
Need Help Converting Dual-Range to Full-Range
Need Help Converting Dual-Range to Full-Range

- El_Freddo
- Master Member
- Posts: 12626
- Joined: Tue Oct 04, 2005 10:00 am
- Location: Bridgewater Vic
- Contact:
Hey Bunyip.
I have to first ask what is your motive to move to hi range All Wheel Drive (AWD)? If for street work, you won't need the diff lock.
The Hi/lo range (aka dual range) box is front wheel drive until you select 4WD or Low 4WD in the L-series.
The Diff lock you refer to with the AWD box does the same thing as selecting 4WD. Only difference is you have all four wheels with power while driving around without the diff lock on as opposed to driving around in front wheel drive mode (4WD box).
You can get an AWD box with hi and lo range for the L series, but anyone will tell you that they are few and far between, usually going for around 600 for a used box.
The other option would be to find a liberty box with the hi/lo range. These will all have AWD if its from a wagon (sedans were optional AWD if my memory serves me well).
This will require an adapter plate to mount to the EA82 (standard L-series) engine, there's one available in the for sale section (EJ engine to EA gearbox, you should beable to do the reverse -> EA82 to EJ gearbox). You will also need to find out if the gearbox diff is the same as the rear standard diff, otherwise you'll need the matching rear diff too.
Someone will beable to correct me, but i think the gearbox cross-member will need to be modified or a new one made. The CV joints are a different spline i think. And the gear shifter will need to be modified.
It would probabily be easier to go the EJ engine and gearbox swap all at once, just need to splice in the EJxx wiring loom.
I'm sure there is someone else out there who will know more than me, acutally i'd put money on that.
Also check out the Tech manual, its at the bottom of Forums menu. Its been salvaged so a few images will be missing but all the text should be there.
Hope this helps you out.
I have to first ask what is your motive to move to hi range All Wheel Drive (AWD)? If for street work, you won't need the diff lock.
The Hi/lo range (aka dual range) box is front wheel drive until you select 4WD or Low 4WD in the L-series.
The Diff lock you refer to with the AWD box does the same thing as selecting 4WD. Only difference is you have all four wheels with power while driving around without the diff lock on as opposed to driving around in front wheel drive mode (4WD box).
You can get an AWD box with hi and lo range for the L series, but anyone will tell you that they are few and far between, usually going for around 600 for a used box.
The other option would be to find a liberty box with the hi/lo range. These will all have AWD if its from a wagon (sedans were optional AWD if my memory serves me well).
This will require an adapter plate to mount to the EA82 (standard L-series) engine, there's one available in the for sale section (EJ engine to EA gearbox, you should beable to do the reverse -> EA82 to EJ gearbox). You will also need to find out if the gearbox diff is the same as the rear standard diff, otherwise you'll need the matching rear diff too.
Someone will beable to correct me, but i think the gearbox cross-member will need to be modified or a new one made. The CV joints are a different spline i think. And the gear shifter will need to be modified.
It would probabily be easier to go the EJ engine and gearbox swap all at once, just need to splice in the EJxx wiring loom.
I'm sure there is someone else out there who will know more than me, acutally i'd put money on that.
Also check out the Tech manual, its at the bottom of Forums menu. Its been salvaged so a few images will be missing but all the text should be there.
Hope this helps you out.
Thanks
My motive is that i want AWD for added traction and handling in the wet. It pissed down rain in Newcastle a couple of weeksago and i put it into 4WD hi to see what would happen and the car felt more stable. I would also like the option to go offroad so the diff lock is a must. I got out of a FWD Daihatsu Clap car (applause) to get into an all wheel drive the car was unrego and i paid $1,350 for it and its pretty straight.... I hate front wheels. I have tracked down a Fullrange box it is $600 secondhand but they want to know what ratio i want so if you can recamend a ratio that would be cool to.
- Chris_Rogers
- General Member
- Posts: 1155
- Joined: Sat Dec 31, 2005 10:00 am
- Location: Brisbane
- Contact:
the AWD L box is a straight swap. you will need the vac soleniods and a switch to make it work. also the rear diif *may* be different. shafts will require turbo ends from memory.
as for traction you will end up with 3 wheels driving (assuming rear LSD) vs one with the PT box. locking it will give you a 50:50 split vs 65:35 as standard (65 front from memory.)
the boxes are getting on now and can be hard to find. locally the vortex had it but more common donors were the turbo coupes (RX2) and wagons (GT2) . they are fun in the wet
as for traction you will end up with 3 wheels driving (assuming rear LSD) vs one with the PT box. locking it will give you a 50:50 split vs 65:35 as standard (65 front from memory.)
the boxes are getting on now and can be hard to find. locally the vortex had it but more common donors were the turbo coupes (RX2) and wagons (GT2) . they are fun in the wet

