Notice: We request that you don't just set up a new account at this time if you are a previous user.
If you used to be one of our moderators, please feel free to reach out to Chris via the facebook Outerlimits4x4 group and he will get you set back up with access should he need you.
Recovery:If you cannot access your old email address and don't remember your password, please click here to log a change of email address so you can do a password reset.

Auto Lockers. Front Vs Rear. Suiting driving styles?

Tech Talk for Suzuki owners.

Moderators: lay80n, sierrajim

Post Reply
Master of my own domain
Posts: 1516
Joined: Mon Apr 21, 2008 8:01 pm
Location: Shellharbour, NSW

Auto Lockers. Front Vs Rear. Suiting driving styles?

Post by mike_nofx »

Hey all. I know the whole front Vs rear lockers issue has been discussed/debated before but want to still clear up a few things. Also, im posting this in "Suzuki tech" because i want answers based on short wheel based, light and low powered vehicles.

1) Ive heard you need to suit your driving style to a rear auto locker. What exactly is involved in 'suiting' your driving style, Both On and Off-road?

Apparently, the shorter the wheel base, the worse a rear auto is on-road. They dont come much shorter than a Sierra, so how bad is it?

Is cornering effected, in wet and dry weather? What are they like in u-turns, or tight parking? are they safe at high speed (but legal high speed) bends?

I have been in a rear auto-locked hilux which very easily drifted around wet corners, not always intentionally. Is this normal, or possibly a bad install?

2) With a front auto locker, some peoples feedback seems to be that its almost un-noticable, while others say you need arms like tree-trunks to turn corners (or is that just what the air-locker boys say?)

Again, being such a swb, does this make a front auto any better or worse than a rear?

How is turning circle affected?

3) Do auto-lockers place increased strain on drive-line? If so, would this make the rear a better option, as there is less stuff to break?

4) Does tyre size, and tread-pattern make any difference in front/rear selection? eg. If 33" plus then front is not reccomended (in the case of a sierra)? In my case, i have 33" Silverstone xtremes (really closer to a 32") which have excellent grip off-road. but on-road probably less grip than a HT or AT.

Im probably leaning more towards a Rear auto-locker. My main reasons are that i dont want steering to be effected. Im not too fussed that on-road performance may be compromised, its not a tourer but i still want it to be safe (such as around a round-a-bout in the wet?)


Im also looking for peoples opinions who have tried front/rear/both auto-locked vehicles, and their opinions.

Not at all interested in air-lockers, and only because of the cost. For the cost of 1 air locker set-up, i can auto-lock all 4 diffs in both my 4x4's. So please, give info on auto only.

Thanks in advance
Mike
Posts: 220
Joined: Fri Nov 29, 2002 11:13 pm
Location: Canberra

Post by mattc »

I have a TJ wrangler with front and rear detroits....

On road driving (dry) style (2wd).....you need to be smoother getting on and off the gas around corners. My detroits could best be described as clunky compared to an open diff or LSD. Smoother driving = less clunks. Very occasionally, the rear locker will unlock with a big clunk. You can feel the rear of the jeep move and you can definitely hear it. Not sure about all mechanical lockers but the normal state for a detroit is locked and they unlock for corners (the outside wheel is allowed to over spin where as the inner wheel is the one which remains driven). On a grippy surface, there is virtually no impact on cornering, parking etc because the tyres have enough grip to easily unlock the diff. High speed is fine to me.

On road (wet), as you have found out in the hilux it is easy to break the rear away. Just give it a bit of gas around a corner, the inner driven wheel starts to spin, the locker does it job and locks up again = same as a welded rear or spool. Can happen just pulling away turning if the road is really slippery or too much right foot. In the wet, I find it less of a concern the faster you are travelling as 4th, 5th gears doesn't put as much torque down, harder to spin a wheel, harder to break away. In the wet, I am much more careful in slow speed turns than when travelling at 80.

Front locker - on road. Well in 2wd the front locker is basically invisible as its not driven.

