F-250 locking differential

[RustyCrankshaft]

Another option is the Eaton E-locker. They're a factory option on newer Super Duty's and swap into the older Sterling's with just changing the tone ring. I've found several in the yards around here for under 100 bucks. The E-lockers are pretty tuff. I have one in my trail truck in the front Dana 60 on 40's and so far I haven't hurt it.

[cleandan]

Not trying to sell truetracs but am curious why would one choose a detroit locker/grizzly locker over a truetrac.  I think of the lockers as more for dedicated offroad/rock climbing.

You'll never know a truetrac is there (no noise, no weird tire wear, no unlock scenarios), it will last longer than most trucks, and in the odd chance one tire has zero traction you can make your tire that has traction spin by feathering the parking brake...I've done that.

Jay has a good reply regarding Detroit Locker differentials. And his mention of the overblown reputation concerning Detroit Lockers and online lore is spot on... WAAAAY overblown concerning the negatives of a Detroit Locker as compared to the hundreds of thousands of miles driven using a Detroit Locker I have experienced.

I fully believe part of the overblown lore stems from many vehicle owners not being well versed in how to actually build and modify chassis and suspension parts properly so they result in various inequities they built into their off roader, hot rod, collector car, or whatever via poor design and application and mechanical work and then blame the Detroit Locker for the weird driving results.

In my post I did state the various things associated with using a Detroit locker, both from a toy vehicle use, and daily drive vehicle point of view, because I want to be as honest as I can be when making recommendations. What I did not post are some of the real life issues I have witnessed when people complain about how poorly a Detroit Locker drive... Perspective is everything here and this is something you don't get with the vast majority of online reviews, posts and comments, regardless of the literal content.

For instance, a guy I know will strongly advise against running a Detroit Locker based on his direct experience. His experience is real, but perspective matters.
What you don't know is his direct experience, while real, comes from the perspective of a 1966 Chevelle running a home built 4-link rear suspension, a 600+HP big block, a 4spd manual... and running wrinkle wall drag slicks on the street, because this was his street race toy back in the late 1980's early 1990's. That car was really fast, and it was a handful to drive on the street too.

Another guy I knew had a K20 Blazer with Detroit Lockers in the front and rear differentials, and he bitched constantly about how horribly that thing drove because of the Detroit Lockers.
What most people never knew was that K20 was running 44" tall TSL Swamper tires, using a really high lift kit, and a bunch of cheaply done modifications to get it all to fit, all coupled to a 500 HP engine and mainly used for off road screwing around... But it was licensed and insured for the road so he drove it on the road even though he should not have.

My point... when reading the reviews about Detroit Lockers you really need to understand the perspective of the writer of the review because often, they are driving a poorly executed vehicle that would have driven terrible no matter what differential was installed.

The rear tires will wear differently than a vehicle with an open differential, but that does not mean they wear out super quick. I'm still getting 50,000+ miles out of my tires when using a Detroit Locker... Unless of course the tires are very soft compound. But normal road tires last a long time without issue (I do maintain proper inflation pressures and rotate tires regularly and this has proven to maximize tire life and use over the tires treadwear range) But they do wear differently than a vehicle not using a Detroit Locker differential.

The differential does make some noise, but once you know the noise is normal it merely becomes part of the operation of a Detroit Locker with little clicks and pops here and there... It lets you know it is still working while not being intrusive.
The locker does give rise to some driving differences, most notably when traversing long, sweeping curves, but this too becomes just part of normal driving with a locker and before too long the actions are just normal routine.

The HUGE plus of a Detroit Locker is the set it and forget it aspect.
Of all the various differentials I have driven over the years NONE of them are as durable, or as consistent, as a Detroit Locker.

Install a Detroit Locker correctly, and do the required lube change maintenance, and the next time you need to mess with it will be when the carrier bearings need replacement, or you literally break the differential in some manner through hard abuse.

The Eaton True-Trac is a good Torsen style differential, and it does work well. But it is not as consistently positive, or durable, as a Detroit Locker differential.

