Torana SS

[immortality]

I miss having a lathe at work. I wish I had room for one at home.

I'm prototyping a alternator bracket atm, I'm going to have to go to a laser or water jet cutting place to make it but I'd love it much more if I could machine it on a mill.

[vlad01]

I do have the room for a lathe. I actually want my own decent sized blasting cabinet before I'd consider a lathe and maybe a dryer and aux pressure tank so the compressor can keep up and the air is dry, but $$ which I have very little these days. But blasting is something I have done regularly as outsourced and it would pay for itself eventually. In fact I have some stuff I'm getting blasted tomorrow.

[VK_3800]

In March this year I drove down to the Caroline Bay Rock and Hop in Timaru. First time I've attended as this is roughly an 8-hour drive each way (depending on traffic and road works) but thoroughly enjoyed it. They also held a "cruise" on the Levels raceway which was a bit of fun, although hard to keep up with those supercharged late-model Mustangs and Camaros on the straight.

Had a minor issue on the way there, big rock in the middle of the road which couldn't be avoided - didn't bother the 4WD in front of me but lifted the Torana off the suspension! Couldn't see any significant damage at the time but turns out it hit the gearbox right on the joint between main case and tail housing. This was enough to create a minor deformation in the mating surface and because the TKO has tight tolerances and doesn't use gaskets that in turn caused a leak. I also had some carbon-lined synchros and brass fork pads waiting on the shelf to try out, with a few days off work I finally got around to removing the box earlier this week.

You can just see the darker half-circle area which was pushed out in the main housing, at the bottom just left of centre (already stoned flat in this photo):


Unsurprisingly the plastic fork pads had seen better days, in particular the third gear edges were completely gone. Almost like someone has been a bit rough on the shifts, surely not?! Funnily enough third gear exhibited the least problems, although fourth was starting to clunk a bit so maybe the opposite side suffers first.

However this had started wearing into the shift fork too; the new brass pads would have gone on but I wasn't confident in them staying put. The pads are supposed to be flat, that circular groove from the synchro hub doesn't belong:


Cleaned it thoroughly and added material with some careful tig welding (please ignore the horrendous mess in the background):


Then spent far too long setting it up for machining:


Much better, the new shift pads won't go anywhere now:



Spent many hours getting it back into the car, it's been so reliable for so long that I haven't needed to take anything apart and have forgotten how the jigsaw goes together! The twin plate clutch was also stubborn for some reason, it took quite some effort to get it to slide into the second hub despite having slid out just fine.

The reduction in 3-4 throw is immediately obvious (funny that). I've been taking it easy on the shifts to let the synchros bed in a little but it certainly seems better in general. There's no obvious damage to the original all-brass synchros but the friction-lined ones have a better chance of grabbing the heavy gears (this is why T5s and T56s have nice shifts). The brass pads also give a nice direct feel and no leaks so far.

[heff0018]

Any gearbox work overwhelms me so freaking amazing what you can achieve. I am installing engine rings and bearings this week so that will keep me occupied. Cheers

[VK_3800]

These are not bad actually, quite easy to work on. I did have to re-pack some needle rollers but no press required to remove gears from the cluster, just a stubborn circlip or two and it all slides apart.

[vlad01]

I've rebuilt 3 T5s so far and pulled apart many more for salvage and I find them easy now and I've come up with some of my own tricks, so I reckon I could tackle most gearboxes easily enough.

Autos are daunting to me, but since I'll probably never own one again it's a very unlikely scenario. I'd like to build a diff one day, but I do struggle to read the contact pattern with the dye they use, looks super vague to me when I look at the patterns, it's not black and white like they are in a gearbox, the hypoid gearing just smears everything out into a senseless mess.


VK_3800, interesting regarding the fork pads, out of all the T5s I've not had a single one with bad pads, most were almost like new including my first box that had 600k on it at the end and I smashed that through gears for a good 250 of those Ks. I wonder why your TKO was so bad? I always thought those bronze pads were snake oil, at least for the T5. I wouldn't have thought brass rings would make that much of a difference, the T5 have brass on 5th and 5th is a notorious gear for issues since its so far out from the center of the gate and always suffers from the shift boot pulling back on it, yet I have seen little wear on the pads but at the same time, huge wear on the dogs for the hub and gear due to the constant pulling on the stick, so naturally the pads would always be engaged from that, but they seem to not wear at any appreciable rate.

