bill van snorkle Posted November 24, 2013 Share Posted November 24, 2013 As above. If so, how are they holding up? Recently read a post on another forum where a bloke in OZ has had output shaft failure issues. John, AKA Bush65 on this and other forums, has identified a design fault with the integrated bottom output gear/shaft and I was wondering if the incidence of failure is common. Quote Link to comment Share on other sites More sharing options...
Michele Posted November 24, 2013 Share Posted November 24, 2013 My friend Robert had the very first set fitted to his 130, so far so good and he covered a lot of Km...IIRC the latest version is different. Do you have a link for the shaft failure? Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 25, 2013 Author Share Posted November 25, 2013 Hi Michele. With due respect to Robert (OilWorker) most of the photos he posted on various forums didn't really show the vehicle in what could be described as extreme terrain, just mainly high speed distance stuff. The thread on the shaft failure is on the 'technical chatter' forum on Aulro around 11 November the last post. Owners username is Chook. Quote Link to comment Share on other sites More sharing options...
Michele Posted November 25, 2013 Share Posted November 25, 2013 Sure it's built for overlanding rather than extreme challenge, but he's the only one I know with a set I'll check Chook's thread Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 25, 2013 Author Share Posted November 25, 2013 but he's the only one I know with a set It's a shame there hasn't been more interest in them from the LandRover fraternity. Price seems more than competitive with Marks Adaptors Portals. Design fault of shaft could be relatively easily sorted by going to full floating hubs with a free wheel hub option. Not keen on the piddling 1.16:1 ratio though. They should have kept the 1.6:1 option. Quote Link to comment Share on other sites More sharing options...
elbekko Posted November 25, 2013 Share Posted November 25, 2013 This thread Bill? http://www.aulro.com/afvb/members-rides/85537-chooks-defender-110-a-61.html Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 25, 2013 Share Posted November 25, 2013 £10K still seems like a lot for a set of axles... Do they not do the 1.6 option any more? It's still on the site. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 25, 2013 Author Share Posted November 25, 2013 £10K still seems like a lot for a set of axles... Do they not do the 1.6 option any more? It's still on the site. The last post I read by Robert (oilworker) was that Tibus had discontinued the 1.6 option, IIRC due to them requiring special rims. The 1.16 ratio IMO doesn't really sufficiently reduce the strain on ring and pinions, halfshafts, CV joint etc to compensate for running the 35-37" tyres that anyone wanting portals would use. 10,000 quid does now seem a lot. Last year when the foreign exchange rate to the Australian dollar was very favourable the portals were competitively priced against Marks Adaptors Nissan Portals or Maxidrive Portals that preceeded them but no longer available. Not that I could personally afford any of those options, but if my financial situation was such that I could afford to buy say a new Patrol or Landcruiser, then the percentage increase in cost by adding portals would probably not be all that painful. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 25, 2013 Author Share Posted November 25, 2013 This thread Bill? http://www.aulro.com/afvb/members-rides/85537-chooks-defender-110-a-61.html It seems you have to be a registered member of Aulro to access that link Elbekko. I just found the thread via conventional channels. Quote Link to comment Share on other sites More sharing options...
Michele Posted November 25, 2013 Share Posted November 25, 2013 I guess I'll have to take a day off to go through the whole thread...! Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 25, 2013 Share Posted November 25, 2013 10,000 quid does now seem a lot. Last year when the foreign exchange rate to the Australian dollar was very favourable the portals were competitively priced against Marks Adaptors Nissan Portals or Maxidrive Portals that preceeded them but no longer available. Agreed, especially as Ashcroft were doing sets of full custom axles (albeit non-portal) for £9K IIRC. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted November 25, 2013 Share Posted November 25, 2013 I guess I'll have to take a day off to go through the whole thread...! Shorter thread here: http://www.aulro.com/afvb/technical-chatter/185710-portals.html Quote Link to comment Share on other sites More sharing options...
Nigelw Posted November 25, 2013 Share Posted November 25, 2013 Not sure I see any advantage of running a semi floating hub over a fully floating hub considering the application of the portal boxes! I think they are cheaper to produce too due to the lacking hardware on there in terms of stub axles and fully floating shafts. Not sure I like the idea of losing a wheel coz I hit the loud pedal at the wrong moment! Quote Link to comment Share on other sites More sharing options...
Daan Posted November 26, 2013 Share Posted November 26, 2013 10 k does seem reasonable to produce 4 off portal boxes with 4 off special cut gears each, the shafts, boxes etc, while still trying to make money. I wouldn't want to be in the bussines of making them for that money myself to make a living to be honest. On the side of the buyer though, having spend 10k, I would be rather hacked off seeing these problems, it looks he busted the front and the rear, just with a set of 35s? Daan Quote Link to comment Share on other sites More sharing options...
