How to: R&R a T5 Manual Gearbox - V8

[Reaper]

I've done this a few times lately and have found a few tricks along the way that makes the whole thing a ton easier. You can cut some corners but in the long run they usually cost more time (trust me I have tried all of them!)

Ok - my car is a VP 5 Litre with Pacemaker extractors. Some other extractors may not be a problem but most will be in the way.

Before the car is lifted, Number the plug leads and remove them from the plugs and sit them on the injectors out of the way. Remove the plugs and then unscrew the outer most extractor bolts (11mm metric) 1/2 way. Undo the 6 bolts inbetween. The extractors will be just hanging on the outer bolts now.

Next get a 9/16 open ender/ring spaner and reach down the rear of the block about 12" above the starter motor. There is a gearbox bolt here - undo it now (once it is cracked you should be able to undo it by hand). Also unplug the 02 sensor from the loom which is in this area.

Go inside the car and unscrew the shifter knob and then unclip the surround from the centre console. Remove the rubber boot under it and the bolts for the shifter can be seen. Undo the 2 you can get to. Don't worry about the rest we will come back to them later.

Raise the car as high as you can get it. I have 4 axle stands from supercrap which do the job nicely.

Once the car is in the air, undo the gearbox drain plug and drain all the oil into a container (there will probably be just over 2 liters). Get a 7/8" open ender spanner and unscrew the 02 sensor (l/h side on the bottom of the extractor) and put it somewhere safe. Unbolt the "Y" pipe and remove it. Also remove the l/h extractor. The r/h is fine just dangling there.

Grab a 19mm spanner and socket and undo the 2 bolts that hold the steering rack in place (spanner on the nuts to the top). Don't forget to undo the steering column (12/13mm from memory). Pull the rack off it's mounting and just let it hang there.

Move to the back of the car and undo the tailshaft bolts (16mm). You just need to undo the nuts and hold the bolt against the diff flange with your finger. Once they are cracked they undo pretty easy. I replaced the nuts with 17mm (same thread though) as I didn't have a spanner that fitted it correctly and they get rounded off easily.

Undo the tailshaft in the centre (2 x 1/2" bolts) and slide the whole thing out. Move to the back of the box and unplug the reverse light wires (two plugs on the l/h side of the box) and the speedo thing (white plug on the r/h side). Remove the rear loop thing just below the back of the box (4 x 1/2" bolts).
Unwind the clutch cable adjuster and remove the cable from the fork.

Place a jack under the box to take it's weight and undo the cross member bolts that go into the chassis (19/32" socket). Slowly let the jack down a bit so the back of the box is lowered. This doesn't do your engine mounts much good so try to keep it to a minimum time wise.

Jump back into the cabin and undo the last of the shifter bolts (12mm?) and pull the ****er straight up. The plate and all comes up.

Move down under the car again with every extension you can find. (I use 3 x 12") and a 9/16 socket + ratchet. Undo the bell housing bolts you can easily get to using one extension. I have found the easiest way to get the 4 top bolts is to lay 3 exensions along the top of the box and crack them from the back of the box. Once they are started you should be able to undo them with your fingers easy enough.

Now how strong are you? I just lay under the box with my strong arm to the front of the car. With my left (weaker arm) I wiggle the box of the dowles and bench press it onto my chest. You may need to twist it clockwise (looking from the front of the car) to get the clutch cable support casting around the r/h extractor. From there I sort of twist myself from under the box and slide it onto the ground.

Putting it back in is similar but there are some tricks that I'll post tomorrow. Hope this helps somebody.

Reaper

[immortality]

nice one reaper. i've discovered similar things. those chassis stands must be nice and tall cause i find that the ones i have aren't high enough. i normaly lay under the car under the box, then lift my gut up to the box and use my body as the jack. fortunatly for the V6 i don't drop the header or steering rack. i also had a nice thin piece of wood that i use to place between the sump and the rear of the cross member to take some of the load (lost it unfortunatly but i must make another)

[Reaper]

Originally Posted by immortality

nice one reaper. i've discovered similar things. those chassis stands must be nice and tall cause i find that the ones i have aren't high enough. i normaly lay under the car under the box, then lift my gut up to the box and use my body as the jack. fortunatly for the V6 i don't drop the header or steering rack

Yeah - it depends a lot on the shape of your extractors. I can actually get it out ok with the rack in place but it is a bitch and a half to put back in. My extractor flanges are just too far back to get it in or out and removing the l/h one is easy. From memory we got stig's v6 one in and out ok without removing the rack or header. The most important thing is cracking the bolt above the starter motor - looks easy from underneith till you try to get a spanner on it - the floor and bell housing is always in the way. From up top its dead easy.

Reaper

[Morton]

Reaper, you are a god I'll be using some of those tricks next time I rip my box out.

The best tip in there, is removing the shifter housing plate and the entire shifter with it. One of the biggest challenges I faced, was attempting to line up the gearbox with the clutch assembly, with the damn shifter stick hitting the top of the trans tunnel

I, too, had to remove the LHS extractor. My Genie Try-Ys stick miles out I think the only difference between our method, aside from you removing the shifter assembly which is a GREAT idea, is that I remove all the bellhousing bolts from ontop of the motor Only needs a 14mm spanner, no extensions!

I think with some of the tips you've got in there, plus the experience I've already got, my next gearbox R/R should be down to a couple of hours

Page bookmarked and saved, and rep left. Thankyou

[Reaper]

Originally Posted by Morton

Reaper, you are a god I'll be using some of those tricks next time I rip my box out.

