Axle differential locks for full size vehicles?

[ebinmaine 67,555]

I'm considering ordering a diff lock for my 86 f250 so the rear axle would be in full posse all the time.

Wondering if anybody has any experience or comments on these one way or the other...

 

 

https://www.summitracing.com/parts/pwt-1840-lr

 

 

 

[953 nut 55,282]

19 minutes ago, ebinmaine said:

considering ordering a diff lock for my 86 f250

Planning to go drag racin with that there F250?          

I had a Chevy pick-up with factory Posi traction and when you were on slippery pavement or just got onto the throttle hard the rear end of the truck would kick out to the right. The Dodge I have now has a limited slip differential and I don't have that problem.

[ebinmaine 67,555]

20 minutes ago, 953 nut said:

Planning to go drag racin with that there F250?          

I had a Chevy pick-up with factory Posi traction and when you were on slippery pavement or just got onto the throttle hard the rear end of the truck would kick out to the right. The Dodge I have now has a limited slip differential and I don't have that problem.

Not so much with the drag racing but there will be occasional forays into the middle of nowhere. 

There are numerous places in the woods up here where there's a greasy mud hole on one side and dry gravel on the other.

It would be handy to have the main drive axle locked together on both sides.  

 

Fact is, I need to replace the carrier itself and the spider gears as well.

I figured while I was in there I might add posi traction to the equation instead of leaving it at open diff.

 

[Pullstart 62,905]

EB, I’d suggest either an air locker, e-locker or limited slip like Richard recommended.  A full spool posi is asking for trouble, until you actually need it.  It’ll chew your tires to oblivion in a quick hurry, unless that slip is available when you don’t need posi.

 

*edit* story time!

 

When I turned 16, I managed to ride out the wreck of a three wheeled Jeep Cherokee, all the way to the tree that stopped us.  It had been a salvage repaired vehicle, so it’s hard saying how bad it was before I made it my own.  Once I was vehicle shopping again, I stumbled upon a square body S10, on a Toyota frame, with a 350 Chevy, 35” bald tires and 1/2 ton solid axles.  It was perfect!  The chop shop corner greasy haired shiester dealer let me take a test drive with my 28 year old buddy.  We were in the quiet part of town at a 4 way stop and I stomped on the gas.  It spun us around about 270 degrees, all the way to the front yard of the quiet neighbor’s place.  I was too dumb and irresponsible to admit my guilt, so we just high tailed it out of there and brought the truck back to the dealer.  Crazy thing is, the signed title from whoever traded it in, was sitting in the glove box.  We were VERY tempted to simply drive it to the DMV and sign the rest of the title to ourselves.  Hindsight, I’m glad we brought it back.  I’m glad I asked my mom to come down and take a look at my new truck.  I’m glad she found the huge crack in the frame that I so overlooked!  I ended up finding a VW Jetta instead of that big ole lifted AMAZING pickup.

 

That’s not my only Lincoln Locker truck I’ve driven on the road, but it was definitely the most memorable one!

Edited February 3, 2023 by Pullstart

[Pullstart 62,905]

42 minutes ago, 953 nut said:

The Dodge I have now has a limited slip differential and I don't have that problem.

My ‘99 Silverado has the G40 gov-lock and it is a game changer in slippery situations.  We call it The Cadillac because of the way it pushes snow, when most open diff trucks tend to slip early.  I’m a huge fan of it!

[ebinmaine 67,555]

7 minutes ago, Pullstart said:

EB, I’d suggest either an air locker, e-locker or limited slip like Richard recommended.  A full spool posi is asking for trouble, until you actually need it.  It’ll chew your tires to oblivion in a quick hurry, unless that slip is available when you don’t need posi.

 

This isn't a full spool solid lock. I'd never put one of them on any kind of a street driven vehicle.

 

This is a gear lock based type that somehow releases tension on the outer wheel while turning.   

[Pullstart 62,905]

2 minutes ago, ebinmaine said:

 

This isn't a full spool solid lock. I'd never put one of them on any kind of a street driven vehicle.

 

This is a gear lock based type that somehow releases tension on the outer wheel while turning.   

So, basically a limited slip.  It allows road manners, but auto locks when there is major slip.  PERFECT!

[ebinmaine 67,555]

7 minutes ago, Pullstart said:

So, basically a limited slip.  It allows road manners, but auto locks when there is major slip.  PERFECT!

 

 

Here's a couple pictures.

I haven't searched the science of it very much but this shows the parts breakdown.

 

 

[cafoose 3,355]

1 hour ago, Pullstart said:

We call it The Cadillac because of the way it pushes snow,

Back about 30 or so years ago I had a '73 Chevy pickup with a plow. I went through several junkyard small blocks plowing snow. I found a Caddy Fleetwood rust bucket for $50. I pulled the engine and put it in the truck. I had to fabricate motor mounts and put in a tranny adapter. Never had an engine problem after that and in low range I could move a mountain 

[ri702bill 8,327]

Eric - a couple of thoughts...