Team Idris Posted November 26, 2013 Share Posted November 26, 2013 I can see why they did it, but that was a tad optimistic. The idea of fully-floating is that the strength comes from the outer diameter of the tube stub. Sure there's a big drilling up the middle, but in terms of leverage and drive the centre bit of shaft does nothing but add weight. Is this axel the compromise to take a standard rim? I saw the same failure on a side-by-side at a comp the other day. It has to be a big old shaft to do the drive and support the truck + impacts. I'll stick with my prediction, that for ground clearance you're hard pressed to beat big tyres, a small diff and epicyclic hubs. It's the future Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 26, 2013 Author Share Posted November 26, 2013 I'll stick with my prediction, that for ground clearance you're hard pressed to beat big tyres, a small diff and epicyclic hubs. It's the future I would agree with you after recently noticing some new Mercedes 4x4 trucks where the diff centre is barely larger in diameter than the axle tubes. Epicyclic hubs are very heavy though, and I suspect there may be a heat dissipation problem when used at speed,going by what I read some years ago of Mercedes experience with truck racing. My portals barely get above ambient temperature on longer runs in our generally warm climate. The main advantage with full floating hubs, aside from the safety factor IMO is that it allows the halfshaft to be designed correctly for torsional flex with minimal stress risers. The Tibus design of a one piece gear output shaft assy is cheaper to produce, but torsional flex cannot be designed into a shaft that has significant and abrupt changes in diameter, and that is also expected to both drive and support the vehicles weight.Full floating hubs though do add significantly to the weight of a portal assembly and I was very attempted to adopt semi floating shafts when I built my portals. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 28, 2013 Share Posted November 28, 2013 for ground clearance you're hard pressed to beat big tyres, a small diff and epicyclic hubs. It's the future I´ve allways dreamed with some wheel rims with built-in reduction hubs. With a set of those, vehicle´s gearing will not need modification in any way for using super big tyres. It will be the perfect setup for using small tyres monday to friday and BIG ones for the weekend. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 28, 2013 Author Share Posted November 28, 2013 I´ve allways dreamed with some wheel rims with built-in reduction hubs. With a set of those, vehicle´s gearing will not need modification in any way for using super big tyres. It will be the perfect setup for using small tyres monday to friday and BIG ones for the weekend. Years ago I began narrowing down a set of Albion/Leyland truck Epicyclic hubs to use on a LandRover fitted with 101 Salisbury diffs. The hub ratio was 4:1 when the gear on the halfshaft was engaged with the 3 planetary gears, but I was modifying the halfshaft gear (sun gear) so that I could withdraw it from engagement with the planet gears and lock it directly to a drive flange on the outer end of the hub for direct drive. The idea was to run the hubs in direct drive on 36" tyres through the Salisbury 4.7:1 ratio for as you say, Monday to Friday, and for those times when I wanted my own interpretation of a Forest Rover I would engage the planetaries for a total axle ratio of 18.8:1 when running 11.00x28 (50"dia) tractor tyres. Unfortunately before I was able to complete all 4 hubs a scrap metal thief nicked everything and it's probably all been transformed into Chinese refrigerators. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 28, 2013 Share Posted November 28, 2013 Bill - no fair, I thought of that idea last week! I was pondering if you could modify a free-wheeling-hub type of mechanism to bring the epicyclic reduction in/out giving you extra lowness when off-road, and the reduction in loads. But then I thought, if you're going to that effort, why not go a bit further and make it a portal? Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 28, 2013 Author Share Posted November 28, 2013 Bill - no fair, I thought of that idea last week! I was pondering if you could modify a free-wheeling-hub type of mechanism to bring the epicyclic reduction in/out giving you extra lowness when off-road, and the reduction in loads. But then I thought, if you're going to that effort, why not go a bit further and make it a portal? It wasn't an original idea of mine Fridge, they rarely are ! Back in the 1960's 70's over here when Fodens were a popular tractor for pulling outback road trains, they had a similar arrangement of planetary hubs with 2:1 reduction but with a different set of halfshafts that had a drive flange on the end in place of the sun gear. Now these Gardiner engine monsters only had a top speed of 30 mph while pulling a 45 ton payload with the hubs in direct drive.But if the driver was offered an extra loaded trailer to add to the train and was prepared to go slower, he would swap the halfshafts over with a set that had sun gears on the end that engaged with the planetaries and gave the vehicle a payload of 90 tons with a top speed of 15 mph. Actually the low speed wasn't as painful as it may sound because most outback roads back in those days were little more than sand tracks and keeping multiple trailers under control at much over 20mph was difficult anyway. Quote Link to comment Share on other sites More sharing options...
o_teunico Posted November 29, 2013 Share Posted November 29, 2013 "Bolt - on portals" are an inexpensive and sensible alternative to the heavy portal axles of commercial vehicles. Good sense of humor from the TIBUS people! Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 29, 2013 Author Share Posted November 29, 2013 Good sense of humor from the TIBUS people! If they wrote 'relatively Inexpensive' they wouldn't be far off the mark. The most adaptable complete commercial Portal axle assemblies for LandRover sized vehicles are Volvo c303-6 but the availability of these has virtually dried up. Mogs are heavy and wide, the pinions are excessively long and the standard offsets are wrong, and you'd struggle to fit a 16" wheel rim over the drum brakes and keep the scrub radius within legal limits. For most enthusiasts both Volvo's and Mogs require the additional cost of a disc brake conversion. What other easily available commercial axles are there ? Praga's are dirt cheap but too big and heavy, and once again require discs and probably 20" rims which makes suitable, decent lightish weight offroad tyres extremely expensive. Quote Link to comment Share on other sites More sharing options...
henk Posted November 29, 2013 Share Posted November 29, 2013 Dieter from D&G Tuning makes home made 4340chromoly boxes to fit on the pro series chromoly knuckle from www.spidertrax.com. This is a 50degree steering portal axle Quote Link to comment Share on other sites More sharing options...
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