Front locker - off road. One area where it is a pain is high speed dirt roads - as in say 60km/h or above. Coming into a corner, the front diff won't unlock straight away (not enough tyre grip) and my jeep will push annoyingly wide...and when it does unlock I suddenly get lots of steering as I have tended to keep turning in more and more until it unlocks. Basically, I stay in 2wd a lot more. In slow speed stuff however, I think dual detroits are great - no thinking required by me to turn on/off :) I have been told (and expect it is true) that in really muddy conditions the front won't unlock easily and a resultant reduction in steering. However around Canberra it is mostly rocky and doesn't rain much anyway ;) I have thought about converting my transfer shifter to allow 2-lo for that scenario but it hasn't been that much of a problem (ever) that I have gone to the effort or $.

I haven't broken anything in the driveline so I have no idea if it is better or worse. Mud has done the most damage to my driveline (seals) ;)

My 2c

cheers
Matt
Last edited by mattc on Mon Dec 01, 2008 12:21 am, edited 1 time in total.
Posts: 5714
Joined: Fri Nov 22, 2002 3:55 pm
Location: Perth WA.

Post by nicbeer »

ok i can answer sort of :)

I got front auto locker and rear welded (basically rear locked) (front is a powertrax locker)

1)
cornering in dry no difference unless turn is tight or sharp then i get rear wheel skip/hop. esp in shiny (carparks, servos) will chirp.

Wet : drift / oversteer city, on my 31 mudders feels like floaters, can drift out of roundabouts no Q. i usually have to trail throttle into them and then ever so lightly accelerate, (1.6 efi as well)

2)
tree trunks in mine, it does unlock but do not feel it. when in 4wd on a hard packed surface (ie gravel, limestone) its mega heavy. on sand or such then i dont really notice it but it is heavyier than std for sure.

turning circle not noticed in mine as didnt drive it for 9m doing buildup.

3) not sure but i have blown a couple unis in rear and nothing in front yet and im not the lightest on the foot driver in the slippery mud traks.

4) no idea, i got 31 mudders and have sfa grip on wet road.

ta
[url=http://www.outerlimits4x4.com/viewtopic.php?p=930942#930942&highlight=]Zook[/url]
U SUK Zook Built and Sold.
New rig is 97 80 DX. 2" list 33s
Posts: 7345
Joined: Wed Jun 02, 2004 3:29 pm
Location: Melbourne

Post by Gwagensteve »

Yay outers :armsup: a researched, well crafted question and two excellent replies!

I've not owned a car with an auto locker but I have been in and driven a few. The comments made by mattc and nicbeer are right on the money AFAIK.

my only point would be that you need to clarify what you mean by "safe" on road.

Can an auto locker be a bit unpredictable? Yes.
Will it make the car drift on a low traction surface? Yes.
Do you have to change your driving style to suit? Yes.

Additionally, because of the short wheelbase/slow steering of the sierra, you'll have to be VERY quick to catch it.

Personally, my LWB sierra runs spooled rear and airlocker front. I have all the of handling traits of a auto locker in the rear, but it's 100% predicatable.

Steve.
[quote="greg"] some say he is a man without happy dreams, or that he sees silver linings on clouds and wonders why they are not platinum... all we know, is he's called the stevie.[/quote]
God Of Emo
Posts: 7350
Joined: Sun Aug 24, 2003 7:04 pm
Location: Newy, home of the ZOOK (Rockin the 'diff)

Post by lay80n »

Having owned zooks with auto lockers for years, basically what has been said above ^^^ covers it quite well. Your best bet is to go for a drive in a auto-locked zook and see how you like it. I have had zero issue with my auto lockers. The usual breakages like axles CV's etc, but these would have broken with auto locker, welded, air locker etc.


My 2c

1) The shorter the wheel base in any car, the quicker and harsher it will transition into oversteer once rear lateral grip is lost. As an auto locker can sometimes unlock/lock violently when cornering, this combined with the already mentined WB issue can make then dangerous. The solution is to drive carefully, either coasting through tighter/slippery corners, or trailing the throttle. Whether it is locked or unlocked through the corner is not the issue (unless you drive round foot to the floor trying to spin the wheels). Trying to keep it smooth is what your want, with no sudden lock/unlocks.

2) When a locker is engaged on a hard surface the steering will always get heavier, regardless of what type of locker. Air lockers can be turned off, where as auto lockers cant. Thats basically it. Its heavy, but still managable especially with power steering. The steering weight will also depend on tyres, tyre pressure, if the wheels are bound up etc.

