Rear diff lock

[Snagger]

The Detroit lockers are reputed to give unpleasant handling on the road and make a lot of noise.  The way they work would force a tyre to lose grip on a slippery road, wet or icy, when going around bends or corners.  I’m surprised they’re road legal.  An LSD or ATB is much safer on the road, though perhaps not as good with a wheel lifted.

[garrycol]

25 minutes ago, Snagger said:

The Detroit lockers are reputed to give unpleasant handling on the road and make a lot of noise.  The way they work would force a tyre to lose grip on a slippery road, wet or icy, when going around bends or corners.  I’m surprised they’re road legal.  An LSD or ATB is much safer on the road, though perhaps not as good with a wheel lifted.

Well I have had a detroit in the rear of my 101 for 12 years and none of the above apply - no unpleasant handling and no noise - you would never know it is there.  They work perfectly and in my view are the optimal locker for the rear - relatively cheap and quietly get on with the job without you knowing it is  there.

 

Garry

[Snagger]

Canberra isn’t known for its snowy roads, though. 😉  You do mean the spring loaded ratcheting diff that is normally locked but spill pop and skip if there is enough wind up from side to side, right?  That is the Detroit Locker.  The Detroit Trutrac is something very different, but is often mixed up with it.

[garrycol]

2 hours ago, Snagger said:

Canberra isn’t known for its snowy roads, though. 😉 

You are kidding arnt' you - our alpine region here has a larger area than the Swiss Alps.  Of course we have snowy roads - just not so much in the city.

I have a Detroit locker and as said - in my vehicle for 12 years - driven on road, off road, beach, and snowy roads.  I know nothing about a TruTrac.

These two pics are just 10km in a straight line from my house in the suburbs of Canberra.  Snows in the city a few times each year but generally clear but the surrounds are covered in heavy snow late May to September though season is getting shorter with global warming - we used to even have a ski club and run from the early 30s.

 

 

[Ed Poore]

9 hours ago, andy _1 said:

"if that wheel would just turn" i would not have to winch  myself out hence the auto locker an air locker seems way over the top for me

Are you familiar with or have you tried left foot / cadence braking? Before I had the lockers it was surprising how much further you could get by applying that technique.

One thing I will say of full lockers over ATBs and the like. They can be used pre-emptively rather than reactively, i.e. lock them before you know you're going to lose traction that way you don't stop / lose momentum "waiting" for them to engage.

[Jon W]

I haven't read the whole thread, but if it hasn't been mentioned already. I would probably be easiest to swap to a later 24spline disc braked rear axle. As then you have more choice of shafts/ easier to get hold of. Also benefit of disc brakes which are easier to clean and service after off road use. 

 

Jon 

[Escape]

11 hours ago, andy _1 said:

It not really getting stuck as such.  I have been stuck unteen times standing looking at solid ground  at the opposite wheel and thinking ,"if that wheel would just turn" i would not have to winch  myself out hence the auto locker an air locker seems way over the top for me or just save money and winch away. I read stories of them not being good in short trucks , but then I read posts from guys that know about lockers saying they are great. So I'll bit the bullet one day

It's not as simple as that. With better tyres, the wheel(s) on soft ground will give more traction for longer, so the other wheels will also have more torque available, even with open diffs, and you're bound to get a lot further. That doesn't apply to rockclimbing etc where one wheel is actually in the air of course. A typcial demonstration of lockers (or advanced traction control/terrain response) is to get 1/2/3 wheels on rollers and prove the vehicle can still drive. Regardless of the type of tyres. But that's not really comparable to off roading, with good tyres you'll have an advantage everywhere. Even more so if you air them down to get even more grip. With less agressive tyres you'll end up using the locker mainly to overcome the lack of grip. Much like most modern 4x4s that can't have muds fitted (for comfort, speed rating etc) but compensate with all kinds of electronics, including lockers, to offer  (in some cases even properly good) performance off road.

Don't get me wrong, I do like lockers and love my Ashcroft airlockers. But only as part of a complete package, i.e. with the best tyres (within reason) for the job as well. From the picture you're painting, tyres would be the most logical upgrade. If you insist on a locker, an ATB would be my preference. Easier on the shafts and very good value for money. No hassle with a compressor and such.
On that note, I found the ARB compressor a very good piece of kit and certainly capable of pumping up several big tyres. But unless you need it for a locker, a big Tmax will be cheaper and a lot faster. You'd want to add a small tank and pressure control if you use one for lockers, so as not to blow the seals or have incomplete engagement because of pressure being too low.

