bill van snorkle

I prefer what I have. 3 link with the third link above the diff, the lower links dropped 2 1/2'' from the stock position, all links made from rear lowers with the pin end of scrap front radius arms welded into one end. 9'' of vertical separation at axle, 4 '' at chassis. If you use a wristed arm, be sure to strengthen the brackets on the non wristed side as they will be under greater stress. The resistance to torque reaction will be much less with a wristed system, so expect axle hop. When a stock radius arm, or a 3 link articulates at speed, the castor change is minimal, but when a wristed axle articulates at speed the castor change can make for some spooky handling. You would probably get better overall performance if you removed the left front radius arm bolt and modified the axle bracket to provide clearance for that end of the radius arm to go up and down unhindered and without damaging either the axle bracket or the bushing. I am not convinced about slotted bushes. the gain in travel would be limited at best, and I could be wrong but I think the slots would compromise torque reaction control under brakes and under power. Bill.

Will, I know a bloke from Dorset (Richard Watton) who once had a 6x6 Stalwart. He made front and centre axle disconnects to make it 6x2 when used on road. The Stalwarts and Saracens had a Detroit No Spin in the single differential, so windup would be a bigger problem. When the Australian military sold off their Ferrets many years ago, a few were bought by farmers hoping they would make a resonable tractor, but the mechanical gear reduction was quite tall, around 34:1 and quite a few cooked the fluid flywheel when trying to pull heavy loads. By ''Curbed'', do you mean bouncing off curbs? I read somewhere that was another method of relieving windup stress on them when driven on sealed roads. Bill.

Ferrets have what is known as a "H'' transmission system. Basically they have a single conventional differential behind the gearbox approx at midwheelbase. The halfshafts of this differential each go out to a bevel gear box on each side and then individual driveshafts go for and aft to right angle drives at each wheel. The problem is that on Ferrets,in spite of all the engineering and complexity, the single differential is not lockable, so that when a wheel loses traction and spins, the other wheel on the same side spins too, and both wheels on the other side go on strike and do nothing. The other problem is transmission windup on hard surfaces because the front and rear wheels on each side are permanently driven together without any front to rear differential.Windup really eats up the fragile bevel boxes apparently.I think the Ferret operators manual recommends that the driver alternately run each pair of wheels on each side on the soft shoulder of the road every 5 miles or so to releive windup .I don't know how you do that without driving on the wrong side of the road occasionally. The only thing I like about Ferrets is that they have epicyclic hub reduction, and a couple of years ago I unsuccessfully searched for a set of Ferret hubs to build a facimile of the Roadless Traction Land Rover, sometimes called the Forest Rover. Bill.

Here's an idea to toss in to the ring. I started to build a 4wd VW beetle some years ago but then met my wife to be and the project didn't get completed. Anyway for the front end I used a Kombi twin transverse torsion bar assembly, and instead of bolting it to the chassis as per normal, I mounted it on a centrally pivoted bushing with a longditudal control arm on each side.I bolted a Suburu rear diff, concentric with the centre pivot to the transverse assembly. I figured that way I would have an independant front end with unrestricted articulation.It's time for bed and the rest of the story is too long winded to repeat here. Bill.

Yes the swing axles are very short, and the camber change is pretty scarey. I hope you can come up with something out of the box that works well under most conditions. Thanks for posting the UAZ axle cross section BTW. Bill.

I think it really depends on the conditions you want to compete in. I am still not convinced about stability of independant suspension in relatively low speed severe axle articulating stuff. The Hummer on the ramp episode and watching Haflingers and Pinzgauers getting all tippy in places where a beam axled 4x4 just walks through is what sticks in my mind when independant suspensions are mentioned. Bill.

Too many bits below axle centreline. Take a look at a Jaguar rear end. The upper lateral control arm is the universally jointed halfshaft. The bottom control arm is a tubular link rod. Now redesign it for offroad use by making the halfshaft the lower link and placing the former lower link above. Articulation will still be not as good as beam axles though. Bill.