3) The locker does place extra stress on teh drive line, as when it unlocks under load it send a shock through the drive line. Either front or rear is pretty much the same as far as breakage.

4) Tyre size does make a differnce to the behavior of the locker. On the road a lower pressure taller tyre like a 34 LTB has larger softer side walls that take some of the "shock" out of the lockers actions. My locker is noticibly different in feel on the road between my swampers aired down and a set of cheap old near standard size tyres at road pressure.

I went auto lockers for the same reason as you, i just couldnt justify spending that much money on my zook. Having driven plenty of air locked rigs, i would love a pair of ARB's. But overall i am happy with the auto lockers.

Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
Posts: 2600
Joined: Thu Sep 27, 2007 2:40 pm
Location: Townsville

Post by GRPABT1 »

I have a rear lockright so I'll give this a go

1) I noticed it straight away going from a normal car to my zook that already had the rear locker that you have to corner different, In a straight line it's no drama. In a normal car you brake into a corner then accelerate round the apex and out. In a rear locked zook you have to roll round nearly all of the corner off the throttle then once way past the apex and with the car nearly straight again get on the throttle. The tighter and slower the turn the worse it becomes, on the highway it's not even noticable but around town you definately will. In the wet you must be careful as if it does lock it will over steer, but this is where sensibility comes into play.

2) Never driven a front auto locker but I've driven a front air locked jimny with power steering and it was only noticeable in really tight turns ie: negotiating trees.

3) I found when I did my rear wheel bearings that the splines on the axles had ever so slightly started to twist. I put this down to the locker and driving style, I don't launch it from the lights anymore after seeing that. I've seen very very twisted axles on this forum before and it has to do with tyre size, driving style, traction and lockers also play a part. Therefore yes they do add some extra strain.

4) Max tyre size before snapping axles, cv's etc would be reduce slight I would say when a locker is added, jus from the extra strain. Your tyres are basically the same as my 31" pedes so you should be right with a rear locker but I'd look at some chromo front cv/axles if you lock the front (depending on driving style again and terrain etc).

Also tyres like ours aggrevate the poor wet characteristics of of a rear locked car even more so keep that in mind. I drive very carefully in the wet but have only had a couple of minor "moments" since fitting the pedes.

Also a locker can be attributed to making a SWB easier to flip backwards in really steep hills, but driving style is more a culprit there.


That said lockers are one of the best mods any fourby could have.
Build Thread - http://www.outerlimits4x4.com/viewtopic.php?f=16&t=168546&p=1927514&hilit=GRPABT1%27s+zook#p1927514
Posts: 286
Joined: Tue May 31, 2005 11:13 pm
Location: Perth WA

Post by smileysmoke »

I just installed a lockright in the rear of my zook and i love it.most noticable thing is the constant ratcheting round corners and ppl think your zook is a shitbox about to explode.
in the wet its fun but easy to control as it doesnt just spin one tyre. offroad it rocks and you will never look back.
Posts: 696
Joined: Mon Jan 10, 2005 7:07 pm
Location: Greenbank

Post by zookimal »

I don't have many issues with mine onroad. Just have to learn when to coast and when to clutch. If anyone else drives your car it'll be them who'll have trouble. It has a lot of play in the centre though, and I'm going to rip it out and rebuild it. Has been in there for 18months.

I went from an unlocked car, to a twin auto-locked car, to only a rear auto locker. Front auto will go back in now I've rebuilt a locking centre with 26 spline side gears. I have 2low to unload the front and make turning easier, but no power steer.

Rear only is a big disappointment after having both locked. I didn't think there would be much difference due to weight transfer in a swb being over the rear wheels.

In practice, it was different. On the step up in my avatar, I found twinlocked it was an easy crawl. With rear only, it would crawl until the back end sat in the loose stuff at the bottom and a front became unweighted on the grippy stuff at the top. Front locker only, who knows, probably would have done the same thing, however it proves to me it was the front in this example that was providing the final bit of grip to keep me moving.

