Potential R160 Vacuum Locker - Just one hurdle...

AndrewT · Post by **AndrewT** » Wed Dec 23, 2009 10:58 am

I don't really see why there is a need for debate. Everyone knows a locked diff is great for offroad and does bloody wonders for an L series in particular. Anyone who has actually driven one offroad will know this. These people will also know the pitfalls of driving it ON-road - it's not good at all.

As an alternative, LSD helps a bit, but is absolutely piss-poor when compared to a locked diff offroad (no matter what type it is, how hot it is, if it's "been shimmed" or whatever). Again, if you have driven both you would know. They are not designed for offroading, at all.

Yes locked diffs put extra stress on driveline, body etc etc but obviously that's a trade-off. So does offroading in general! If this was such a huge problem then ARB etc would probably have trouble selling locked diff kits.

You don't need lots of power to drive one at all. In fact it quite often results in needing to use less power to get around offroad due to the increased traction. No need to rev the crap out of your car and cain up things with wheels spinning everywhere. Just cruise up.

This thread is simply about finding a way to make it easy to engage / disengage because lets face it, it's a bastard having to slip a rear driveshaft in and out.

frogstar7055 · Post by **frogstar7055** » Wed Dec 23, 2009 11:56 am

AndrewT wrote:I don't really see why there is a need for debate. Everyone knows a locked diff is great for offroad and does bloody wonders for an L series in particular. Anyone who has actually driven one offroad will know this. These people will also know the pitfalls of driving it ON-road - it's not good at all.

As an alternative, LSD helps a bit, but is absolutely piss-poor when compared to a locked diff offroad (no matter what type it is, how hot it is, if it's "been shimmed" or whatever). Again, if you have driven both you would know. They are not designed for offroading, at all.

Yes locked diffs put extra stress on driveline, body etc etc but obviously that's a trade-off. So does offroading in general! If this was such a huge problem then ARB etc would probably have trouble selling locked diff kits.

You don't need lots of power to drive one at all. In fact it quite often results in needing to use less power to get around offroad due to the increased traction. No need to rev the crap out of your car and cain up things with wheels spinning everywhere. Just cruise up.

This thread is simply about finding a way to make it easy to engage / disengage because lets face it, it's a bastard having to slip a rear driveshaft in and out.

+1
I'd love to lock my rear diff off road but not welding because I'm not dealing with the crappy handling on road.

Well,we can dream.

daza · Post by **daza** » Wed Dec 23, 2009 4:59 pm

OK, here's my 2c.
My Subaru is my offroader, but it still has to be comfortable onroad, otherwise i'd offroad a CMV F15A Blitz!
No one's yet come up with a way to increase suspension travel noticeably that's registrable in QLD, so we're going to lift wheels.
None of the LSD types available are effective when one wheel is off the ground, so for maximum traction we want to lock the diff.
This is more important in an AWD than a part timer, as the AWD can in a worst case situation loose all drive with just one wheel in the air!
The beauty of a locking diff(as opposed to auto-locking) is that when you don't need it locked, it's a standard open diff, and so not stressing anything.

If someone's asking people about having a locking diff made, it may be better to ask about an R180, it's used in more vehicles and ARB used to make a locker for them!

Oh and if they want Half a Mil to start, the're saying "go away", politely.

Alternatively( i'll prolly get shot for this) if someone can get hold of a Hilux IFS front diff and investigate mounting and driveshaft options(for the rear of a Suby), they are available in all the ratio's Subaru used, and you can get any traction aide you want for them.

And keep the ideas coming, we've a huge knowledge base between us, we'll come up with something eventually!
Daza.

AndrewT · Post by **AndrewT** » Wed Dec 23, 2009 5:09 pm

yeah best bet I think is to find an R180 and ARB air locker secondhand to suit it (I'm sure ARB sold plenty before they got discontinued) and mount the R180 in your Suby with some clever driveshaft length mods somehow. Just the rear driveshaft length issue should be really the only stumbling block.
Just gotta get one with a ratio to suit whatever Subaru gearbox you have.
I had an R180 a little while ago in the Nissan ute I bought as a donor for my transfer case but didn't have time to pull it out before the ute was disposed of, would have been good to experiment with but oh well.