corrections (sorry Chris but we've got one of these boxes apart & I retro fitted one into my 2nd car)Chris_Rogers wrote:the AWD L box is a straight swap. you will need the vac soleniods and a switch to make it work. also the rear diif *may* be different. shafts will require turbo ends from memory.
as for traction you will end up with 3 wheels driving (assuming rear LSD) vs one with the PT box. locking it will give you a 50:50 split vs 65:35 as standard (65 front from memory.)
the boxes are getting on now and can be hard to find. locally the vortex had it but more common donors were the turbo coupes (RX2) and wagons (GT2) . they are fun in the wet
You won't need turbo shafts. The only gearbox that has different splines is the part time 4wd RX turbo box, everything else shares the same inner CV
The centre diff is mechanical like an open rear diff. Therefore the torque split is 50:50 when every wheel has traction, but can change to 100:0 with no traction at one end.
Front diff ratios are normally 3.7:1 & low range 1:1.1ish, not 1:1.596 normal dual range boxes.
I have a friend with one in pieces (my old box) so we could change the low range, but its gotten out of hand & he simply wants to sell it in bits complete if anyone's interested.
Current rides:
JDM GTII Touring wagon
88 RX Turbo Full-time 4wd touring wagon project - 97 Toyota Caldina GTT (turbo 4wd WRX eater:twisted:) - Hyundai Excel Rally Car
:???:
Previous rides:
93 Legacy GT wagon - 85 RX Turbo Full time 4wd Touring Wagon - 85 GL AWD sedan
96 Toyota Caldina wagon
JDM GTII Touring wagon
88 RX Turbo Full-time 4wd touring wagon project - 97 Toyota Caldina GTT (turbo 4wd WRX eater:twisted:) - Hyundai Excel Rally Car

Previous rides:
93 Legacy GT wagon - 85 RX Turbo Full time 4wd Touring Wagon - 85 GL AWD sedan
96 Toyota Caldina wagon
oh yeah, the vacuum solenoids to run the diff lock are identical to those for the single range part-time 4wd box on the L series.
I used the gearstick from one of these (has a button in the centre) along with the wiring & vacuum lines.
I also know where there's one like this at the local wrecker if you want the rest of the parts (& can handle a blue gearstick)
I used the gearstick from one of these (has a button in the centre) along with the wiring & vacuum lines.
I also know where there's one like this at the local wrecker if you want the rest of the parts (& can handle a blue gearstick)
wagonist wrote: You won't need turbo shafts. The only gearbox that has different splines is the part time 4wd RX turbo box, everything else shares the same inner CV
Steve you sure bout this? I have a FT 4WD Dual Range version - and it definately has 25 splines. I believe all turbo boxes - Australia or foreign RXs - have 25 splines. I bought new CV cups for mine.

did anyone else see this reply from Fang?
I had bought an 85 JDM part time 4wd auto turbo halfcut. These shafts were interchanged with the ones I had on my Liberty converted AWD box (done because shafts were thicker).
These shafts then fitted onto the full time 4wd, dual range, diff lock manual.
Maybe I'd already had the bigger splines on my first box seeing as it was one that had been built by combining Liberty internals & centre diff onto an L bell housing.
But I'm pretty sure someone had told me that the auto turbos only had the same splines as the NA models.
If anyone can prove me wrong, please go ahead, I don't want to be spreading mis-information.
Anyway, when I did mine, this is what happened with my front driveshafts.Steve you sure bout this? I have a FT 4WD Dual Range version - and it definately has 25 splines. I believe all turbo boxes - Australia or foreign RXs - have 25 splines. I bought new CV cups for mine.(Originally by wagonist)---
You won't need turbo shafts. The only gearbox that has different splines is the part time 4wd RX turbo box, everything else shares the same inner CV
I had bought an 85 JDM part time 4wd auto turbo halfcut. These shafts were interchanged with the ones I had on my Liberty converted AWD box (done because shafts were thicker).
These shafts then fitted onto the full time 4wd, dual range, diff lock manual.
Maybe I'd already had the bigger splines on my first box seeing as it was one that had been built by combining Liberty internals & centre diff onto an L bell housing.
But I'm pretty sure someone had told me that the auto turbos only had the same splines as the NA models.
If anyone can prove me wrong, please go ahead, I don't want to be spreading mis-information.
Yes I got rid of that Steve - coz I thought/realised u were comparing EJ boxes to L Series boxes.
My F/T D/R L Series box is definately 25 spline.
My F/T D/R L Series box is definately 25 spline.
wagonist wrote:did anyone else see this reply from Fang?
Anyway, when I did mine, this is what happened with my front driveshafts.
I had bought an 85 JDM part time 4wd auto turbo halfcut. These shafts were interchanged with the ones I had on my Liberty converted AWD box (done because shafts were thicker).
These shafts then fitted onto the full time 4wd, dual range, diff lock manual.
Maybe I'd already had the bigger splines on my first box seeing as it was one that had been built by combining Liberty internals & centre diff onto an L bell housing.
But I'm pretty sure someone had told me that the auto turbos only had the same splines as the NA models.
If anyone can prove me wrong, please go ahead, I don't want to be spreading mis-information.