If I could only run one locker though, tough call. I'd run a rear locker and start saving for a front asap. I think in most of my driving the rear is more useful, but what I mentioned above is one example where a front is worth it's weight in gold.
-Mal

Zook 1, 2, 3 gone
Patrol - Wheels, engine and stuff
Posts: 835
Joined: Fri May 05, 2006 4:56 pm
Location: Sydney

Post by brendan_h »

ive got a auto locker in the rear of my zook. only got it a last month. still getting usto it.

somtimes when doing tight slow corners if you dont accelerate enough the car bunny hops and sounds like it going to stall. think its because the locker cant make its mind up wether it wants to lock or unlock causing suden lock/unlock/lock/unlock to happen and puting strain on the motor.

also notices around a few corners where it has unlocked about 50m up the road you here a big bang might be the locker locking back in?

ive also noticed in straight lines when changing gear when you get back on the throtle it wants to send the car off into the other lane. anyone eles noticed this?

haven been offroad with it yet
91 SWB Sierra. 16v 1.6efi, extractors, 6.1gears, SPOA, 32 BF muddys and 2inch bodylift
Posts: 3513
Joined: Tue Feb 15, 2005 12:52 am
Location: Perth, WA

Post by alien »

I've had a welded rear and now run an airlocker in the rear, and the airlocker blows the welded rear away by far! not only do i get to choose when it activates, but tyre wear and strain on axles is reduced greatly.

With the welded rear roundabouts and any type of corner were scary to say the least - i actually got very good at holding the back end out around corners and bringing it back in nice and slow - so much so it was just a normal thing to me, but scared my passengers... turning circle was also reduced running the welded rear, but given a few parks in a carpark that soon becomes irrelevant... long story short - you get used to it.

Now with the airlocker though i just chuck it around any corner without a drama, cos its an open diff.

If you can wait on getting an auto-locker, then save up the cash and go airlocker in the rear - the added bonus of this is a great compressor under the bonnet too.
The worst thing about censorship is ███████.
Posts: 377
Joined: Fri Jan 06, 2006 4:03 pm
Location: Perth

Post by VR Rodeo »

So long as you keep in mind that it may skip/slide when accelerating hard around corners, then you shouldn't have too many problems. As has been said just try to avoid putting your foot down until you have gone through the corner, and the only thing you should notice is the occassional loud bang /clunk.

Offroad my rear locker has a tendency to 'push' sometimes ie. if I need to turn left and I accelerate too hard, the front end can loose grip as there is nothing to help 'pull' it round.
'92 Rodeo - VR V6, T700, 31's
'89 Zook - 4 inch lift, 32's, 5.14 gears, RUF, F&R Lockrights, Rear Disconnect, Falcon/Landcruiser PS
God Of Emo
Posts: 7350
Joined: Sun Aug 24, 2003 7:04 pm
Location: Newy, home of the ZOOK (Rockin the 'diff)

Post by lay80n »

VR Rodeo wrote:So long as you keep in mind that it may skip/slide when accelerating hard around corners, then you shouldn't have too many problems. As has been said just try to avoid putting your foot down until you have gone through the corner, and the only thing you should notice is the occassional loud bang /clunk.

Offroad my rear locker has a tendency to 'push' sometimes ie. if I need to turn left and I accelerate too hard, the front end can loose grip as there is nothing to help 'pull' it round.

As the rear is locked, their is no was the inside wheel can rotate slower than the outside wheel. This is why the front end will push into understeer. If your condifent you can use throttle to initiate the turn in :twisted: Kind of like turning in with a spool in a road car :twisted:

Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
Posts: 2931
Joined: Mon Jun 21, 2004 2:43 pm
Location: Brisbane

Post by grazza »

I had a LOKKA in the front of my SWB Patrol which was great for rockcrawling.