First - be carefull what you wish for....there are several different types of differential locking devices out there that can be retrofitted to an existing axle. Some are either electrically or cable actuated, most like the one you mentioned sense torque and to some extent, tire slippage and then "engage". The last version is a "drop-in" style that replaces the spider gears on the open diff, and can be installed by you with simple hand tools.

Looking at the reviews, three things pop right up as concerns. Rear tire size - they MUST be the same with equal wear. Tire pressure - affects tire diameter. AND - Axle fluid. Be sure to use the recommended type and weight of gear oil  - not sure if a friction modifier addative is required - that was needed on the cone and flat disc clutch plate styles.

Factory installed E-Locker diffs are nice, easy to use, just press the button when needed, press it again to release - what a novel idea!!! MAYBE. These use electromagnetic coils to move the locking device into place, spring force returns it (in theory) Over time, well after the OE warranty is gone, metal shavings inside the axle housing get attracted to the coil - it can engage OK, but not release.

( Got an inquiry from the domestic axle supplier for VW years ago - their mechanical switch would get stuck with shavings - about $900 to fix)

 

The mechanism you linked from Summit looks and works in a similar fashion as an old fashioned 4WD front axle Locking Hub - with the same inherent "problem" See those two rows of teeth shown engaged?? - You have to roll the vehicle 2 or 3 feet to let them truly engage fully - people would get stuck, lock the hubs, move the T-case shifter to 4 High and stand on the gas - that is what breaks the teeth off !!

Similar scenario here - you have to ease into the throttle and decide if all is well.....

[ebinmaine 67,555]

32 minutes ago, ri702bill said:

Eric - a couple of thoughts...

First - be carefull what you wish for....there are several different types of differential locking devices out there that can be retrofitted to an existing axle. Some are either electrically or cable actuated, most like the one you mentioned sense torque and to some extent, tire slippage and then "engage".

 

The last version is a "drop-in" style that replaces the spider gears on the open diff, and can be installed by you with simple hand tools.

Looking at the reviews, three things pop right up as concerns. Rear tire size - they MUST be the same with equal wear. Tire pressure - affects tire diameter. AND - Axle fluid. Be sure to use the recommended type and weight of gear oil  - not sure if a friction modifier addative is required - that was needed on the cone and flat disc clutch plate styles. 

 

The mechanism you linked from Summit looks and works in a similar fashion as an old fashioned 4WD front axle Locking Hub - with the same inherent "problem" See those two rows of teeth shown engaged?? - You have to roll the vehicle 2 or 3 feet to let them truly engage fully - people would get stuck, lock the hubs, move the T-case shifter to 4 High and stand on the gas - that is what breaks the teeth off !!

Similar scenario here - you have to ease into the throttle and decide if all is well.....

 

Excellent row of thoughts there... thanks. 

 

I'll be speaking to the tech department before any purchases. 

 

I'm under the impression that the one I've linked is always engaged as fully locked UNLESS the vehicle is turning.  

I don't understand how it would "know" the vehicle is turning vs just a wheel spinning but that's why I'd call tech first.  

 

 

 

[Rick3478 428]

4 hours ago, ebinmaine said:

I'm considering ordering a diff lock for my 86 f250 so the rear axle would be in full posse all the time.

Wondering if anybody has any experience or comments on these one way or the other...

 

https://www.summitracing.com/parts/pwt-1840-lr

 

 

One thing they neglect to mention is that this introduces backlash into the drivetrain.  If you have manual transmission, there may be banging with every shift.  You didn't specify, so just making you aware.  Having said that, if you are dead set on a pawl-type spool, consider spending the extra money for the deluxe version with synchronizer rings, it's more street friendly.  It's ultimately up to you, but I'd suggest a cone or worm limited slip or an e-locker or air locker first.

[Handy Don 12,233]

3 hours ago, ebinmaine said:

 

This isn't a full spool solid lock. I'd never put one of them on any kind of a street driven vehicle.

 

This is a gear lock based type that somehow releases tension on the outer wheel while turning.   

I get that it “ratchets” the outer (i.e. faster rotating) wheel in forward motion. How does it block the ratcheting mechanism to permit driving in reverse? 

[OutdoorEnvy 1,522]

The truck I've had the last 6-7 years has the G80 GM locker which is a mechanical locking rear diff, limited slip.  From research it's mechanically activated when there is more than 100rpm difference in the wheel speed.  I wasn't sure what I would think of it when I got it but I really like it.  It works well and keeps the fishtailing side swinging on an open diff from happening.  It kicks in when needed so takes the thinking out of it.  I know this isn't ideal for offroading and rock crawling for a dedicated offroad/overlanding rig.  But for use outside of those it is pretty nice and I would plan for any future truck to have it as well.  Something like that may be cheaper and simpler to install compared to the others that have electronics, etc. to also hookup.  

[Blasterdad 2,692]

3 hours ago, ebinmaine said:

This is a gear lock based type that somehow releases tension on the outer wheel while turning.

I have an Eaton Detroit locker in the rear axle of my Jeep & an Eaton True Trac in the front.

It is supposed to "ratchet" but really doesn't, in town if you make a couple of sharp right turns in a row it will suddenly "unload" when you straighten out & sound like a bomb going off under your truck.