Humvees have independant suspension and inboard brakes which means the portal boxes do not have flanges to adapt to beam axles, or brake caliper mounting points, so it makes them difficult to fit the closed swivel housings as on LandRovers etc. The gears, shafts, bearings etc look good , the drop is 3 3/4'' compared to around 4 1/2'' for Volvo's and Mogs, but if they were available cheaply enough, for anyone with fab and machining abilities it's not to difficult to make some steel boxes to suit. I wish I had a load of Hummer gears and shafts when I was making my own portals. Apperently there are lots of them at the US military garbage dump in Bagdad. Anyone care to go there for a scrounge? Bill.

Not quite Epicyclic. It appears to be a large internally toothed ring gear at the output(wheel) end, driven by a smaller pinion gear at the diff end. similar to some forklift axles I have seen. Should be quite strong due to having several gearteeth in mesh, but to get much drop or lift the hub ratios would have to be very low. A guy in Aus (Glen Dobbins) built a set for his FJ40. They only had 3'' drop but the ratio was about 3.7:1 Bill.

All I seem to read about is comps, comps, comps. Is that what offroading in Britain has come to ? Don't people build vehicles up to use on extended trips into wild country anymore? I could care less whether a winch challenge or any other form of offroad motor sport bans portals. I built my vehicle for family weekend trips into the high country, where the only competition is between my truck, myself and the condition of the tracks that nature is continually modifying in an attempt to inhibit my progress. Our government is gradually closing down many tracks in areas handy to Melbourne, so eventually we will be forced to travel further afield or participate in comps to have a bit of fun Thankfully it is still possible to travel to wild remote areas where one may only see one or two other vehicles in a whole days challenging driving in conditions where high mobility, high reliabilty and self sufficiency are paramount. While these opportunities are still available to me I say sod the comps with all their restrictions on what modifications I can or cannot do to my own vehicle. Bill.

If you want to see terrain where portals are of real use take a trip down to Victoria where you can barely move on 35 inch tyres with straight axles. Quite a few of the serious lads are regularly out there digging ruts on hills with 38'' tyres , rain makes the ruts deeper. I can't afford to buy larger and larger tyres every couple of seasons, and at any rate 36'' are the maximum legal diameter here, so portals make a lot of sense. The only setup that equalled my portals for sheer mobility was when I used to run 35 spline Salisbury rear, 24 spline Salisbury front. with duall wheels all round. The outer wheels were 35'' TSL's the inner wheels were 32 '' 7.50x16' Bar Grips. due to the very narrow inner wheel track width of 41'' rear and 49'' front, the cross axle ramp angle was very steep as the diffs were very close to the right hand side inner wheel...Combined with a rear wheel track of 65'' and a front of 73'' there wasn't a set of wheel ruts anywhere that would catch the truck out. In fact, applying the "V'' belt in a groove principal ,deep ruts on steep, slippery and otherwise impassable hills were used as a source of extra traction rather than something to be avoided. Now all I have to do is make up a set of inner duall wheels that will fit right over my portal boxes and I can die a happy man. Bill.

Thanks Steve. I haven't grown up yet either, and I think it's too late to start now. But alas the young things stopped looking at me decades ago. sigh, oh the memories.

The broken wire spring would affect the performance of the synchro baulk ring that it belongs to, as there is no longer anything there to apply pressure on the baulk ring and relevant gear to adjust its speed before the dog ring tries to grab it. Bill.

I wish I could say that about myself. I turned 56 today, and I felt a lot better at 55. Happy birthday LR4x4. Bill.