Post by **yarney** » Wed Dec 23, 2009 6:59 pm

daza wrote: Alternatively( i'll prolly get shot for this) if someone can get hold of a Hilux IFS front diff and investigate mounting and driveshaft options(for the rear of a Suby),
Daza.

What from Chugger

:twisted:

Jan

Subaman · Post by **Subaman** » Wed Dec 23, 2009 7:47 pm

The beauty of a locking diff(as opposed to auto-locking) is that when you don't need it locked, it's a standard open diff, and so not stressing anything.

Thats the beauty of a detroit, they allow the back wheels to rotate at different speeds when cornering.

daza · Post by **daza** » Wed Dec 23, 2009 8:23 pm

Subaman wrote:Thats the beauty of a detroit, they allow the back wheels to rotate at different speeds when cornering.

I've never driven one, but the descriptions i hear suggest you have to drive to suit the Detroit, they talk about having to be off the power all the through the corner so it doesn't grab mid corner? Particularly on wet or loose surfaces.

Standing on it at apex is how i normally drive(big tyres and few horses), That'd be a big leaning curve?

Daza.

YouTube · Post by **El_Freddo** » Wed Dec 23, 2009 10:31 pm

Okay now we're getting somewhere to get an understanding of why I'm/we're looking for a locker...

AndrewT wrote:...locked diffs put extra stress on driveline, body etc etc but obviously that's a trade-off. So does offroading in general! If this was such a huge problem then ARB etc would probably have trouble selling locked diff kits.

You don't need lots of power to drive one at all. In fact it quite often results in needing to use less power to get around offroad due to the increased traction. No need to rev the crap out of your car and cain up things with wheels spinning everywhere. Just cruise up.

This thread is simply about finding a way to make it easy to engage / disengage because lets face it, it's a bastard having to slip a rear driveshaft in and out.

That last bit pretty much sums it up about the bloody drive shaft issue - it also doesn't help if you have an AWD gearbox which is what I'm aiming for in the end...

daza wrote:None of the LSD types available are effective when one wheel is off the ground, so for maximum traction we want to lock the diff.
This is more important in an AWD than a part timer, as the AWD can in a worst case situation loose all drive with just one wheel in the air!
The beauty of a locking diff(as opposed to auto-locking) is that when you don't need it locked, it's a standard open diff, and so not stressing anything.

^ Bingo, this is exactly what I'm on about and why I'm not for LSDs or detroits...

daza wrote:If someone's asking people about having a locking diff made, it may be better to ask about an R180, it's used in more vehicles and ARB used to make a locker for them!

Oh and if they want Half a Mil to start, the're saying "go away", politely.

Alternatively( i'll prolly get shot for this) if someone can get hold of a Hilux IFS front diff and investigate mounting and driveshaft options(for the rear of a Suby), they are available in all the ratio's Subaru used, and you can get any traction aide you want for them.

And keep the ideas coming, we've a huge knowledge base between us, we'll come up with something eventually!

I've been looking for an R180 diff lock but havn't found anything - and as you've said ARB don't make them anymore but they apparently did so they've gotta be out there somewhere!

That half a mil is exactly that - a polite "go away"

Their acknowledgement of a locker that can be created for the R160 is what got me thinking/excited/starting this thread...

I've heard about the hilux diff being fitted to the MY for the use of a locker. I believe the first one was a modified solid axle and the second an IFS unit. I'm yet to catch up with the guy who has done this as its through a friend.