I've had it happen a couple of times, the most memorable of which, scared the sh*t out of 2 ladies on the sidewalk, ( they actually flipped me off ).

A locked rear axle is NOT street friendly, in the rain or snow you really have to be on your game or you will be facing the other direction or in the ditch real quick.

And as @Pullstart mentioned, it will eat your back tires up VERY quickly.

The Eaton True Trac is a limited slip, I would go with that or something something similar if you don't want to run an E or Air locker. 

[Blasterdad 2,692]

A company called OX makes a cable controlled locker, it has a billet shift handle for inside the cab, iit can be hooked up to an electric or air actuator too.

I've considered getting one for my CJ-7.

 

https://ox-usa.com/

 

Edited February 3, 2023 by Blasterdad

[wallfish 17,007]

16 minutes ago, Blasterdad said:

 scared the sh*t out of 2 ladies on the sidewalk,

LoL. That coupled with a big diesel and rolling coal on someone would be a wise@ss teenager's dream! LoL

Loud bangs and clouds of black smoke at every corner !

[ri702bill 8,327]

53 minutes ago, ebinmaine said:

I'll be speaking to the tech department before any purchases.

 If he is still there - ask to speak to George - really product knowledgeable and is not the type to talk down to you - smart, but NOT a smarta$$....

I've spoken with him numerous times for aftermarket parts on my Ranger.

[ri702bill 8,327]

10 minutes ago, wallfish said:

LoL. That coupled with a big diesel and rolling coal on someone would be a wise@ss teenager's dream! LoL

Loud bangs and clouds of black smoke at every corner !

There are numerous YT videos about "Rolling Coal". My alltime favorite is the 2 clowns in the bogus Ice Cream truck that pulls up to the unsuspecting folks waiting at the Bus Stop and lets them have it!!!

 

Ever see the YT video of the little ba$tard that installed an air train horn in his car?? Same as above - come up on a small crowd and let them have it!!! Juvenile at best, so wrong but funny.....

[lynnmor 7,307]

I put in a Eaton Truetrac, it was recommended by a local 4X4 shop that does a considerable number of them each year.  They said the road manners are fine and it will do the job off road.  My Super Duty Ford has electronic locking that kicks out a 20 MPH, that makes no sense when pulling a trailer on an interstate and the speed can't be maintained due to traction.

[Horse Newbie 7,071]

13 hours ago, ri702bill said:

as an old fashioned 4WD front axle Locking Hub - with the same inherent "problem" See those two rows of teeth shown engaged?? - You have to roll the vehicle 2 or 3 feet to let them truly engage fully - people would get stuck, lock the hubs, move the T-case shifter to 4 High and stand on the gas

I have a 1981 Toyota Hi-Lux. When I was four-wheelin , I would stop well before “getting stuck” and go ahead and lock my front wheels in, then slowly rolling forward while accelerating easily. Usually I would hear, or feel the teeth engage…

[Horse Newbie 7,071]

11 hours ago, ri702bill said:

Juvenile at best, so wrong but funny

Little A-holes…

[Rick3478 428]

20 hours ago, Handy Don said:

I get that it “ratchets” the outer (i.e. faster rotating) wheel in forward motion. How does it block the ratcheting mechanism to permit driving in reverse? 

 

It's not exactly a ratchet.  In the PowerTrax locker, the usual bevel gears are replaced with a pair of dog clutches which can move side-to-side a little bit.  The cross pin wedges the clutches into engagement when power is applied.  When one of the axles unloads (like outside of a turn) the clutch on that axle can spring back open and let that axle rotate faster.  There is enough side-to-side room for either clutch to disengage, but never both.  So it works in either direction.

 

Operation tends to be a bit jerky, I've heard, and tends to spin the inside wheel on corners, as it's the only one driving.  They make, or used to make, a deluxe version with synchronizer rings that is supposed to be smoother.

[ebinmaine 67,555]

16 minutes ago, Rick3478 said:

Operation tends to be a bit jerky, I've heard, and tends to spin the inside wheel on corners, as it's the only one driving.  They make, or used to make, a deluxe version with synchronizer rings that is supposed to be smoother.

 

I got to poking around in the summit magazine this morning and then did some research online. At this point I'm leaning very heavily towards the

Auburn Gear Grip-N-Loc complete differential.

 

Pricing is good. Auburn reputation is good.

MADE IN THE USA.

 

 

[Tonytoro416 1,034]

This locker is just fine for what you’re trying to achieve EB.   I spend a fair amount of time in the off-road world and have had jeeps and an array of 1/2 ton to 1 ton 4wd trucks.  This locker won’t act like a full spool. Won’t chirp the tires when you turn. Also I assume this is not your daily driver either so this will be just what you’re looking for. This locker could be daily driven don’t get me wrong. I only have one 4wd left and I have had this truck since I was 15. Has a Yukon locker similar to what you’re looking at and it has been driven miles and miles. And we all know 16 year old driver miles are much harder than 25 year old driver miles 😂

This was about 10 years ago and I was daily driving it again raising a young family living in a trailer park. Needless to say the neighbors hated me due to early morning startups lol

Edited February 4, 2023 by Tonytoro416