1 litre tcase conversion help needed

[JrZook]

G'day all, ive just recieved a 1l tcase to replace the old 1.3l one in my '85 drover since the 1l is ment to have a lower low range ratio. But ive run into a few probs. Dunno what yr the case is but it doesnt have the 4wd switch on it.
Firstly my speedo gear doesnt fit the 1l case the helical drive doesnt match the worm gear, and the 1.3l worm gear doesnt fit n the 1l case. So i think i might be looking for a 1l helical speedo drive gear?
Secondly the 1.3l hanbrake drum/flange fits on the 1l but the 1.3 flanges dont fit. The inner diameter is too big and the 1l flanges dont match up to my driveshafts.
So far this is all ive run into at the moment.
Any help would be really apreciated, Thanks in advance, Dan

[christover1]

If its got no light, it is most likely an 83 or earlier..mines a late 83 and it has the light.
the early ones are totally different inside and out, and mount differently..not sure if mounts are interchangeable or not...you cant get any after market gears fer the early cases...I haven't heard of these issues your having with the later 1.0 Litre case into 1.3.

late 1.0 to 1.3 flanges are interchangeable, not sure if yours are.
Also on the late 1.0 and 1.3 the unis are same size, so you can use 1/2 1.0 yoke and 1/2 1.3..also not sure if yours is the same. this is how my 1.0 litre driveline connects via jackshaft to my 1.3 box.
best of luck christover

[ljxtreem]

G'day all, ive just recieved a 1l tcase to replace the old 1.3l one in my '85 drover since the 1l is ment to have a lower low range ratio. But ive run into a few probs. Dunno what yr the case is but it doesnt have the 4wd switch on it.
Firstly my speedo gear doesnt fit the 1l case the helical drive doesnt match the worm gear, and the 1.3l worm gear doesnt fit n the 1l case. So i think i might be looking for a 1l helical speedo drive gear?
Secondly the 1.3l hanbrake drum/flange fits on the 1l but the 1.3 flanges dont fit. The inner diameter is too big and the 1l flanges dont match up to my driveshafts.
So far this is all ive run into at the moment.
Any help would be really apreciated, Thanks in advance, Dan

Yep,
u have a pre 84 case, which has smaller outputts, as u may have noticed(the same size as LJ's me thinks.)
you could do some handy work with a drill to make the flanges work, but u still wont have a speedo.
best to get a new case, if its got a swich light u cant go wrong, will all fit.


best of luck




Mock

[camor]

i know this is a from a while ago, but i need to get some info...

i just picked up a pre-84 case like jrzook, but i can handle not having the speedo work. i'll just rig up a bike speedo

my question tho, is the ratios. does anyone know if the ratios in the pre-84 box are much different to the post-84 1L boxes?

i blew up some custom made rockhoppers, so had to go back to a std 1.3 trans case, but i'm running 31's, so i'm trying to get my drivablility back. 1L box seems to be the way to go.. for now

[christover1]

i know this is a from a while ago, but i need to get some info...

i just picked up a pre-84 case like jrzook, but i can handle not having the speedo work. i'll just rig up a bike speedo

my question tho, is the ratios. does anyone know if the ratios in the pre-84 box are much different to the post-84 1L boxes?

i blew up some custom made rockhoppers, so had to go back to a std 1.3 trans case, but i'm running 31's, so i'm trying to get my drivablility back. 1L box seems to be the way to go.. for now

ratios are the same with pre 83 and post 83 one litre t cases.
I'm using an early no light t-case in mine, now, ratios excellent with a 1.3, but mine has 1.0 litre driveline, so was easy to fit and speedo works fine..christover

[nicbeer]

Hey Camor,

Where in perth are you? I am running 31's with 3.9 ratios and 1ltr case. drives fine on road and off.

What did you blow up. S1 or S3

cheers

[camor]

will the flanges be a straight swap?

blew up series 3? i think? they were cut and welded gears from a combo of old an new trans cases. would do it again, but dont have the money :( i know someone who will do it tho. ends up costing much less than billet gears. trans decided to pop into 4h at 90km/h on the freeway towing a boat. i was devastated, but what can u do? still dont know why it popped out of 2h.

i live in nollamara.