The knowledge base - I spoke to Gee this morning about it and he's given me some ideas which has been valuable information. Its just money that I don't have to do that yet - reverse engineer a hilux diff locker or something of the like, have it CRC'd (Cadd program thing) then resized to what we need, then have the components made up. All of which equals $$$s I don't have

AndrewT wrote:yeah best bet I think is to find an R180 and ARB air locker secondhand to suit it (I'm sure ARB sold plenty before they got discontinued) and mount the R180 in your Suby with some clever driveshaft length mods somehow. Just the rear driveshaft length issue should be really the only stumbling block.
Just gotta get one with a ratio to suit whatever Subaru gearbox you have.
I had an R180 a little while ago in the Nissan ute I bought as a donor for my transfer case but didn't have time to pull it out before the ute was disposed of, would have been good to experiment with but oh well.

Bugger about not keeping that R180! From what I've seen with pics on the net of the R180 diff its not any wider than an R160, only "taller" to fit the larger ring gear - correct me if I'm wrong - so that'd mean that the standard rear shafts would still fit, as would the tail shaft length wise, the inner cups may need to be changed to fit a thicker stub axle...

Subaman wrote:Thats the beauty of a detroit, they allow the back wheels to rotate at different speeds when cornering.

I'm not sure that's a "beauty" of a detroit - I'm still not sold on them behind an AWD box, I'm really only looking at this from the point of view of that odd snow trip each year - I want something that's predictable and that I can control when I want. That's my aim anyway.

For now I'm going to tear down an R160 and see what can come of it

Cheers

Bennie

AndrewT · Post by **AndrewT** » Thu Dec 24, 2009 1:46 am

One thing I did note about the R180 I had was the stubs were way different. They were more like the input flange of a diff rather than stubs. Although there are different versions of the R180 (as Disco touched on). Longnose, shortnose etc from various Datsuns etc.

discopotato03 · Post by **discopotato03** » Thu Dec 24, 2009 7:27 am

I don't know so much about Subaru apps but early Datsuns with long nose R180 diffs had companion flanges that went in the sides and were retained with a center bolt from memory .
My Bluebird only ever had a long nose R200 because thats what the DR30 Skyline semi trailing arm rear end had std . Less powerful versions of the R30 series Skylines such as the locally sold version (MR30/2.4E 1981-5) had a long nose R180 but the half shafts were retained by circlips rather than bolts , R200's use circlips as well .
Actually from memory the Aust spec 260Z's R200 had circlip retained side flanges and uni joint rear axles rather than the later pot and CV joint shafts which I think 280ZX's have .

From memory Nissan had the diff end stub axle as part of the joint where Subaru use a stub axle in the diff and a splined hole on the inner end of the DOJ . The Nissan system is good in that once the bolts are removed from the hub side flange joint you lever on the inner side of the inner joint and it slides out of the diff end circlip .
If anything the Subaru system of the roll pin is easier always provided you can compress the joints enough to get them off at least one of the stubs .
They didn't do this at the front for safety reasons I suppose .
Another plus of the Subaru system is that you can remove the DOJ's and not lose any oil because the stub shafts have the side seals running on them , not a removable Nissan style pod joint/stub axle .

I think you need someone with machining skills to sit down with a disassembled R160 and nut out ways to make a dog clutch or some other locking method for it . I'm not saying the R180 system isn't a good idea since there are some in circulation but provided it didn't lose any of its std load carrying ability an R160 would go back in with all std mounting and shafts hardware .
I wonder if its possible to drill and tap the hemisphere and one of the side gears so that some kind of pin lock mechanism could be used to prevent the differential action .
The actuation system would be the hard part particularly if you wanted in cabin selection . I dunno , if you were prepared to have another access hole in the rear cover plate (above the full oil level) you could change some locking system . It would still involve stopping/jacking one wheel cause it naturally wouldn't line up very often for fitting/removing the pin .
One thing you can't have is bits falling apart because it it got between the pinion and crownwheel it will lock the crownwheel stationary and spit you off the road - dangerous .

I just reckon solving the drive shaft and axle probs would be nearly as involved than the lock if not more so unless something factory falls in . R160's are like you know whats , everybody has one .

