Front Mechanical Locker Experiences?

[Metcalf]

I've been running an automatic front locker ( Yukon Spartan ) and a selectable rear locker ( Ox with internal air shift ) in my flat fender for about 8 years now. It is my favorite all around combo for what I do to date. My other off road vehicle has selectable front/rear/center diff locks......I prefer the flatty combo in many ways.

 

[billiebob]

The Detroit Locker does this.

Correct me if i am wrong but the Detroit Locker only locks under acceleration, it offers not traction control when descending a steep rough grade. And they only lock if the speed differential is excessive meaning they all slip before actually locking.

The selectable locker is a spool accelerating or providing downhill braking. Auto lockers are not. And some auto lockers only lock if you stand on the brake and the gas..... ie the military H1 Hummer.... meaning you are definitely not treading lightly.

I swear by selectable lockers front and rear, especially pulling a trailer.

 

[Metcalf]

Correct me if i am wrong but the Detroit Locker only locks under acceleration, it offers not traction control when descending a steep rough grade. And they only lock if the speed differential is excessive meaning they all slip before actually locking.

The selectable locker is a spool accelerating or providing downhill braking. Auto lockers are not. And some auto lockers only lock if you stand on the brake and the gas..... ie the military H1 Hummer.... meaning you are definitely not treading lightly.

Generally all automatic lockers ( detroit, yukon, lunchbox lockers, etc.....ratchet teeth lockers ) only allow ONE tire to rotate faster than the ring gear. That is the only way they can unlock.
They do not 'slip' at all. They do not unlock or coast when going downhill. They provide plenty of downhill braking from both tires.

You are confusing some details between a 'torque-biasing' limited slip like a Tru-Trac ( like what comes in most H1 hummers ) with a true automatic locking differential like a Detroit locker.

 

[MTVR]

Most of the auto lockers must slip before engaging, or they slip and require you to apply brake and throttle.

No.

What you are describing is clutch-type differentials, not lockers...

 

[charlieaarons]

I have Lockrights at both ends on my diesel M37. Fortunately it has power steering and unlocking hubs. Caution is required with hubs locked in 4wd on ice.
Otherwise it is great.
Everything else I own with front locker is selectable.

 

[b dkw1]

FWIW, I have a trutrac LSD

Worm gear diffs are TBD's (Torque Biasing Differentials). Unless you have a Wavetrac as they have a clutch in them along with the worm gears.

Short wheelbase vehicles are a lot more sensative to front lockers types. I ran a few different types in My old Bronco.

Open, good on the street and in snow, sucked off road
Spool, ruled for crawling, sucked on the street or for normal trail driving.
Detroit, good on trails , great for crawling, did lots of funny ******** on the street.
Trutrac, excellent on the street, ice & snow, trails. OK for crawling.

Current build has a OX locker. No comments on how it works yet as I haven't driven it yet.

Wavetrac also looks promising but no options for what I am building now.

 

[another_mike]

Current build has a OX locker. No comments on how it works yet as I haven't driven it yet.

I have 3 years on mine and its been flawless.. and the fact its made in the USA means it will be the only one I buy from now on.

 

[Metcalf]

Worm gear diffs are TBD's (Torque Biasing Differentials). Unless you have a Wavetrac as they have a clutch in them along with the worm gears.

Short wheelbase vehicles are a lot more sensative to front lockers types. I ran a few different types in My old Bronco.

Open, good on the street and in snow, sucked off road
Spool, ruled for crawling, sucked on the street or for normal trail driving.
Detroit, good on trails , great for crawling, did lots of funny **** on the street.
Trutrac, excellent on the street, ice & snow, trails. OK for crawling.

Current build has a OX locker. No comments on how it works yet as I haven't driven it yet.

Wavetrac also looks promising but no options for what I am building now.

I've had my Ox locker ( rear, D44 ) for 8+ years now. It has been perfect.

To me, it seems like most of the 'bad' locker characteristics are more from the REAR locker than the front locker. With the rear diff open on my 85" wheelbase old flat fender, the front automatic locker is happy to just do its lock-unlock-lock thing automatically. Other than a little more return to center feeling under power, there are no bad traits honestly. Hit the rear locker button and everything changes. You can feel the chassis being much more bound up and fighting itself. I rarely have to use my rear locker however, I could honestly have it on a momentary switch at this point. Adding rear cutting brakes would decrease rear locker use even more.

 

[1stDeuce]

I've had my Ox locker ( rear, D44 ) for 8+ years now. It has been perfect.

To me, it seems like most of the 'bad' locker characteristics are more from the REAR locker than the front locker. With the rear diff open on my 85" wheelbase old flat fender, the front automatic locker is happy to just do its lock-unlock-lock thing automatically. Other than a little more return to center feeling under power, there are no bad traits honestly. Hit the rear locker button and everything changes. You can feel the chassis being much more bound up and fighting itself. I rarely have to use my rear locker however, I could honestly have it on a momentary switch at this point. Adding rear cutting brakes would decrease rear locker use even more.

Metcalf, I would suggest that the difference you are attributing to front vs rear is actually the difference between an automatic locker and a "selectable" locker. An "automatic" locker always allows for a wheel to over-speed without consequence, somewhat relieving driveline bind in a turn. An engaged selectable locker is, in effect, a spool. A spool adds a LOT more steering resistance than the auto locker, regardless of which end it is installed in.