I am only guessing here, but I think the UK and Australian for that matter competition scene will evolve and courses will be designed to accomodate proper offroad cross country vehicles. Then the superiority of well designed portal axled competition rigs will become clear. It has been said that no Portal axled truck has ever won the Malaysian Rainforest Challenge. I have prepared 3 pairs of ex Malaysian RFC Volvo axles that were under LandRovers over there, and the dogs breakfast that I had to remove that served as suspension mountings and difflock actuators suggests to me that fabrication and design skills among the portal axled fraternity over there was in short supply, and there is no way those vehicles would be competitive against professional outfits from overseas. Bill.

I don't think anyone here wants to turn this forum into a Pirate clone where members regularly engage in flame wars. But I would remind you Jules as Jez has already done that this is a thread on fitting portal axles to various vehicles. Your input so far is just to give reasons or excuses why you can't or won't be going down that road, which is ok, Portals aren't for everyone, and that is why I wrote in an earlier post that you don't ''NEED'' them. This was not intended to be a complimentary observation of your driving abilities, as I don't know anything about the Uk scene. If you really want and ''NEED'' something badly enough you do whatever it takes to attain that goal. In my own case I had no money to purchase Volvo , Unimog axles which have an availability rating in Australia one rung above zero.I wanted and ''Needed'' portals badly.I was time rich but money poor, but I had some machining and fabrication skills, and a big old centre lathe, so I decided to make my own portals. There are others that may not have the skills and/or are too busy with family, careers, etc to devote the time and effort to adapt a different set of axles to their favorite vehicle. If their commitment is powerful enough then they find someone and pay them to do it for them, or do as has been previously suggested, forget about LandRover and buy a Volvo. If you have no real interest in Portals, and your posts thus far suggest you don't, what contribution are you making to this discussion? Bill.

I would appreciate that Jez. When we do eventually pull up roots and move back to Vietnam I would like to buy a Gaz 69 (I just like the retro look of them) and build it up using lessons and techniques that I have applied to my LandRover, re gearing, suspension etc. I doubt that the Vietnamese authorities will permit me to bring my Landy with me, but I am just not going to be able to live without portals. PS, I spotted a couple of portal axled Praga 6x6 trucks near Saigon last trip and a lot of 404 Mogs. Some had been patched up fitted with non portalled axles and leaf springs. Probably not too exciting for Europeans, but it was a big deal for me and drove my wife nuts when I would ask her to stop the motorbike every time I spotted anther ''Ugly'' truck. Bill.

Do you know much about GAZ 69 and UAZ 469's Jez ? Over in Vietnam I have seen quite a few of both types fitted Portal type axles of around 3'' drop and a very compact diff. No difflocking mechanism that I could see though. A friend of mine over there reckons he could get me a pair of axles for around US$400.

Jules, with respect I dont think portals are for you ! Maybe a couple of other members have gleaned some useful information from this thread to assist them in making their decision, but I do not think you ''NEED'' them enough. Bill.

Lara, I can't tell what engine or what size tyres you have, but I have never heard of any other vehicle,particularly one with auto trans that breaks so many halfshafts so quickly,even with a welded locked diff unless it has a seriously bent banjo housing or hub spindle (stub axle). Bill.

Volvo and Mog swivel housings bolt onto flanges on the banjo housings in a similar fashion to how LandRover swivel balls bolt onto theirs. to fit Mog portals to Rover housings you need to cut the flanges off Mog housings and weld them onto the Rover housings. The Rover diff must be turned upside down so that the wheels turn in the correct direction. The Mog upper halfshafts will need to be cut and resplined to suit the Rover Diffs. It would be so much easier to track down some Volvo axle assemblies and fit those. Bill.

I don't think 5600 pounds includes the cost of difflocks or housing reinforcement. Bill.

This thread so far has gone to 5 pages in only a couple of days, with over 20 users participating, which suggests a very real and genuine interest in portal technology amongst the members of this forum. Bill.

If your vehicle requires Formula 1 type materials and technology to survive more than one day, may I suggest that the safety margins are quite small, particularly with regard to differentials, cv joints etc, and that stronger diff/axle assemblies from another brand of vehicle might have been a more cost effective solution ? Bill.