A .

ScubyRoo · Post by **ScubyRoo** » Thu Dec 24, 2009 11:14 am

discopotato03 wrote:
I think you need someone with machining skills to sit down with a disassembled R160 and nut out ways to make a dog clutch or some other locking method for it...

I wonder if its possible to drill and tap the hemisphere and one of the side gears so that some kind of pin lock mechanism could be used to prevent the differential action .

The actuation system would be the hard part particularly if you wanted in cabin selection . I dunno , if you were prepared to have another access hole in the rear cover plate (above the full oil level) you could change some locking system . It would still involve stopping/jacking one wheel cause it naturally wouldn't line up very often for fitting/removing the pin .

What if you used some sort of ratchet mechanism that would click in as the shaft rotated? That way you would simply need to roll forward slowly from a stand still to engage (after the actuating mechanism has been used), and maybe reverse backwards from a standstill to aid disengagement? You'd want some sort of fail safe to ensure it doesn't activate at speed or you might have a mixture of human and subi parts spread far and wide...

Maybe a cable system similar to a manual choke or handbrake that enters the diff as disco suggested, then pulls the ratchet up on a pivot (like a front derailleur of a bike) and a strong spring at the business end to pull it back and ensure it stays disengaged when not in use?

If you could work the internals so this system could work I think it could be quite effective, safe and reliable?

[rant]
This thread has been an interesting read from the start, although the comments have seemed at times more like an argument than a debate or sharing of ideas. Discopotato obviously is of the view to keep subi's stock or modified stock as well heck, the factory designs things the way they do for a reason! That we choose to screw around and modify them is a risk and challenge we take on knowingly, and that's the fun of it! I think anyone who's watched these boards for a while knows disco doesn't mean to cause offence, and his ways of looking to keep things 'stock' offer a good 'devils advocate' against the mods we get so excited about. So even if he doesn't have a lifted car, or even driven one, doesn't mean that his ideas or opinions should be chastised or ignored - he's made a lot of great posts across this board. Simply owning a DIY'd lifted subi doesn't make us the Kings of Subaru Knowledge, and closing ourselves off to other ideas makes us look stupid. Having said that, maybe he was just baiting for a reaction.... personally i reckon if you ain't got nothin nice to say, stfu fool!
[/rant]

My 2c and keep the ideas coming, at least for Bennie's sake...

brumbyrunner · Post by **brumbyrunner** » Thu Dec 24, 2009 4:35 pm

El_Freddo wrote:I've heard about the hilux diff being fitted to the MY for the use of a locker. I believe the first one was a modified solid axle and the second an IFS unit. I'm yet to catch up with the guy who has done this as its through a friend.

This "guy" used a front diff out of an IFS 'lux? That sure sounds like a tough way to go about it considering it's spinning the wrong way and has an axle tube hanging off one side.

I never did get around to it, but my plan for a selectable locker was simply to mount the rear diff from a popular, aftermarket supported IRS vehicle like a Pajero in place of the R160. Unless the splines and shafts magically match, which I doubt, just use the host diffs inner joint, the subie outer joint and get a pair of shafts made to suit. Probably do the same with the tailshaft if you couldn't swap the yolks.
All for the price of a used rear diff with driveshafts, 2 custom axles, tailshaft work, compressor if you don't have one and probably have to settle for a new airlocker.
Little bit of fab and set up the R&P.
Too easy.
What about a front locker.......now that's a challenge!
Always said I wouldn't have a go at the Malaysian Rainforest until I had both diffs locked.

Phizinza · Post by **Phizinza** » Thu Dec 24, 2009 7:59 pm

I have to apologise to start with for not reading all of the replies about the auto-lockers/detroit lockers.

I've driven a RWD 4Runner with a Powertrax Locker (same as detroit). You don't have to adjust driving style AT ALL. It drives almost like normal. And if you were only driving front wheels and had an "auto-unlocker" in the rear it would barely be obvious surely as the way they work is very un intrusive and they only lock under engine power.