[TJ]

Appreciate your explanation cleandan.  The one draw back I see for the detroit locker is that it's either locked or unlocked (i.e. open).  I'm guessing/assuming the locker is open during all turns.  I can understand that is fine/preferred for a lot of folks, though I wouldn't want that for the way I use them. 

In the barn yard or pasture field towing/hauling I like to have both tires pulling including while turning.  In a rare case where one tire tends to free spin with a truetrac I can temper that with the parking brake. 

My only comparison is the manual lock on 2wd tractors.  They're either locked or unlocked.  Locked is good on a long, straight pull but it has to be unlocked for turns.  Navigating turns I'll bias the differential by feathering the right or left brake as needed. 

I can see the locker and truetrac as being meant for different situations.

[pbf777]

    Utilization of the parking brake is a standard practice executed when the vehicle is solely equipped with an open-type differential.  The "idea" is that whatever enhanced turning force that is required in overcoming the resistance created in the braking force as being applied to the free-spinning wheel is also being distributed to the non-turning, better planted wheel.  And by halting the spinning wheel, provides a torque rise in the drivetrain, this creating an enhanced resistance of rotation within the differential that "might" also participate in giving the other the chance in participation.
   
    And the admission (repeatedly) that one is required to do this in order to achieve reasonable effect from the worm-geared assembly is evidence of it's unacceptability in the application.   

    Remember, the Detroit Locker is a "ratchet system", either wheel (only one) may turn faster than the ring gear, and this is the "differential" function effect; as when navigating a turn the outside wheel is allowed to accelerate ahead of the ring gears' turning rate. It's just that neither may turn slower than the ring gear.  Therefore, technically "lock-up" only takes place when one wheel begins to fall behind and is then gear-locked to the differential. 

    The ratcheting and sometimes resultant "bang" is generally experienced on hard pavement, when for example, traversing through a turn under moderate throttle, the outside wheel is unlocked ratcheting forward ahead of the ring gear, the drive torque is now being applied to the inside wheel as it is the slowest and is locked to the ring gear, and then when greater drive torque is applied in coming out of the turn, the inside wheel breaks lose (just a little) and slips forward enough to catch-up to the out side wheel, which then as the inside wheel is now the faster, the outside wheel is grabbed by the geared ratchet mechanism, the engine torque isn't great enough to maintain both wheels at the spinning/slipping speed, so you get the "clunk", maybe a little upset from the suspension and nothing more.   

     Of course, particularly with leaf spring systems there can be significant axle wrap-up that'll accentuate this; and an unknowing passenger saying what-the-F#@k!   

     Scott.

[Tommy-T]

These are fun discussions.
The 3 differentials that I personally are familiar with are the Ford Traction Lock, Lock Right lunchbox locker, and the Detroit Locker.
The Traction Lock is the only one of those that is completely invisible to the driver and they work pretty good. The only downside to a clutch style posi is that when it quits working that is invisible to the driver too...until you notice that only one tire is spinning. In reality a factory style clutch limited slip would probably be ideal for the original poster.
Since the lunchbox style lockers were mentioned I throw in my experience. Yes, having the strength of the differential rely on the cross pin of the carrier seems "iffy". I had a Lock Right front and back on our '87 Jeep YJ and did the Rubicon and most of the other major trails in the West. Never a failure although I have a Detroit in the rear end now because I switched to a 9 inch and had the Detroit on my junk pile. The front still has the original Lock Right and it works fine.
All of my FE powered hot rods have had Detroit Lockers. Mostly because you can buy used NASCAR lockers from Ebay for less than $300. The strength is legendary. My stuff is usually tubbed so the rear end gets stressed every time out. Never a failure.
I will admit that my hot rods and my Jeep would drive crappy with open differentials. The point I'm making here is that the lunchbox lockers and the NASCAR takeout lockers behave nearly identical. They click 'n clack sometimes loudly, and get weird in long sweeping turns. Without reason they will sometimes NOT unlock when going from a stand still to a right turn. That said, it's nothing so abrupt that I wouldn't allow my wife or friends to drive my cars.

[TJ]

 
   
    And the admission (repeatedly) that one is required to do this in order to achieve reasonable effect from the worm-geared assembly is evidence of it's unacceptability in the application.   