Filip

[andy _1]

Thanks I have nothing against mud tyres, I'll put a set on when the ones on are a little more worn, thats all  20 mins all changed. I was looking at the ashcroft atb its sold out , not a bad word about it.in the end its my choice and I thank everyone for input. I hate buying something and fitting it  or whatever and then finding out about product x is just as good at half the price. When it comes to this atb from ashcrofts anyone know anything I should be aware off. It seems to tick all the boxes for me.

[Chicken Drumstick]

8 hours ago, garrycol said:

Well I have had a detroit in the rear of my 101 for 12 years and none of the above apply - no unpleasant handling and no noise - you would never know it is there.  They work perfectly and in my view are the optimal locker for the rear - relatively cheap and quietly get on with the job without you knowing it is  there.

 

Garry

I think people tend to complain about Detroit lockers more so in the front than the back. But I've not run them, so don't really know for sure. But from what I've read, it is normally lighter shortwheel base vehicles that they seem to be more unpleasant in. I know a 101 isn't super long wheel base, but they have a bit of heft about them. And I suspect probably aren't driven on road in the same way a 90 can be in the corners. Glad that setup works for you though. And some cool pics.

[Mo Murphy]

Lockers are not much cop without appropriate tyres. You'll just spin both wheels on the axle instead of one.

 

You will break even HD parts if you drive without any mechanical sympathy.

 

The best line through an obstacle is often worth far more than a locker and a winch.

 

HTH

Mo

[reb78]

16 minutes ago, Chicken Drumstick said:

I think people tend to complain about Detroit lockers more so in the front than the back. But I've not run them, so don't really know for sure. But from what I've read, it is normally lighter shortwheel base vehicles that they seem to be more unpleasant in. I know a 101 isn't super long wheel base, but they have a bit of heft about them. And I suspect probably aren't driven on road in the same way a 90 can be in the corners. Glad that setup works for you though. And some cool pics.

Reading various forum threads, it seems that those who don't and have never run Detroits don't like them but people who do run them and have them setup properly say they are fine.

[Chicken Drumstick]

2 minutes ago, andy _1 said:

Thanks I have nothing against mud tyres, I'll put a set on when the ones on are a little more worn, thats all  20 mins all changed. I was looking at the ashcroft atb its sold out , not a bad word about it.in the end its my choice and I thank everyone for input. I hate buying something and fitting it  or whatever and then finding out about product x is just as good at half the price. When it comes to this atb from ashcrofts anyone know anything I should be aware off. It seems to tick all the boxes for me.

The ATB's are great. If you fit one at the front you'll feel it through the steering a little on road, just as you would with a fwd hot hatch that has a limited slip diff. Your choice if you go both axles or just one. If one axle, most would fit just one to the rear, but some would fit to the front for other reasons. Neither is really wrong.

But they'll help out in wet, snow or icy conditions and you'll not need to do a thing, just keep driving. the only time they don't work so well is if you have wheels waving in the air, but in these situations a dab of left foot braking is all you are likely to need and they will work fine. And if you have ATB's in both axles, one wheel in the air won't matter anyway. Easiest thing on a 90 is to fit a Disco axle on the back to get the 24 spline axles and rear disc brakes. At the front you can buy extra bits from Ashcroft to fit the ATB and shafts, but again might be cheaper to buy a latter axle and retro fit. Just check on if you have wide/narrow front radius arms. Upgrading the half shafts is recommended with the ATBs, but not essential. You could always wait until you break a standard one and upgrade then.

However, I'd say it is about a complete package, the right tyres for the job (bit like wearing the right footwear for yourself, you wouldn't walk out in the deep mud in some trainers or slippers) will make a huge difference too. And also some simple suspension changes can help out hugely. You don't need to go radical on the suspension, but a bit more flex and droop can make a huge difference to how often you get, or rather don't get cross axled. Something as simple as standard rate longer springs and some longer shocks.

 

Here are two open diff vehicles. Both with slight suspension mods. But note the difference in how they handle the terrain (same driver). A 100% standard 90 would get stopped a lot easier and in fact did so on the trail day when people were running the course.

 

[garrycol]

51 minutes ago, Chicken Drumstick said:

I think people tend to complain about Detroit lockers more so in the front than the back. But I've not run them, so don't really know for sure. But from what I've read, it is normally lighter shortwheel base vehicles that they seem to be more unpleasant in. I know a 101 isn't super long wheel base, but they have a bit of heft about them. And I suspect probably aren't driven on road in the same way a 90 can be in the corners. Glad that setup works for you though. And some cool pics.

