Locker vs Open

[zimm]

Why would you chose a rear LSD/front locker over a rear and front locker ?

Also why pick a rear LSD/open front over a rear locker and open front ?

Aside from the cost factor, that doesn't make sense.

well...

the lsd is always there and useful in all conditions. if you start to slip, you can fake traction with the brake. if that doesnt work, lock up the front, till you get moving.

when you choose a rear locker, on your primary drive axle, all you have is open, or locked. life isnt usually that simple.

vehicles handle best with an open front, with a selectable locker up there, you get that, but on rare occasions when you need a momentary boost, you can control it.

i think the best combo is the everyday versatility of an lsd in the rear, and the momentary boost of a locker in the front.

conversely, if you lock the front and have an open rear, youre gonna continuously use the front in baaaaad conditions, and tragedy WILL strike.



what would be IDEAL is if someone would come out with a selectable locker that was LSD/locked. than i would put that in the rear.

 

[jfarsang]

what would be IDEAL is if someone would come out with a selectable locker that was LSD/locked. than i would put that in the rear.

That I agree on. :cow:

 

[Scott Brady]

That is what the Rubicon comes with stock. Helical LSD/ Locker in the rear.

 

[jcbrandon]

Also the Power Wagon. Rear is limited slip. And front and rear are electric lockers. Dashboard control is a rotary knob. Normal position is both unlocked. Then rear locked. Then front and rear locked.

 

[Alaska Mike]

well...

the lsd is always there and useful in all conditions. if you start to slip, you can fake traction with the brake. if that doesnt work, lock up the front, till you get moving.

I'd disagree. There are many times I prefer an open differential, and many time where traction is limited and a limited slip is no more effective than an open differential.

when you choose a rear locker, on your primary drive axle, all you have is open, or locked. life isnt usually that simple.

I've never come across a wheeling situation anywhere in the country where I thought "gee, if only I could get one tire to rotate 1/3 of a rotation more than the other..." In my experience, LSDs cause much more tire slippage/traction loss than lockers- and greater traction is the point of having a traction-aiding device, isn't it? Is a LSD more gentle on your drivetrain? I think that depends on your driving style. A locker allows you to drive slower with greater traction than a gear-driven LSD, if you so choose. If you are quickly loading and unloading pressure on the axles, a LSD may be more gentle on the drivetrain (depending on clutch packs or gear design), but I feel a selectable locker will give you options for avoiding that cycling of pressure.

i think the best combo is the everyday versatility of an lsd in the rear, and the momentary boost of a locker in the front.

conversely, if you lock the front and have an open rear, youre gonna continuously use the front in baaaaad conditions, and tragedy WILL strike.

There I would also disagree, as you would have (in most vehicles) the weaker axle dragging the vehicle. A smaller ring and pinion, more splined connections or u-joints... A rear LSD would lessen the disparity, but only partially. Then again, that's just my opinion.

what would be IDEAL is if someone would come out with a selectable locker that was LSD/locked. than i would put that in the rear.[/QUOTE]

The Auburn ECTED Locker is a LSD/e-locker combination, available for the Dana 60.

 

[michaelgroves]

I'd disagree. There are many times I prefer an open differential, and many time where traction is limited and a limited slip is no more effective than an open differential.

I've never come across a wheeling situation anywhere in the country where I thought "gee, if only I could get one tire to rotate 1/3 of a rotation more than the other..." In my experience, LSDs cause much more tire slippage/traction loss than lockers- and greater traction is the point of having a traction-aiding device, isn't it? Is a LSD more gentle on your drivetrain? I think that depends on your driving style. A locker allows you to drive slower with greater traction than a gear-driven LSD, if you so choose. If you are quickly loading and unloading pressure on the axles, a LSD may be more gentle on the drivetrain (depending on clutch packs or gear design), but I feel a selectable locker will give you options for avoiding that cycling of pressure.

Absolutely! The gentleness on the drivetrain of an LSD comes at the price of not allowing full traction. Open diffs are also gentle on the drivetrain (except under certain rather obscure circumstances).

And as regards the LSD's advantage of no driver decisions to be made, I consider that a disadvantage. I like to know what state the diff's in.