My experience is that in rock crawling and other other technical low speed wheeling, when going from uphill to downhill (or drive to coast, or any other reason for torque reversal on an axle shaft), an auto locker of any kind can occasionally release and pop on one axle as torque on the axle shaft reverses. This can result in a bit of lurching of the vehicle as a bit of rotational "slop" on the diff is taken up. A spool or engaged selectable locker will not do this. Perhaps this is some of what billiebob was referring to, but I do agree that he's also still attributing "limited slip" characteristics (like being assisted by brake torque) to automatic lockers, which is incorrect as Metcalf and MTVR pointed out.

I bet the OP is bored silly with our technical discussion at this point, but hopefully it'll answer questions for others too!

 

[Metcalf]

Metcalf, I would suggest that the difference you are attributing to front vs rear is actually the difference between an automatic locker and a "selectable" locker. An "automatic" locker always allows for a wheel to over-speed without consequence, somewhat relieving driveline bind in a turn. An engaged selectable locker is, in effect, a spool. A spool adds a LOT more steering resistance than the auto locker, regardless of which end it is installed in.

My experience is that in rock crawling and other other technical low speed wheeling, when going from uphill to downhill (or drive to coast, or any other reason for torque reversal on an axle shaft), an auto locker of any kind can occasionally release and pop on one axle as torque on the axle shaft reverses. This can result in a bit of lurching of the vehicle as a bit of rotational "slop" on the diff is taken up. A spool or engaged selectable locker will not do this. Perhaps this is some of what billiebob was referring to, but I do agree that he's also still attributing "limited slip" characteristics (like being assisted by brake torque) to automatic lockers, which is incorrect as Metcalf and MTVR pointed out.

I bet the OP is bored silly with our technical discussion at this point, but hopefully it'll answer questions for others too!

My front automatic locker behaves night and day different based on the REAR axle. If the rear axle is open the front axle is happy as a clam. You can't really even tell the front is locked other than a bit more return to center feel in the steering wheel when on the power ( and I have very wide tires and wheels on the flatty that are run at 1-5psi off road ). No pops or windup at all.

With the rear diff locked ( effectively a spool as you mention ) it completely changes the characteristics of how the chassis behaves. You can tell it wants to go straight much more. It doesn't really increase steering force too much, the steering just becomes less responsive and the front tire gets folded over more as the vehicle is trying to go straight.

Personally, I think it boils down to the rear axle always wanting to go straight and the front axle wanting to go in the direction you point it. This is why I am a big proponent of 'front locker first' contrary to how most vehicles are set up. For me, that just works WAY better all around. The largest speed differential is actually on the REAR axle in a tight corner. I think the open rear diff allows the vehicle not to 'push' as much as a locked rear diff with an open front diff, especially when trying to climb and turn at the same time. I usually refer to this at the '3-wheel drive' problem. It is that odd time when you need more than open/open but less than locked/locked AND vehicle maneuverability is still very important. Going in a straight line with lockers is easy, the nuance is when you have to maneuver the vehicle when open/open is not enough. There is also some interesting stuff going on between the front and rear axle speeds in a tight corner....that adds another layer of weird.

For me, front and rear automatic lockers still have too much 'push' in 4wd. Front wheel drive only can help, but then you are back to 2wd....not 3wd.

I don't mind selectable/selectable, but for me it just doesn't work as well for what I do. I get REALLY annoyed having to lock-unlock-lock all the time when trying to tightly maneuver the vehicle when dealing with the '3-wheel drive' issue. Selectable lockers, especially in the front when dealing with scrub radius bind, don't like to unlock right away.

 

[Hillbilly Heaven]

I am giving thoughts of using an Eaton E-locket up front since I am using a Ford E-locker in the rear. I have manual hubs and never use them except in the real necessity. Having the option of the E-Locker up front does give me the option if the hubs are locked and one wheel is in the air to still pull with the front. Not concerned so much at that time about turning. Yes using the E-locker in the rear in 2wd does effect turning and can even cause tire scrub on pavement. Not a good idea but can be excellent if on a loose dirt, sand, or mud.

 

[b dkw1]

I am giving thoughts of using an Eaton E-locket up front

Be aware that they need to rotate a little to engage. They work of ramps, the rotation drives the pins in. When you reverse, they disengage and then re-engage. If you are trying to do this quickly under power it will round off or shear the pins.

 

[C p weinberger]

Let me throw in another variable...
Under hp’d engine vrs Weight, 2H Toyota in cruiser..
Touching a brake to get traction? In deep sand driving with cruiser that middle pedal is never touched or you‘re shoveling. I’ve been in many dangerous situations where your locking and driving selection is decided upon before you proceed ahead.
All things are not possible. Choose the most reliable system that will work 95% of the time, that last 5% is “unubtanium”/ financially heavy

 

[I Leak Oil]

Ahh, the age old locker debate. Filled with facts, myths, opinions passed as opinions and opinions passed as fact. Almost as good as the winch or motor oil debates.
If you had lincolns then you'll know 99% of what to expect. The other 1% is the quirks of the unit unlocking and relocking on occasion.
Really boils down to your own personal tolerance of the driving characteristics. Again, if you were welded at both ends you'll know pretty much what to expect.

 

[Buliwyf]

Detroit Lockers, and Yukon Grizz lockers, aren't lockers at all. They're unlockers. They unlock the outside tire in turns for a moment. They're locked up at all other times. The Grizz is perfect for strong front diffs. I prefer selectable rears now.

Billie, you're thinking of the G80 gov bomb, or something.

Front Grizz isn't hardly any worse than a Trutrac in snow, if your rear axle is unlocked.

The OP should also consider upgrading to freespin hubs.

Yukon Spin Free Hub Kit for our Dodge 2500 Project Bighorn – www.OFFROAD-REVIEW.com

www.offroad-review.com