However for touring - I remember an incident on Cape York, on very wet muddy gravel road where 4wd was basically more dangerous than 2wd. Did a complete 360 and steered into a ditch a few times. No fun.
Would be worse in a zook I imagine.
Posts: 445
Joined: Mon Feb 11, 2008 9:54 pm
Location: Perth

Post by PCRman »

Sorry officer I was just "using throttle to initiate the turn in"

GOLD! :D

You may now continue your serious discussion.
Posts: 2600
Joined: Thu Sep 27, 2007 2:40 pm
Location: Townsville

Post by GRPABT1 »

brendan_h wrote: ive also noticed in straight lines when changing gear when you get back on the throtle it wants to send the car off into the other lane. anyone eles noticed this?
I get this too, I put it down to torque steer like some FWD cars get from having two different length axles due to the pumpkin being offset. If you notice it will probably always pull to the same side, mine does.
Build Thread - http://www.outerlimits4x4.com/viewtopic.php?f=16&t=168546&p=1927514&hilit=GRPABT1%27s+zook#p1927514
God Of Emo
Posts: 7350
Joined: Sun Aug 24, 2003 7:04 pm
Location: Newy, home of the ZOOK (Rockin the 'diff)

Post by lay80n »

GRPABT1 wrote:
brendan_h wrote: ive also noticed in straight lines when changing gear when you get back on the throtle it wants to send the car off into the other lane. anyone eles noticed this?
I get this too, I put it down to torque steer like some FWD cars get from having two different length axles due to the pumpkin being offset. If you notice it will probably always pull to the same side, mine does.
As you get off the gas, the load on the diff centre from the drive shaft is reduces, allowing the centre to unlock (clutch packs to slide away from the side gears) momentarilly. As you then get back on the gas the centre locks, and the clutch packs slide back into contact with the side gears gicing drive to the axle. If one axle gets drive first (say one set of teeth engage imediatley and the other side slips over a tooth, then the drive will go to one side before being equalised. This causes the pull left or right. It is normal opperation for an auto locker type centre.

Also, keeping equal tyre pressure left to right is important, as otherwise your locker will lock in and out randomly.

Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
Master of my own domain
Posts: 1516
Joined: Mon Apr 21, 2008 8:01 pm
Location: Shellharbour, NSW

Post by mike_nofx »

wow, thanks for the very informative answers!

I think i've almost definately made my mind up on the rear end locker now.

My main concern with the front is the effect it has on steering off-road. I dont want tight turns to become a nightmare, and to lose its turning circle. The rear seems to have less off-road worries than the front, and i will put off-road worries over on-road worries any day.

As im the only one who drives my car, im sure i will get used to how it handles. I don't thrash it when i drive (although the 1.3 needs to be thrashed to do the speed limit) but i usually take it easy around sharp corners, especially in the wet, as it is.

I do have one more question regarding front auto-lockers. Once front hubs are locked in, the front diff is now locked wether you are in 2wd or 4wd. What effect does this have when driving in 2wd?

Thanks again for putting so much thought into your answers people!!

Mike
God Of Emo
Posts: 7350
Joined: Sun Aug 24, 2003 7:04 pm
Location: Newy, home of the ZOOK (Rockin the 'diff)

Post by lay80n »

mike_nofx wrote:wow, thanks for the very informative answers!

I think i've almost definately made my mind up on the rear end locker now.

My main concern with the front is the effect it has on steering off-road. I dont want tight turns to become a nightmare, and to lose its turning circle. The rear seems to have less off-road worries than the front, and i will put off-road worries over on-road worries any day.

As im the only one who drives my car, im sure i will get used to how it handles. I don't thrash it when i drive (although the 1.3 needs to be thrashed to do the speed limit) but i usually take it easy around sharp corners, especially in the wet, as it is.

I do have one more question regarding front auto-lockers. Once front hubs are locked in, the front diff is now locked wether you are in 2wd or 4wd. What effect does this have when driving in 2wd?

Thanks again for putting so much thought into your answers people!!

Mike

Steering is heavier. But because there is no load on the drive shaft, the diff can unlock much easier. Have you considered a 2-lo conversion, or twin stick. Personally i love my front locker and miss it a whole heap since its been living on the bench. Twin lock - twin stick.

If you search the net, there are some very good explenations with pictures oh how auto lockers work. Techincally they are auto unlockers.

Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
Posts: 696
Joined: Mon Jan 10, 2005 7:07 pm
Location: Greenbank

Post by zookimal »

mike_nofx wrote:My main concern with the front is the effect it has on steering off-road. I dont want tight turns to become a nightmare, and to lose its turning circle. I do have one more question regarding front auto-lockers. Once front hubs are locked in, the front diff is now locked wether you are in 2wd or 4wd. What effect does this have when driving in 2wd?