[nicbeer]

oops - Most have the prob the other way around, from 4h into 2h. Sounds like a rocklobster kind of hopper.

not too sure on the flanges, may need to machine a spacer for it.

May need a air racket to loosen them also. If you need any spare WT flanges i think i have a couple at home, as mine is a NT.

Cool, me in hillarys.

thanks

Nic

[christover1]

pre 84 one litre cases have a thinner shaft, so flanges don't change over with any other cases, so I'm told.. you need a post 84 if you want to do that..or change half the uni on the jack and tail shafts to 1.o litre bits..
christover

[camor]

cheers guys. i'll see if i can swap it to a later trans.

heh the last time i took those nuts off, i needed a 6ft extension on my breaker bar, and had to make up a tool to hold the flanges be nice to have air tools....

[camor]

ok, i had a look at the other transfer cases the dude had, but there were heaps of types. came someone please make this easy? what transfer would be best to run 31's? and which model is it out of? i found one box that was in an 86 sierra ute, 1.3L engine. has the 4wd switch and looks like the shafts were similar to my transfer. but that surely wouldnt have any different ratios to mine? looks quite similar, just not as beefy.

thought this would be simple

[christover1]

I am pretty sure there is only 2 ratios of transfer case available.
early 1.0 with no 4wd light is same ratio as later 1.0 with 4wd light.
they both are roughly 12% lower than all 1.3 transfers.
1.0 litres have different bolt pattern on the flanges to 1.3 narrow tracks, and both are different to 1.3 widetrack flanges.

A 1.o litre will have a handbrake drum on the transfer.
1.3 narrows have a handbrake on the transfer.
1.3 widetracks have hand brakes on rear wheels.

you want a 1.0 litre transfer case, all other 1.3 ratios are same as what you got.

1.0 litres have the smallest bolt pattern/flange size.

1.o litres were fitted uptil about 1984 roughly.

early 1.o litres are cheapest and easier to find, but you can't just change the flanges over.

later 1.o litres have same shafts, so you can change flanges over.

all use same uni size, so you can join 1.3 to 1.0 with half and half uni yokes.

see piccy as an example, its how I connected the 1.3 gearbox and motor to my 1.0litre driveline

christover

[camor]

gotcha..

might just not have any there. will keep looking..

how do u find those shafts? any advantage over the larger ones?

[christover1]

gotcha..

might just not have any there. will keep looking..

how do u find those shafts? any advantage over the larger ones?

If you mean the input output shafts inside the t case:
I've only been using the trans case for about 6 months, which includes an Adventure Tour and a quite few harder trips, along with a lot of road driving and easier trips.
It has been great so far.
Time will tell, of course, but I think it will outlast me
But if you mean the smaller tail shafts and jackshafts of the 1.o litre driveline, not the transfer internal shafts, they have been through 9 years of hard driving, the last 4 with the 1.3 motor driving them, and they have been fine. regular servicing helps.

christover

[-ZukChiK-]

pre 84 one litre cases have a thinner shaft, so flanges don't change over with any other cases, so I'm told.. you need a post 84 if you want to do that..or change half the uni on the jack and tail shafts to 1.o litre bits..
christover

A few more Q's on this topic of driveshafts & t'cases to possibly clarify some of this info for me....

Ok, so the '85 model NT 1.3's (like JRzook's) have all the same size shafts as the 90's WT 1.3's? (ie. same diameter & not like the thin shafts found on the 82 model?) If they are the same, then its possible that I can also do the half yoke conversions with the '82 1ltr/no switch t'case I have & put it into my WT? If so then its only a matter of changing half the uni's on the jack and tail shafts to 1 litre bits , and shortening the 1.3 tail shaft to suit the length of the handbrake drum rear? Or, take the handbrake drum off completely & modify the 1.3 tailshaft to suit? Or, am I completely wrong in assuming this is at all possible & that WTs are completely different in both length & diameter of shafts & yokes than all the NTs'?

