Locking Diff question

[Stellaghost]

Just to point this out, one problem with locking diffs, limited slip, atb etc is that they are very good at letting you lose your driving skills, you get too reliant, you put them on just in case when actually a few months ago you would have driven over a particular obstacle with no driving aids

I've seen people lock them in from start of play, don't see the point in that whatsoever, mine go in when an obstacle is defeating me or if the terrain is that ridiculous it is the sensible option of I'm doing modified trials

just my ten pence worth regards Stephen

[FridgeFreezer]

6 minutes ago, Stellaghost said:

Just to point this out, one problem with locking diffs, limited slip, atb etc is that they are very good at letting you lose your driving skills

Dare I say portals are even worse for that not that I had any skills beforehand  you get used to just being able to drive anywhere without thinking.

[Stellaghost]

1 hour ago, FridgeFreezer said:

Dare I say portals are even worse for that not that I had any skills beforehand  you get used to just being able to drive anywhere without thinking.

They probably are......

But all the locking devices available aren't going to let you drive when your diff case is grounded and your wheels are spinning in fresh air........

There's a limit to how big you can go with tyres due to the depth of ruts, portals kind of help with that........

Regards Stephen 

[Carloz]

On 7/6/2022 at 8:55 AM, Snagger said:

ATBs are control-free and will react the moment a wheel spins up.  They don’t fully lock, so won’t have quite the effectiveness with a dangling wheel as a full locker, but should keep or get you going.  They don’t need a potential pause to engage to avoid spline damage, though a full locker shouldn’t suffer significant spline grinding if engaged before the wheels spin up differently; the ATB is permanently “engaged”.  They will still provide the tractive benefits without having to be disengaged on the road, so provide the benefits on snowy road without trying to force skids while cornering.  Unless you are doing a lot of aggressive off roading, especial rock crawling or deep mud, ATBs should give better overall results than full lockers.

It doesn’t hurt that they are also cheaper, easy to fit with no control runs and casing drilling, and don’t need extra maintenance.

 

Detroit was working on a ATB which is lockable too. So, an ATB and full locker in one. That would be the best of both worlds and much more expensive of course.

That was before Detroit was taken over by Eaton. After that I never saw anything about it anymore, anywhere... 

[Escape]

7 hours ago, Carloz said:

 

Detroit was working on a ATB which is lockable too. So, an ATB and full locker in one. That would be the best of both worlds and much more expensive of course.

That was before Detroit was taken over by Eaton. After that I never saw anything about it anymore, anywhere... 

That would be the best of both worlds, like the ATB center available for the LT230.

On 7/7/2022 at 10:46 AM, FridgeFreezer said:

On the contrary - I'm fairly sure the modern stuff will walk all over the old school stuff with less drama, less user interaction/skill required and in a safer and more controlled manner... but that's not really why we do this!

If I just needed to cross terrain with minimum fuss I'd go for modern stuff every time (reliability/survivability factors notwithstanding) much like I'd choose a full size Disco or Range Rover with all the gizmos if I had to tow a trailer all the time.

I have to disagree, as good as they are electronics can never beat a 100% locked diff. And they only react when traction is lost, where a manual locker can be engaged in advance. I saw this some years ago while laning my Defender with a Range Rover Sport. Both on roadtires (because I just had an MOT and didn't find time to swap tires again), the Range Rover had me beat for ground clearance as my Defender was on the standard 205R16s but on a slope with wet grass it struggled to find traction, spinning and digging in before TR could react. I could engage both lockers and drive off without any fuss. Like @Snagger I want full control (which is why I dislike pretty much all modern cars), but that also implies it all comes down to the driver. The modern stuff will get you pretty much anywhere you want to go, be it on or off road, without having to think twice. But that doesn't make it better, just easier.

[Ed Poore]

Where traction control comes into its own is more likely in loss of traction on steep descents.

I've been in situations where engine braking isn't enough as it runs away a little so careful application of the brakes is required. The more modern traction control stuff can control the braking on individual wheels so there are times where it can be beneficial. Not many I grant you but some none the less.

[geoffbeaumont]

16 hours ago, Ed Poore said:

Where traction control comes into its own is more likely in loss of traction on steep descents.

I've been in situations where engine braking isn't enough as it runs away a little so careful application of the brakes is required. The more modern traction control stuff can control the braking on individual wheels so there are times where it can be beneficial. Not many I grant you but some none the less.