An auto locker is not hard to implement and should be a lot cheaper then any other style apart from welded. I can't understand how so people who have never been in or driven a car with an auto-unlocker just dismiss them off the block. Oh well, your loss...

brumbyrunner · Post by **brumbyrunner** » Thu Dec 24, 2009 9:56 pm

I've got three vehicles with rear auto lockers, all Landcruisers, and I'm about to have one fitted to a new Hilux. My old daily driver has done 100,000kms in the last 10 years with the full blown Detroit locker and I can assure you that you have to adjust your driving style compared to an open rear diff, especially if you like to drive fast. They like to rear steer against the front steering, they cause cronic oversteer, they'll make a SWB vehicle want to swap ends......
I've never owned an air-locker (and probably never will?) but I can see the attraction to a selectable locker for those unfortunate enough to have to drive on the street everyday. Auto-lockers on the street are a PITA but I love'em and plan to put 'em in everything I drive offroad.

BTW, the Powertrax is what they call a "softlocker", similar to the Lock-Rite, Lokka and Detroits own Ezy locker. They are nowhere near as harsh in operation or as strong as a fair dinkum Detroit locker.

discopotato03 · Post by **discopotato03** » Thu Dec 24, 2009 10:54 pm

My time in a road car with a Detroit Locker was not nice , the Nismo plate LSD that replaced it was MUCH easier to live with - H190 live axle diff in case anyone was wondering .
I have driven them (lockers/No Spin) in Hino and Isuzu 4WD trucks , one an AWD Isuzu , and you can feel them wanting to push the thing straight ahead on road .
Actually quite awkward doing turns in 1st gear as one wheel wants to drive then the other as you declutch for the 1-2 change . Whole truck bucks then wants to push the front sideways with lots of driveline backlash .
Not certain but I think I was once told Detroits were developed for earth moving equipment and branched out into trucks and 4WD's .
No one who ever heard one lock under load forgets the almight crack noise they make . Effective but not really civilised those things .

I also thought about some kind of rotary spring type plunger system but its getting more complex in a confined space .
The front derallieur mechanism you speak of sounds a bit like a coupling sleeve and fork but again difficult to fit in an R160 case .

It was suggested to me earlier this evening that if enough of you were prepared to put the money up maybe someone like Modena could put something together for you . Realistically they may want a grand each and 100 sales to make it worth their while . Production runs of unique things allow economies of scale to spread the development costs over many units .
Is that sort of money acceptable to most ?

Just searching ideas , cheers A .

Phizinza · Post by **Phizinza** » Fri Dec 25, 2009 1:51 pm

Well the powertrax model in my brothers 4runner showed almost no sign of it being there. So I think maybe what you two have experienced is more down to the harsher old style detroit lockers.

And an auto locker would be completely different in the rear of an old subaru anyhow. As there is never power applied to them while on road and they will only lock when power is applied so you really shouldn't even feel it back there. You will probably hear audible clicking sound around corners but seriously that isn't much of a side effect for a locker is it>?

Oh And when I say powertrax locker I am talking about the one that looks near identical to the detroit locker, this one here > Lock-Right. Powertrax also make a softer operation locker called the No-Slip. They both lock just as much as each other which is 100% while under power.

daza · Post by **daza** » Fri Dec 25, 2009 3:17 pm

daza wrote:I've never driven one...

Actually i have, but not enough to get a feel for it, Dave M's Super Brumby.

Phizinza wrote:...And an auto locker would be completely different in the rear of an old subaru anyhow...

There are Detroits in older Subaru's and they are great, no question.
But El_Freddo and I and others i'm sure, are looking for something to suit an AWD Subaru which does more miles on bitumen than tracks.

I suggested Hilux just because they're really common and everythings available for them, Pajero's are IRS now? That would make more sense then.

If we can adapt a diff from a "real" 4WD into the back of our Suby's, then we can all pick and choose what traction aides we want!

Daza.