 

That's not quite what I said.  I said "...in the rare case...".  I've had one tire on wet grass and one on dry concrete.  Stomped the gas and left rubber on the concrete.

In my application (slow moving heavy loads) I prefer the seamless transition of torque to the tire with traction.  The slip and grab action of a locker doesn't sound like something I want for my application though I can understand why other applications (like racing or rock crawling) wouldn't even notice the slip/grab action.

I think the military hummers also have a torque biasing differential...like the truetrac.  So I don't think there is a one size fits all...choosing the locker or the truetrac is partly personal preference and partly different driving needs.

[Tommy-T]

 
   
    And the admission (repeatedly) that one is required to do this in order to achieve reasonable effect from the worm-geared assembly is evidence of it's unacceptability in the application.   

 

That's not quite what I said.  I said "...in the rare case...".  I've had one tire on wet grass and one on dry concrete.  Stomped the gas and left rubber on the concrete.

In my application (slow moving heavy loads) I prefer the seamless transition of torque to the tire with traction.  The slip and grab action of a locker doesn't sound like something I want for my application though I can understand why other applications (like racing or rock crawling) wouldn't even notice the slip/grab action.

I think the military hummers also have a torque biasing differential...like the truetrac.  So I don't think there is a one size fits all...choosing the locker or the truetrac is partly personal preference and partly different driving needs.

I have a couple of pals that have Truetracs in the front end of their Jeeps. They like them a lot and they seem to crawl on rock as well as my Lock Right does. They do not make the snap, crackle, pop my locker does. I believe they'd work as well in the rear end but I have no personal experience with that.

[pbf777]

      As I recall, the "Truetrac" product hit it's stride along with the 4 X 4 craze in the late '70's.  Back then "posi", "limited-slip", "trac/tion-loc, etc. (whatever!), was available from the O.E.M. for the rears, but other than for the Bronco, not for the front axles.  Then the tires got bigger, and soon something other than the clutch type differentials were necessary if one actually expected both tires to be turning, particularly in the mud!   

      For the rear Detroit Lockers were for the well-healed, for the less so, "Lincoln-Lockers" (welded) became popular; but what for the fronts?  Either of these, though truly "positive locking" and ensured that all four (4 X 4) were going to be turning in the mud, how could one ask for more.  But particularly as with the front axle, if all of the tires are "locked" together, turning exactly the same revolutions at all times, surprisingly when off-road on a lose surface, you can turn the front wheels to the left or right, but the vehicle doesn't readily change direction!   Been there dun that!   

      So here comes the Truetrac, with that "seamless" differential action that allows the tires to differential when the wheels turn left & right and it works great; but the observant operator realizes that although this product is truly superior to the otherwise "open" unit, it isn't as positive as the "locked" assemblies as it surrenders to the external environmental factors acting upon it's function.  But for the front axle this was an acceptable compromise for greater civility and was in that frame of mind that it was initially marketed.   

      Later, as the engine torque outputs have increased, and the public finds new ways to test their vehicles, you'll note that some of these worm-gear guys are now coupling "clutch-packs" to their units.  The purpose here is to provide a certain sum of "preload" to the gear-sets to aid in their functionality; something akin to the idea of applying the parking brake as mentioned previously.  Note that these are "torque bias" in operation, in other words, if one wheel is off the ground, there's a minimal torque application involved to make it turn, and therefore not so great a value being applied to the opposite side either.   

      And hence, I would think would be a 'very' poor choice for something particularly like "rock-climbing"!     

      Scott.



 

[TJ]

There's a scenario with the Detroit locker that I cannot figure.  Let's say I'm pulling a truck with trailer combo that grosses 8 ton.  I'm on a marginal traction surface...slick grass, snow, whatever..  I'm in low gear because I'm in a driveway, field, etc and both rear tires are working to keep me moving.  Now I need to make a 45 degree or more turn.  How does the outside tire increase speed so it can unlock?  And if it can unlock, how to I keep moving? 

Remember, this is with a 2wd F250...I believe that's what the OP has.