The best tip in there, is removing the shifter housing plate and the entire shifter with it. One of the biggest challenges I faced, was attempting to line up the gearbox with the clutch assembly, with the damn shifter stick hitting the top of the trans tunnel

I, too, had to remove the LHS extractor. My Genie Try-Ys stick miles out I think the only difference between our method, aside from you removing the shifter assembly which is a GREAT idea, is that I remove all the bellhousing bolts from ontop of the motor Only needs a 14mm spanner, no extensions!

I think with some of the tips you've got in there, plus the experience I've already got, my next gearbox R/R should be down to a couple of hours

Page bookmarked and saved, and rep left. Thankyou

Yeah - that is a different way of doing it. It works very well on the v6 but the dizzy and firewall makes things difficult from the top of the V8. Extensions from the back of the box makes it a 2 min job instead of the best part of an hour.

Reaper

[thestig]

Originally Posted by Reaper

Yeah - that is a different way of doing it. It works very well on the v6 but the dizzy and firewall makes things difficult from the top of the V8. Extensions from the back of the box makes it a 2 min job instead of the best part of an hour.

Reaper

What you really mean to say is that you can't use a rattle gun from up top. But you can from underneath. :P

L8r

[Reaper]

Now - I assume you have got the thing sitting on the ground ready to go after replacing your clutch or throw out bearing (for the third time) etc.

Firstly poke your head under the tranny tunnel and have a look at the back of the motor. You will notice there is a large(ish) hole formed with the fingers of the pressure plate and a smaller hole which the input shaft passes thru. It is *very* important that these holes are concentric otherwise you will be pushing **** up hill to get the box in.

Make sure that the bell housing is clean - give the input shaft a wipe and put a smear of grease (only a very small amount) on the input shaft where the throw out bearing moves backwards and forwards. Also put the smallest smear on the end bit that moves into the spigot bearing (I put a smear on the spigot bearing too).

Make sure you have the bellhousing bolts handy up near the front cross member within easy reach and start to think strong.

The next bit is easiest done with a friend although I have managed myself. With one at the front and one at the back, lift the box up and push the bell housing towards where it is supposed to go. I usually have to rotate it slightly clockwise (looking from the front) and then back again to get the clutch fork casting over the r/h extractor. What the aim is to get the input shaft into the larger hole from the clutch fingers and lift the whole thing slightly higher than it needs to go. From there try to slide it down (easy) while sliding it forward. When you get it right the whole thing slides into place quite easily. Most of the work till now is done by the person at the front. Once it is part in, the person on the rear tries to "walk" the box home by moving the rear up and down a bit as it slides in.

Once you are there grab a bell housing bolt and shove it in any hole handy. It should start easily with your fingers. Don't pull the box up to the block with the bolts - if there is anything more than minor resistance then something is not aligned and you risk cracking the bell housing.

Next, run around and do up all of the bolts save the one 8" above the starter motor. If you can put it in and do it up by hand then great - do it now. If it is too awkward then do it last just before you bolt up the extractor. Either way, nip it up at that stage.

Next, shove the tail shaft into the back of the back of the box (don't bother attaching anything else at this stage). Don't bother putting it over the top of the handbrake cable as the geometry doesn't work out very well. Jack up the box so it is nearly touching the top of the tunnel. Grab the oil you drained out of it (or get new oil if it is old or discolored) and pour it into the shifter hole (slowly) from inside the car.

Now for some controversy..... Holden recommend auto tranny fluid (apparently) however I recommend Valvoline 75-85 gear oil. They have a slightly heavier one too but that is too thick. This is from several gearbox specialists. The reasoning is the ATF burns up the syncros too quickly. I've run the Valvoline stuff and so far so good (9 months). Either way 2.2 litres is how much you should put in.

After the oil is in then lower the box into it's "down" position. Leave the tailshaft in place!!!!! and re-install the shifter. Make sure the ball at the base goes into it's socket. There is a plastic bush that wears and if thats so, now is a good time to replace it. Once the shifter is in place then climb under the car, jack the box up (again!) and fit the rear cross member.

From there, have a rag handy and slip the tailshaft from the back of the box, put the rag over the hole and quickly put the tailshaft over the handbrake cable and back into the box. Do it right and there will be only a drop or two of oil that comes out.

From here it's pretty much a revers of the removal process as follows:

Bolt up tailshaft, Rear crossmember (at rear of the box), plug in reverse lights (left of the box), Speedo (white plug on the rhs of the box), extractors, steering rack (make sure the wheels are pointing the same direction as the steering wheel), exhaust Y piece, plugs, leads, clutch cable, start the car and check for exhaust leaks etc. All being well you can drop the car and go crusin .

Reaper

[Morton]

Excellently written, Reaper Brilliant guide.

If I can just add, and emphasise the importance of bolting the bellhousing up IMMEDIATELY after the transmission is in place. Do NOT at any point let the transmission rest by itself once you have the input shaft through the clutch. This will damage the input shaft bearing, and possibly the clutch itself.

While trying to get the trans that final few inches into the pilot bearing, always check that the bottom AND top of the bellhousing are an equal distance from the back of the motor, aswell as both sides, which will indicate that everything is lined up straight. If this is not exactly so, chances are there is a lot of weight being held by the clutch and the input shaft