I know Ive seen info on the 2 handbrake options in another thread, but recollect it was with a post 83 1ltr (with the 4wd switch)

Anyway, how damn confusing!! In short, if its possible for me to change the yokes but not the flanges from 82 ltr case to 90 drive shafts then it may be worth keeping this case I have (currently in the for sales)

I remember Nicbeer saying it won't fit at all into a WT, which doesn't really bother me....... Just, it might ... and anything's possible in a zook innit?? !! LOL

Well, if it won't work or its too much of a hassle I'll stick to plan A & save up for a set of rockhoppers or something to go into the 1.3 trans... (and thats only if I get bigger than 30" tyres)..... if, when , maybe

[christover1]

I'm fairly sure the rear tailshaft lengths don't vary from handbrake to no handbrake Sierras. I can't see a problem with just removing the tcase hand brake, as tailshaft should still bolt up, or just leave it on, and dont use it (they are crappy handbrakes)
But I have not had much experience with WT's.
If WT unis are the same as the NT 1.3's, then it should be possible to do the half yoke thing.
My zook was a 4wd light case, and I fitted a non light case to it, my original mounts all just bolted on, so I assume WT mounts would bolt on, too.
From what I've read, speedo drive may be only problem? but surely a 1.0 litre speedo cable may be the solution, depends on the speedo end I guess.
I've had limited practical experience, but have learned a lot from sites like this, and helpin mates out, so I could easily be very wrong.
If you buy/lend the 1.0 litre bits you need, and dont permanently modify anything, then its worth trying to fit it in. If not, you,ve only lost a little (you may even get to lend the parts to try it)

good luck.
christover.

[-ZukChiK-]

Thanks Chris,

I might hold onto this t- case & muck around with the uni's then... Not having a 4wd switch doesn't worry me much, or the correct speed reading, as its always out anyway (I'll just have to confiscate our GPS & keep it in myzook!)

So, if anyone else out there can confirm that NT 1.3 & WT 1.3 uni joints are all the same size I'm all ears Will save me some time at the wreckers...

Cheers guys

[chunkz]

Sorry to dig up an old topic fellas...
just want to know if i have the early 1l t/case or the old
now i know to look for swtich and all that
but i have nfi what they look like...

I have some pictures of it... if your able to help

cheers

p.s sorry about bad quality...

[chunkz]

1 more

[christover1]

can't tell from pic, but here's a diagram, as my camera batts are dead

[chunkz]

gunna go search!!

[chunkz]

hmm its not looking good

[chunkz]

[chunkz]

shit shit shit...
dont think i have the later model one :(

any one wanna buy 1ltr t/case

[chunkz]

am i right

if this is the wrong oine... should i just ebay it?

[christover1]

It is only the wrong case if you want to put rockhopper gears, or any other make into it. The non 4wd light cases are different internaly.

If you just want the 12% reduction in hi and low, its easy enough to fit.
Well to a 1.3 NT, not sure about the WT's.
The mounts will change over ok.
And you use half a 1.0 yoke and half a 1.3nt yoke, as unis are same size, just different clips.

[christover1]

ps, I run the non 4wd light case, as I don't want/can't afford gearing kits. So I'd grab it for a spare if you decide you don't want it.

christover

[chunkz]

umm :S

all i want is the gear reduction...
and easy swap over...

[christover1]

umm :S

all i want is the gear reduction...
and easy swap over...

My favorite reason for using the older non light cases is, that nobody else wants them, that means they are easy to get, and very cheap, my last one was a freebie, to make space in a mates shed for buggy stuff.

Mines a 1.0 litre, so was easy to fit, but also I run a 1.3 motor and box, which had to be adapted to the 1.0 litre driveline.

the pic is off my 1.o jackshaft with a 1.3 g box end, just to help you understand process. same deal for tail shaft conversion, better than redrilling holes

[chunkz]

oh im just confused

So how hard will it be to have this one on my zook?

i spent a bit on it... and i dont want that money to go to waste :(

i reckon the prick could have told me
or i should have known