Doesn't have to be terribly modern for that - the ABS system on late Range Rover Classics was independent on each wheel and very effective in situations like that (which was useful, because auto RRCs pretty much always need some brakes on descents).

If you had the traction control option, that only operated on the back axle, but it was independent on each wheel and surprisingly effective.

[FridgeFreezer]

17 hours ago, Escape said:

I have to disagree, as good as they are electronics can never beat a 100% locked diff

Since the D3 they've been available with locking diffs as well, the off-road pack for the new Defender includes at least a rear locker and the ECU will engage it in certain modes.

[Retroanaconda]

Yes terrain response is partially proactive and partially reactive, as in certain modes it will lock or pre-load the diffs ahead of any traction loss. And to be fair the reactive bit of it is incredibly quick, you don’t really notice it working other than some clicking from the relays and/or brake pump and there’s not much if anything in the way of wheel scrabbling while it figures it out. On models without the rear diff lock there would probably be a bit more.

However in an old Defender I would choose to have a manual locking diff because for me that’s what they’re all about - I like the simplicity of making the driver inputs myself. I also like the idea that it’s not there until you need it, so seems the ideal solution in a ‘best of both worlds’ kind of way similar to an overdrive.

[Carloz]

22 hours ago, Escape said:

That would be the best of both worlds, like the ATB center available for the LT230.

Exactly!

But I guess Eaton's marketing department figured out that most people would choose for ATB OR Full Locker because of the higher price tag of the ideal diff...

Like Detroit was managed more by enthousiasts and Eaton, the new owner of Detroit, more by people with the calculator....

[bishbosh]

I’m just going to throw this out there…… low traction side slope and locking diffs…..😳

[garrycol]

Yes I have often read about this on forums but after 16 years offroad driving in all conditions with a detroit in the back of my 101 I have never experienced this.

I also have a dual locked, portal Haflinger for 10 years and never noticed it in it there either.

However I can understand the issue arising in low traction side slopes where too much power is being applied causing wheels to break traction then of course they will slide sideways down the slope.

Edited July 14, 2022 by garrycol

[Escape]

13 hours ago, bishbosh said:

I’m just going to throw this out there…… low traction side slope and locking diffs…..😳

As above, go easy or leave the diffs unlocked. I'd still prefer to be in control rather than trust the electronics to make the right call.

[deep]

A friend has a Detroit in the back of his 90.  Most of the time it really is great but I recall two occasions when it, quiet violently, kept throwing the car in the wrong direction.  On balance, I'd happily fit one to my Series 3 but I'd prefer to be able to engage or disengage a locker at will.

[garrycol]

There are Detroits and there are Detroits - older units from the 60s, 70s and 80s often tended to do that but the modern SoftLocker versions dont do that.

[deep]

4 hours ago, garrycol said:

There are Detroits and there are Detroits - older units from the 60s, 70s and 80s often tended to do that but the modern SoftLocker versions dont do that.

I love this site.  Learn stuff all the time!

[Maverik]

So my thoughts: I fitted an ATB to the rear of the 90 in 2019, why? Not entirely sure other than curiosity and because i was looking for an "upgrade", I mainly drive tarmac roads and more recently the odd forestry track or grass field. What I wasn't really prepared for was how much nicer the truck handled on the road, especially in wet/wintery weather, its much more sure footed, meaning it feels much more controlled cornering.

So impressed with the much nicer road handling I've ordered a 10 spline trutrac rediculously heavy duty build spec'd diff from Nige for the front which I'm planning to get fitted before winter comes in. Fun times 😁 quite the ATB fan.

[Hybrid_From_Hell]

And being such an unusual exotic build a video will be made for the webshop as these help others understand options build specs and give them an understanding of what to upgrade to 😎

[Snagger]

On 7/16/2022 at 7:12 AM, Maverik said:

So my thoughts: I fitted an ATB to the rear of the 90 in 2019, why? Not entirely sure other than curiosity and because i was looking for an "upgrade", I mainly drive tarmac roads and more recently the odd forestry track or grass field. What I wasn't really prepared for was how much nicer the truck handled on the road, especially in wet/wintery weather, its much more sure footed, meaning it feels much more controlled cornering.

So impressed with the much nicer road handling I've ordered a 10 spline trutrac rediculously heavy duty build spec'd diff from Nige for the front which I'm planning to get fitted before winter comes in. Fun times 😁 quite the ATB fan.

Exactly what I’m after and am expecting, having studied their workings.