Thanks again for putting so much thought into your answers people!!

Mike
I make a point of leaving the hubs unlocked until the last minute on trips to minimise potential issues. That said, when in two wheel drive (with no torque heading to front) I find the front unlocks easily and gives me no trouble. I'm comfortable with it in the dirt but I wouldn't trust it on the freeway just in case.

Ask me again next week though, I've just rebuilt the centre so it may behave differently.

As for steering offroad, it does tighten things up, but not to the point I find it difficult. If it's a concern and the budget doesn't stretch to an ARB, consider 2low/twinsticking the case. I've found 2lo is useful for unloading the front and getting around some tight spots where low range is more useful than 4x4. When the car is in a straight line, throw it back into 4lo.
-Mal

Zook 1, 2, 3 gone
Patrol - Wheels, engine and stuff
Master of my own domain
Posts: 1516
Joined: Mon Apr 21, 2008 8:01 pm
Location: Shellharbour, NSW

Post by mike_nofx »

I haven't actually looked into 2lo conversion. So know nothing about it. I never felt i needed it, so didn't bother researching it... yet.

Although when stripping and putting back together my TC i accidentally left out the little ball which prevents 2lo. I realised when i had just finished putting it back together! When on the bench, and moving the shifter rods with a screwdriver i could actually select 2lo.

Since fitting it to the zook, ive had no dramas without the ball. Potentially i could select 2low? But im not sure how i could do it? Will look into it.

Thanks again
Mike
Posts: 286
Joined: Tue May 31, 2005 11:13 pm
Location: Perth WA

Post by smileysmoke »

hey mike this should help ya out mate: http://www.izook.com/tech/samurai/drive ... 2wdlow.htm
Posts: 220
Joined: Fri Nov 29, 2002 11:13 pm
Location: Canberra

Post by mattc »

I do have one more question regarding front auto-lockers. Once front hubs are locked in, the front diff is now locked wether you are in 2wd or 4wd. What effect does this have when driving in 2wd?
TJ Wranglers don't have free wheel front hubs so my detroit is "working" all the time. However, when in 2wd it is still virtually invisible. Maybe the steering "should" be heavier but either I can't tell or the power steering masks it.
Posts: 810
Joined: Tue Jul 08, 2008 8:40 pm
Location: vic

Post by ajsr »

ive got lockrites front and rear
I fitted the rear first and fell in love with it i dont really notice it much at all but love the traction.
the front on the other hand im less impressed with. The traction is great but the steering SUCKS im looking into power steer to help but its vaguge steering at best and I think perhaps being spring over is not helping. I find if i want more than 2wd but still want to steer you can pull one hub out 3wd but its less than ideal. I might pull the center out and play with the shims to see if this helps otherwise I forsee a air locker in my future.
but you cant go wrong with one in the rear
cheers andrew
Last edited by ajsr on Mon Dec 01, 2008 10:57 am, edited 1 time in total.
85 high roof 1.3, 6.5 tc, air lockers,ruf and 34 swampers. yep its an ugly pos.
Posts: 169
Joined: Mon Jul 14, 2008 4:20 pm
Location: CQ, Aus

Post by Zook_Fan »

considering this is one of the most detailed and properly constructed threads i have read on outers maybe it should go in the bible?
Posts: 810
Joined: Tue Jul 08, 2008 8:40 pm
Location: vic

Post by ajsr »

yeah freaky isn't it ;)
85 high roof 1.3, 6.5 tc, air lockers,ruf and 34 swampers. yep its an ugly pos.
God Of Emo
Posts: 7350
Joined: Sun Aug 24, 2003 7:04 pm
Location: Newy, home of the ZOOK (Rockin the 'diff)

Post by lay80n »

Zook_Fan wrote:considering this is one of the most detailed and properly constructed threads i have read on outers maybe it should go in the bible?

Already ahead of ya - in sierra bible labled auto locker discussion.

Layto....
[quote="v840"]Just between me and you, I actually really dig the Megatwon, but if anyone asks, I'm going to shitcan it as much as possible! :D[/quote]
Post Reply

Who is online

Users browsing this forum: No registered users and 31 guests