Interestingly, for the first year or so (1970,71 or so), the Range Rover Classic's lockable centre diff was an LSD type. Then I think they realised how pointless that was!

 

[I Leak Oil]

Having no experience with a LSD, does it make the rear end squirrely on a short wheel base like a locker does or does it drive more like an open diff?
Jason T.

 

[R_Lefebvre]

I'm really curious about how these things drive with a locked diff on a side slope. Everybody talks about it walking to the low side, and I'd just like to see what that's like. I've not experienced it yet.

My folks have a Yamaha Grizzly 660 and 450. I believe the rear is a spool, then you select 4wd so the center is locked in, and then you can also lock the front diff. So I can get it all locked up. So, if I do that and drive it on a side slope, think it'll behave the same way?

Is it the case that, you can't just turn the front wheels uphill and pull yourself back up?

I'm surprised that a helical LSD on the front would do the same thing. Anybody know why?

 

[michaelgroves]

I'm really curious about how these things drive with a locked diff on a side slope. Everybody talks about it walking to the low side, and I'd just like to see what that's like. I've not experienced it yet.

My folks have a Yamaha Grizzly 660 and 450. I believe the rear is a spool, then you select 4wd so the center is locked in, and then you can also lock the front diff. So I can get it all locked up. So, if I do that and drive it on a side slope, think it'll behave the same way?

Is it the case that, you can't just turn the front wheels uphill and pull yourself back up?

I'm surprised that a helical LSD on the front would do the same thing. Anybody know why?

I would imagine the Grizzly would act the same way, yes.

My take on the side slope problem is that a locked diff induces a little bit of wheel-spin or wheel-skid due to the different paths taken by the wheels (even in a straight line, the ups and downs or tyre diameter differences will force some skidding/spinning). As soon as both wheels on an axle are skidding or spinning, that end of the vehicle can slip sideways more easily, which isn't good on a side-slope.

 

[michaelgroves]

...An open differential always distributes torque 50/50. It must, because it is in fact nothing more than a complicated geared "rotational see-saw".

I just re-read this and I think the see-saw is a brilliant way of describing it! That's precisely what the planet gear does to each of the side-gears in the diff - it pushes against the left one and right one equally, and rotates in the direction of the one that yields most easily.

 

[Storz]

Awesome discussion! I have learned a ton reading through this

 

[TeriAnn]

Awesome discussion! I have learned a ton reading through this

If I didn't already have strong beliefs on the subject, I would walk away totally confused from all the conflicting statements.

As a group, one thing we have in common are strong opinions. Often totally conflicting, yet strong non the less. Looking over the thread I think one problem we are having is that this is a locker vs open diff DISCUSSION INSIDE THE LAND ROVER SECTION.

There are lots of comments made by people who have vehicles that differ significantly from Land Rover weight distribution and traction characteristics. They are very valid comments based upon the characteristics of their own vehicle. An unloaded pickup has very different traction issues from a Land Rover. There are enough differences that people find themselves defending what's best for their vehicle regardless of this being a Land Rover based thread. The Land Rover folks have very similar view points (accounting for coiler vs Series differences) and those with other marques may or may not differ significantly depending upon the characteristics of the poster's own vehicle.

Personally, I think that for the thread to work it should either be cleansed of postings covering non Land Rover vehicles OR be moved to the General vehicle modifications section. As a discussion on Land Rover diff configurations I think it is totally confusing.

 

[jfarsang]

Having no experience with a LSD, does it make the rear end squirrely on a short wheel base like a locker does or does it drive more like an open diff?
Jason T.

In snow/ice and around sharp corners, it can slip/kick out sideways a lot more compared to an open diff.

My preference is a rear open diff with a selectable air locker.

Open diff's are great in the snow/slick conditions while locking it is good for the slow pushing stuff.

Only advantage LSD rear has over an open diff with selectable locker is cost.

be moved to the General vehicle modifications section.

Good point.

 

[R_Lefebvre]

So... couldn't it be said that in most slippery conditions, I'd be better off not locking my CDL? Ie: I'm on a mostly level muddy, rutted road. Wouldn't I have better stability and manoeverability with the center diff unlocked?

I locked it as a matter of course, but it begs the question.

 

[Hank]

We could talk about that for another 10-pages......so, just try it and see.