You do not put detroit lockers in the front without the use of free wheeling hubs - you will not be able to steer.  Yes the 101 wheelbase is 101" but they are lighter than a 110 and less than 100kgs heavier than a 90.

[missingsid]

The Detroit lockers are reputed to give unpleasant handling on the road and make a lot of noise.  The way they work would force a tyre to lose grip on a slippery road, wet or icy, when going around bends or corners.  I’m surprised they’re road legal.  An LSD or ATB is much safer on the road, though perhaps not as good with a wheel lifted.

I've read, it is normally lighter shortwheel base vehicles that they seem to be more unpleasant in.

 

I have experienced a DL in the rear of a Mustang engined CJ2 driven by an ex stock car driver and AWDC trials champion, when it snapped sideways in traffic it sure woke both of us up! The previous owner had put it on its side.

[Anderzander]

I had a Kaiser Locker in the back of the 90. That was supposed to be better than the DL.

It locks both wheels to the direction and speed of drive but allows either wheel (but only 1 at a time) to be turned faster than the drive input so as to allow for a different distance of wheel travel. Neither wheel can travel slower than the Ring Gear but either wheel can travel faster (but not both together).

I think unlike a Detroit or other permanent locker it takes almost no force to allow a wheel to turn faster and allow for differences in travel distance such as in a turn (i.e. no under steer) or on uneven ground and without compromising the drive lock.

 

My own experience of it was:

On road - it was fine to live with and only really noticeable on a bend with a neutral throttle, where it would feel like it was alternating between locking and unlocking. This was most pronounced at very low speeds.

However where it was being driven - i.e. the accelerator was being pressed and there was drive going through it, such as using the accelerator through a bend - then it behaved perfectly.

My understanding was that those who had it with an Automatic transmission, then even on neutral throttle, it seemed to have achieved the holy grail of being a totally transparent auto locker.

Off road (and on my manual transmission) it was noticeable only in an occasional noise when on say rocks that moved - so from grip to slip and so on.

[oneandtwo]

20 hours ago, andy _1 said:

Thanks I have nothing against mud tyres, I'll put a set on when the ones on are a little more worn, thats all  20 mins all changed. I was looking at the ashcroft atb its sold out , not a bad word about it.in the end its my choice and I thank everyone for input. I hate buying something and fitting it  or whatever and then finding out about product x is just as good at half the price. When it comes to this atb from ashcrofts anyone know anything I should be aware off. It seems to tick all the boxes for me.

I have the Ashcroft ATB in the rear of one 90, a Truetrac ATB in another 90 and a Quaife ATB in a series.

The Quaife is the best made but was twice the price of the Ashcroft, but was the only ATB still available with a 10 spline option. Once fitted there is no discernible difference between any of them; they were all fitted due to driving on sand and launching / retrieving a boat on sand, and in my application were well worth fitting. I would go for the Ashcroft if I were to fit another, I have one here to fit to the rear of a friends 90 who uses his in the same way.

 

[Anderzander]

1 hour ago, oneandtwo said:

....but was the only ATB still available with a 10 spline option.

 

I thought 10 spline truetracs were still available?

[landroversforever]

I thought Ashcrofts stopped doing the Detroit and the truetrac as the supply of them and parts was drying up? 

[reb78]

On 2/12/2021 at 11:44 AM, landroversforever said:

I thought Ashcrofts stopped doing the Detroit and the truetrac as the supply of them and parts was drying up? 

This thread stimulated me to look at options for my rear Salisbury. I really dont think I need a locker having said that... I have been nearly stuck once on a very wet muddy field but dont tend to get into very sticky spots often. But, Ashcrofts show the Detroit in stock...

Edited February 14, 2021 by reb78

[Snagger]

On 2/11/2021 at 8:24 AM, garrycol said:

You are kidding arnt' you - our alpine region here has a larger area than the Swiss Alps.  Of course we have snowy roads - just not so much in the city.

I have a Detroit locker and as said - in my vehicle for 12 years - driven on road, off road, beach, and snowy roads.  I know nothing about a TruTrac.

These two pics are just 10km in a straight line from my house in the suburbs of Canberra.  Snows in the city a few times each year but generally clear but the surrounds are covered in heavy snow late May to September though season is getting shorter with global warming - we used to even have a ski club and run from the early 30s.

 

 

 

That is far more than I thought you got there.  I had understood the snow mostly came a bit further north.  Good to learn something.