No, I was only ever talking about L boxes, but like I said, maybe the first box I had was already 25 spline due to it being a bitser, though I'm pretty sure that the stock 85 L touring wagon shafts fitted as well.
My full-time box is still accessable, I'm going to go count the splines when I next have a chance.
At least I now know I'm not completely insane:rolleyes:
My full-time box is still accessable, I'm going to go count the splines when I next have a chance.
At least I now know I'm not completely insane:rolleyes:
Mine did too, both of them.
1989 Subaru WonderBrumby II
EJ22 Dual range AWD lifted, widened and much happier now thanks very much.
1991 L Series wagon, white and perfectly normal apart from the ticking, no I think that is normal.
Jet boat..webbered EA81 with a hybrid tin dish welded and glued to it.
EJ22 Dual range AWD lifted, widened and much happier now thanks very much.
1991 L Series wagon, white and perfectly normal apart from the ticking, no I think that is normal.
Jet boat..webbered EA81 with a hybrid tin dish welded and glued to it.
Hmm never heard of a 3.9 D/R Full Time gearbox - only 3.7. I dont think it is even possible to change the final ratio in a Full Time box.
I think a single range version came out in 3.9 in Vortex/XTs in the states.
I will contradict wagonist in saying if you have 23 spline cv shafts (regular non turbo 4WD L Series box) - you will need to get Turbo CV cups - which are 25 spline.
Also - just to re-iterate what wagonist said: Be aware - as standard, these gearboxes have a low of 1.196:1 as opposed to the 1.592:1 that is in a normal L Series box. So you do losing climbing ability in low range with the Full Time Box. You can swap the low gears from a standard L Series to a Full Time box though. (Just went through this myself)
EJ boxes suffer from the same poor low ratio as standard.
I think a single range version came out in 3.9 in Vortex/XTs in the states.
I will contradict wagonist in saying if you have 23 spline cv shafts (regular non turbo 4WD L Series box) - you will need to get Turbo CV cups - which are 25 spline.
Also - just to re-iterate what wagonist said: Be aware - as standard, these gearboxes have a low of 1.196:1 as opposed to the 1.592:1 that is in a normal L Series box. So you do losing climbing ability in low range with the Full Time Box. You can swap the low gears from a standard L Series to a Full Time box though. (Just went through this myself)
EJ boxes suffer from the same poor low ratio as standard.

No, my half cut came with a P/T auto, which I promptly ripped out & never used again (though it seems it was a 3 speed with Overdrive)Fang wrote:You are talking about an auto Full Time Box Steve??
I have no idea how many splines auto versions have. But as far as I am aware - all manual RX L Series boxes - Full Time or Part Time - are 25 spline.
I've neer heard of a 3.9 diffed version, only 3.7, though a mate has a 3.9 in the rear of his single range full time 4wd Vortex, so there is a slim possiblility.
Yeah, go with everyone else spline count, until I can count those on my old box for myself, I'm not sure what I've had now.Fang wrote: I will contradict wagonist in saying if you have 23 spline cv shafts (regular non turbo 4WD L Series box) - you will need to get Turbo CV cups - which are 25 spline.
Also - just to re-iterate what wagonist said: Be aware - as standard, these gearboxes have a low of 1.196:1 as opposed to the 1.592:1 that is in a normal L Series box. So you do losing climbing ability in low range with the Full Time Box. You can swap the low gears from a standard L Series to a Full Time box though. (Just went through this myself)
EJ boxes suffer from the same poor low ratio as standard.
If you are running a non turbo motor, you will need to change the low range. I found with a turbo motor I could get away with the crappier version, but you need big commitment & a lot of revs.
Early Impreza sportswagons had the 1:1.596 low range & maybe Foresters (but I can't confirm this), but all Liberties are the worse one.