanner and a hammer to tap the spanner, turn the engine to access the next bolt, be aware that the when removing the last bolt the torque convertors tend to fall off and are VERY HEAVY and will still conatain some fluid so be ready.
If the box has had a failure ALWAYS replace the torque convertor or get it rebuilt as this WILL be contaminated.
If the box is to be out for some time remove the jack tilting the engine to relieve the pressure on the mountings etc.
Tips for refitting the box
Mainly a reverse of the removal, but watch out for the earth lead on the passenger top bellhousing bolt this is VERY important and MUST be refitted.
Be careful as the gearbox input shaft enters the torque convertor do not mash it! any damage caused here will cause problems later, an assistant will make it less likely for damage to be caused
Pre-fill the torque convertor to just below half level before fitting
Observe the markings left (with Tipex ) on the propshaft to ensure it goes together in the same place.
All cables and connectors need to be safe and secure, use new cable ties where required, Fluid replacement is via the dipstick and can be potentially messy, buy a long thin funnel, makes it much easier.
When refitting the exhaust use a small amount of exhaust paste to ensure a good seal.
As with any advise given, it is your own responsibility whether to take on this job, be safe and careful, however if you feel uneasy at all taking the job on then DO NOT try it. GET HELP.
Hope that helps
Jeff TT
.
SAFETY FIRST...BE SAFE
The fluid requires draining to minimise mess, many auto sumps have a drain however some do not, no discrimination between UK spec or import here both seem to have one with and ones without. Not all of the fluid will drain out in one go so a second drain will be required when the box is pulled off the torque convertor.
1) Before raising the vehicle, disconnect the battery, and the cable loom connectors to the gearbox, they are located towards the front of the drivers inner wing (3 x pieces) this will need to be fed down with the gearbox later.Undo do the 4 x turbo pipes from the turbos and into the throttle bodies, remove the radiators top fixings 2 x 10mm bolts.This allows the engine to tilt back later
Assuming car is now in the air via a 2 post ramp or very secure on combination of axle stands, jacks etc
2) If gearbox fitted is without a drain plug (14 mm) then remove the lower cooler pipe at the banjo fitting on the drivers side, have a large flat container to collect the fluid, one that can hold at least 10 litres, the other cooler pipe will require removal too but is higher up on the passenger side.
3) Remove the exhaust at the down pipes (14 mm nuts some times 17 mm nuts )use lots of WD40 to try and prevent studs snapping, if very tight work them back and forward till completely released.
4) Rear boxes can be removed or split just after the gearbox whatever is more convenient.
5 )Remove the combination of 10 mm nuts and bolts holding the cat shield in place and remove.
6) Mark the flanges with Tipex or some thing similar ( see why later) then undo the propshaft 4 bolts (17 mm) just behind the middle support bearing
7) Lower the rear section of the propshaft down but leave connected at the rear, now remove the support bearing bolts (2 x 17 mm) and finally withdraw the propshaft from the box, put away safely, Now there is easy access now to the gear selector above the gearbox, this has a circlip / bodypin holding it in pull that off and withdraw the cross shaft. (keep is safe)
NOTE: There are two spacers ABOVE the support bearing these MUST go back in the same place later.
(keep them safe)
8) Unclip the starter motor cable connector, undo the starter motor main feed (1 x 12 mm ) remove the starter motor cover plate (2 piece) held on with 6 x 10 mm bolts, finally remove the lower starter motor fixing bolt (1 x 14 mm) and then the upper fixing nut (1 x 14 mm) remove starter and put away safe
9) Loosen the dipstick shaft on the drivers side by removing the fixing 1 x 10 mm, higher up a cable tie requires cutting, push the assembly up, it will not come all the way out at this stage ( be aware at least 3 to 4 inches of the assembly go into the gearbox)
10) Remove 4 of the six bolts ( 14 mm) holding the gearbox rear support crossmember, and slightly loosen the remaining two ( one each side)
11) From below now undo the lower 6 fixing bolts, two are inverted ( face backwards) take the largest one and replace in one of the lower holes and tighten about half way
12) Place a jack under the rear of the gearbox, use a piece of wood as a spacer, do not jack the box up hard just support it, once this is done remove the remaining support crossmember bolts ( 14 mm)
15) A jack is now required to tilt the engine backwards so as to access the top bell housing bolts easily, a block of wood is the best and the bottom pulley the best place to jack on.
16) Once all in place, lower the rear gearbox jack slowly, the weight of the box will start to tilt the engine with it, the box will only go so far and stop.
17) Start to raise the front engine jack carefully, watching the tilt, some creaking noises will be evident as the cable loom etc. moves at the rear of the engine. Do not go too far, if the car begins to lift STOP!.
18) Now return to the dipstick (drivers side) push upwards and out of the box, pull the cable loom down from the engine bay area that was disconnected earlier.
19) Access to the top four remaining bolts (14 mm) can be made with a couple of extension bars over the top of the gearbox, be aware of an earth lead on the top left ( passenger side ) which will need refitting later.
20) Now the previously screwed in bottom bolts is holding the box in, place a the jack back under the box and take some of the weight, remove the bottom bolt, pull the box back slightly, fluid will leak from where the shaft fits into the torque convertor as it draws back, an oil tray on the floor and plenty of kitchen roll is a good idea.
21) Be aware the box is VERY HEAVY the final pull back and removal is easier with two people.
22) The box now removed needs moving away from the vehicle so access to the torque convertor can be made.
23) Torque convertor is held on with 4 x 14 mm bolts which are reverse fitted ( facing backwards) use a 14 mm spanner and a hammer to tap the spanner, turn the engine to access the next bolt, be aware that the when removing the last bolt the torque convertors tend to fall off and are VERY HEAVY and will still conatain some fluid so be ready.
If the box has had a failure ALWAYS replace the torque convertor or get it rebuilt as this WILL be contaminated.
If the box is to be out for some time remove the jack tilting the engine to relieve the pressure on the mountings etc.
Tips for refitting the box
Mainly a reverse of the removal, but watch out for the earth lead on the passenger top bellhousing bolt this is VERY important and MUST be refitted.
Be careful as the gearbox input shaft enters the torque convertor do not mash it! any damage caused here will cause problems later, an assistant will make it less likely for damage to be caused
Pre-fill the torque convertor to just below half level before fitting
Observe the markings left (with Tipex ) on the propshaft to ensure it goes together in the same place.
All cables and connectors need to be safe and secure, use new cable ties where required, Fluid replacement is via the dipstick and can be potentially messy, buy a long thin funnel, makes it much easier.
When refitting the exhaust use a small amount of exhaust paste to ensure a good seal.
As with any advise given, it is your own responsibility whether to take on this job, be safe and careful, however if you feel uneasy at all taking the job on then DO NOT try it. GET HELP.
Hope that helps
Jeff TT