Lockers on a 6x6 defender?

Quote:

---

Originally Posted by Brian Hjelm

You will never get good articulation from a four spring and rocking shackle suspension. They don't even load share properly only in theory. This is why a previous poster was busting his rear diff. I bet when ramping, the middle axle was off, or barely touching, the ground. Reyco four spring suspension on heavy prime movers and trailers was considered a highway suspension. You need a single point suspension like a Rockwell six rod.

---

I agree with you about poor articulation/load sharing with 4 spring arrangements, but there are limits to any design once an axle on a tendem set bottoms out on up travel, and that is the scenario where I busted rearmost diffs with my inverted, centrally pivoted 2 spring 6 rod design.
Bottoming out on uptravel and overloading of the rearmost differential/axle occurrs when transitioning from relatively level ground to a steep gradient, and is significantly harder on drive components than when transitioning from the gradient to level ground, where the leading axle will bottom out on its bumpstops.

Just because the SAS don't have too many problems means bugger all. They are into getting the job done and surviving. That means do not abuse your equipment unneccesarily. I could be wrong, but I doubt their vehicles are carrying the full 2 ton rated payload either.
Bill.

Quote:

---

Originally Posted by wagoo

Just because the SAS don't have too many problems means bugger all. They are into getting the job done and surviving. That means do not abuse your equipment unneccesarily. I could be wrong, but I doubt their vehicles are carrying the 2 ton rated payload either.
Bill.

---

If you are implying they don't go on patrol loaded up to 2 ton,then think again.

Even the 4x4s are going out loaded to the bump stops.

Let me tell you that if the Army aren't breaking it then it is bloody strong, this is first hand experience.

Quote:

---

Originally Posted by lambrover

If you are implying they don't go on patrol loaded up to 2 ton,then think again.

Even the 4x4s are going out loaded to the bump stops.

Let me tell you that if the Army aren't breaking it then it is bloody strong, this is first hand experience.

---

I'm offering first hand experience from an engineering perspective.
Sorry, quite unconvinced by your argument above, that is disproved by the fact that the army previously spent 30 odd years operating series 2/2a/3s LandRovers with their fragile gearboxes and differentials with 10 spline toothpicks for axles in the case of 2/2As.
A 4x4 1ton Landrover loaded to the bumpstops is less critical with regard differential/axle strength when compared to a 2 ton 6x6 that runs out of articulation in the rear bogie in a cross country scenario. The rear axle of the 4x4 will still only have to pull the 1 ton payload plus rear tare weight up and over the gradients, wheras the individual differential/axles of a tandem bogie will in the instances described in my previous post be subjected to the full 2 ton payload plus the additional tare weight of the larger more heavily constructed rear chassis/body unit.
There are even 4x4 110 owners out there breaking 24 spline halfshafts. if there weren't then companys such as Mcnamara, GBR and Ashcrofts wouldn't be offering the 35 spline 1.5'' option, would they?


I appreciate that this thread is not really about tandem drive rear bogie suspension design, but IMO the only true cross country arrangement for extreme terrain is a gear driven version of the road grader style bogie as used on Scammell Pioneers, Explorers, and later Leyland Martian heavy 6x6s. A lighter version of this system is available for HUMVEES. The operation of these bogies is all viewable on You Tube but I'm hopeless at links.
Bill.

Quote:

---

Originally Posted by wagoo

I'm offering first hand experience from an engineering perspective.
Sorry, quite unconvinced by your argument above, that is disproved by the fact that the army previously spent 30 odd years operating series 2/2a/3s LandRovers with their fragile gearboxes and differentials with 10 spline toothpicks for axles in the case of 2/2As.
A 4x4 1ton Landrover loaded to the bumpstops is less critical with regard differential/axle strength when compared to a 2 ton 6x6 that runs out of articulation in the rear bogie in a cross country scenario. The rear axle of the 4x4 will still only have to pull the 1 ton payload plus rear tare weight up and over the gradients, wheras the individual differential/axles of a tandem bogie will in certain instances be subjected to the full 2 ton payload plus the additional tare weight of the larger more heavily constructed rear chassis/body unit.
There are even 4x4 110 owners out there breaking 24 spline halfshafts. if there weren't then companys such as Mcnamara, GBR and Ashcrofts wouldn't be offering the 35 spline 1.5'' option, would they?

I appreciate that this thread is not really about tandem drive rear bogie suspension design, but IMO the only true cross country arrangement for extreme terrain is a gear driven version of the road grader style bogie as used on Scammell Pioneers, Explorers, and later Leyland Martian heavy 6x6s
Bill.

---

I am saying they are carrying more then 2 ton and the 4x4 is carrying more then 1 ton, they are often on the bump stop with 130 springs in them.

The work shop GMV 6x6s are always going out over loaded, the weight of the pod is so heavy that by them time you put your pers gear in you are over weight. I am not going into what or how much the LRPV carries, I am sure you understand why.

Quote:

---

Originally Posted by wagoo

I could be wrong, but I doubt their vehicles are carrying the full 2 ton rated payload either.
Bill.

---

Yes, you would be...

one of the sets of pairs Ive had to prep required us to crossload between 2 of them and dump some stuff on a pallet before the airload team would accept it as it was over GVM.

Quote:

---

Originally Posted by Blknight.aus

Yes, you would be...

one of the sets of pairs Ive had to prep required us to crossload between 2 of them and dump some stuff on a pallet before the airload team would accept it as it was over GVM.

---

Preparing them for air transport with all their kit and spares etc, doesn't mean they go out on patrol with all that gear.
Regardless, the armys idea of what constitutes cross country ability is nowhere near what the average adventurous recreational 4wder would deem adequate. Otherwise they would have had difflocks fitted to their oversprung 110s. And I state that from personal experience as a former Grunt.
Bill.

Quote:

---

Originally Posted by wagoo

Preparing them for air transport with all their kit and spares etc, doesn't mean they go out on patrol with all that gear.
Regardless, the armys idea of what constitutes cross country ability is nowhere near what the average adventurous recreational 4wder would deem adequate. Otherwise they would have had difflocks fitted to their oversprung 110s. And I state that from personal experience as a former Grunt.
Bill.

---

Bill you may be a former grunt but Dave and myself are currently inn and repair these vehicles, they are commonly over loaded out field.

And as for the average adventurous 4wder most are not interested in rough stuff and a dirt road is as much as most 4x4's see.

Yes the rear suspension may not be the best set up but we are both saying that it isn't breaking.

Quote:

---

Originally Posted by wagoo

Preparing them for air transport with all their kit and spares etc, doesn't mean they go out on patrol with all that gear.
Regardless, the armys idea of what constitutes cross country ability is nowhere near what the average adventurous recreational 4wder would deem adequate. Otherwise they would have had difflocks fitted to their oversprung 110s. And I state that from personal experience as a former Grunt.
Bill.

---

Mate no offence but being told that a vehicles "not being used to or beyond capacity" by someone whose basic function in life was to walk and die in a loud noisy fashion as a warning system to the rest of us doesn't exactly inspire faith in the validity of the original statement.

Dave, would you say about as much validity as your " no offense" comment..... ;)

probably less. ( he may also not know that as well as being RAAF Im also Ex AJ)