[VK_3800]

The fork shown was the only real damage over ~75,000km so it wasn't exactly bad. Comments below are just my opinion but it seems to line up with the driving experience.

As I understand it the basic issue with the TKO is the additional mass of the bigger gears, meaning the shift components have to work that much harder. In this case the pads were only damaged on the third gear side of the 3-4 fork, others were fine. I imagine the damage started as the result of a forced shift or two and as soon as the pads start deforming its all downhill from there. The brass ones are just a little more robust, possibly at the expense of a little more harshness at the stick. I seem to recall someone here having issues with third gear shift fork damage in a T5 too? But if you never encounter the issue then yeah I expect its a pointless change. Also worth noting I upgraded from the standard shifter some time after first installation, the original doesn't have any stops so there's an outside chance this damage started very early on.

Regard the full brass synchros, there didn't appear to be any significant wear or damage there. The friction synchros are just another attempt to give them a fighting chance against that additional gear mass, they work in other transmissions including the newer TKX I believe. This is more of a try-it-and-see upgrade than a fix; I'd like it to shift a little faster/easier if possible but it never missed shifts.

Before the TKO I had a Muncie which was a great box. It would shift OK during casual driving (not as smooth as a modern setup, but good enough). Where it would shine is more spirited driving, if you wanted a quick shift just hit it harder (again with stops on the shifter!) and it would never refuse to go in. The TKO certainly isn't like this, much like all these Tremec boxes it will only shift in its own time so forcing it is a bad idea, you have to wait that split second for the synchros to do their thing.

[vlad01]

ATF fluid allows the T5 to shift extremely well in most scenarios and really befits hard shifts I found, Holden putting gear oil in them was a huge mistake and made them shit for hard driving and kills the liners of the rings pretty much out of the factory. Tremec puts a big warning in their service manual against using oil as it's stated to kill the rings. The thing the Tremecs hate is heavy clutch plates, that slows the shifts up a lot and as you mentioned, you just have to wait for it to go in. The carbon rings help with higher rpm and inertia. But if you can reduce the size and weight of the plate, they shift awesome. The ceramic puck plates are the lightest in a conventional type of setup, but I understand they aren't for everyone in terms of drivabiliy. Organic is a close 2nd in lightness and cushioned ceramic is massively heavy. Smaller diameter even with similar weight reduces inertia a lot too, so simply switching to a smaller diameter can help. This is why those tiny Tilton multi plate motor sport clutches are choice for motor sport where shift speed is a must as well as load capacity, having multiple small diameter plates still had less inertia than one bigger plate and usually more load capacity to boot.

It's tricky if your build needs a good clutch which often pushed up the weight by design on the plate, the cushioned ceramic ones are by far the heaviest ones, in my mildly hot VP I have one of them and it slows the shift, I also found a short shifter to slow the shift as well as you have reduced force at the box and increased force at the hand, so they actually suck, they would only be good when using a dog box where force is very low and speed of shift is important. On a sync box I found them counter productive in a big way, so the stock shifter is what I use. The Tremec detent plate is the stop, you can't over-shift a T5, people say that, but its just a myth. Anyone who's built one will see that you physically can't over-shift them as the detent and shift lever/lug is the limiting mechanism and is built like a tank, far stronger than the stops aftermarket shifters have. What can break the forks is slamming it into gear faster than what the rings allow which is not a limit thing but a ring limitation + abuse thing.

Interestingly, in the Holden supplied rebuild kits via BTR, they say to change the 3-4 pads to the black ones over the white type. Physical dimensions are identical, so I assume it's a material change.

All factory T5s I have seen from about 94 onward have the black pads already installed on the 3-4 fork. I can't find anything in literature to what the actual change is for, other than it must be done when overhauling an older T5. The black pads are available new from Tremec, so they still do it. I didn't see it mentioned in the Tremec service manual, but it was a big warning print out in a NOS Holden T5 overhaul kit I got cheap a few years back.

I wonder if this relates to the 3rd pad issues you had in some way, even though it's a TKO and not a T5.

[heff0018]

.

Autos are daunting to me, but since I'll probably never own one again it's a very unlikely scenario. I'd like to build a diff one day,

I’ve rebuilt an auto and it wasn’t too bad with the right YouTube video, I would like to rebuild a diff also but agree it wouldn’t be as easy and people make it sound

[immortality]

Make sure you have the right range of shims before tacking the job.

I did a M80 and it was noisy because the pinion was a bit deep and I didn't have the correct shims to fix it.