Crawler Gears

[zim]

Bill, we don't rate any landrover gear / shaft as strong enough here. God knows how many shafts, R+P and pegged diffs we've destroyed.

G

[bill van snorkle]

Bill, we don't rate any landrover gear / shaft as strong enough here. God knows how many shafts, R+P and pegged diffs we've destroyed.

G

Well Zim, I don't disagree, but With HBH claiming outstanding results with pegged Rover diffs, and others with 4.75 CWP's, it would appear in the UK at least, you and your associates are more the exception than the rule. Maybe Hampshire has terrain more akin to what we have in OZ ?

[Mr Noisy]

I think on the whole part UK drivers are not using the vehicles very hard.

We do not have a decent aftermarket for replacement axles for land rovers, frankly they aren't needed for the vast majority.

But for us, 37" is huge and 200bhp is loads

Small figures compared to other 4x4 scenes.

[bill van snorkle]

I think on the whole part UK drivers are not using the vehicles very hard.

We do not have a decent aftermarket for replacement axles for land rovers, frankly they aren't needed for the vast majority.

But for us, 37" is huge and 200bhp is loads

Small figures compared to other 4x4 scenes.

The standard issue stuff, aside from the transfercases and some gearboxes is marginal with 31" tyres and 100 bhp in some of the conditions over here.

[FridgeFreezer]

I think on the whole part UK drivers are not using the vehicles very hard.

I'd disagree with that, the challenge scene seems at times to be a challenge to see who can break the most stuff! You're right though, these days it's tweaked TDi's and maybe 36" tyres running in low-traction terrain, a far cry from some of the big-block-V8 bouncing up boulders that the yanks do. There's also the fact that distances are short and speeds are low here, because we don't have the space!

[LowRanger]

The standard issue stuff, aside from the transfercases and some gearboxes is marginal with 31" tyres and 100 bhp in some of the conditions over here.

Hahahahaha I would love 100bhp.That is the sort of thing you dream about with a 200tdi

[LowRanger]

I'd disagree with that, the challenge scene seems at times to be a challenge to see who can break the most stuff! You're right though, these days it's tweaked TDi's and maybe 36" tyres running in low-traction terrain, a far cry from some of the big-block-V8 bouncing up boulders that the yanks do. There's also the fact that distances are short and speeds are low here, because we don't have the space!

In Australia,I think we are somewhere in the middle.The comp scene is usually big HP and big wheels,but the general 4wd scene on the east coast in particular is mainly vehicles with up to 35" tyres and relatively standard engines,maybe tweaked with tuning or a turbo.The terrain is usually sandstone or shale and low traction due to the crumbly nature,unlike the US where it is usually hard rock/granite which is a High traction material,which really opens itself to the High HP extra large wheel buggy brigade.

[Snagger]

OK, guys, you've convinced me. The idea of not increasing the number of components or complexity appeals to me for an expedition vehicle, but for a challenge or play thing I can see your arguments. As always, a lot comes down to the specific use and location of the vehicle, but I can't imagine standard diffs are stronger than KAM or Ashcroft 4.7s, even though they are stronger than the original LR 4.71s. I still think those after-market diffs with a high ratio transfer gear is stronger than standard diffs with underdrive down tot he same final ratio - the diff ratios are doing the work for you, not the underdrive, so the transfer box, prop shafts and diff pinions carry less load than with standard diffs. The half shafts are going to take the same load regardless, but everything else can turn more easily and you have fewer moving parts to worry about. The big thing is the flexibility of bridging the gap between high and low - the diff and transfer box give a wide gap, while the underdrive does give a nicer spread of four different ranges.

[LowRanger]

OK, guys, you've convinced me. The idea of not increasing the number of components or complexity appeals to me for an expedition vehicle, but for a challenge or play thing I can see your arguments. As always, a lot comes down to the specific use and location of the vehicle, but I can't imagine standard diffs are stronger than KAM or Ashcroft 4.7s, even though they are stronger than the original LR 4.71s. I still think those after-market diffs with a high ratio transfer gear is stronger than standard diffs with underdrive down tot he same final ratio - the diff ratios are doing the work for you, not the underdrive, so the transfer box, prop shafts and diff pinions carry less load than with standard diffs. The half shafts are going to take the same load regardless, but everything else can turn more easily and you have fewer moving parts to worry about. The big thing is the flexibility of bridging the gap between high and low - the diff and transfer box give a wide gap, while the underdrive does give a nicer spread of four different ranges.

Throw a set of 4.12 R&P's in and you have an even better setup,not having to worry about the factory R&P detonating.

[bill van snorkle]

Just slap a set of Tibus 4" 1.16 :1 portals on standard 3.54 :1 diffs for a 4.1 final axle ratio. You might need to carry 4 spare output shafts and unit bearing assemblies around with you wherever you go though.

[LowRanger]

Just slap a set of Tibus 4" 1.16 :1 portals on standard 3.54 :1 diffs for a 4.1 final axle ratio. You might need to carry 4 spare output shafts and unit bearing assemblies around with you wherever you go though.

And that is no joke.I personally know that vehicle and its owner is a friend of mine.I just shake my head

[bill van snorkle]

And that is no joke.I personally know that vehicle and its owner is a friend of mine.I just shake my head

Has the output shaft issue been resolved as yet Wayne ? I have put the question to Robert (Oilworker) on 'Expedition Portal' forums, but I think he may be afflicted with a case of selective blindness when it comes to reading posts on his thread, titled " An Expedition Truck On Portals." Having been heavily involved with their development, he either officially or unofficially took it upon himself to publicly promote Tibus's Portal kits, so I don't think me directing concerns over their reliability to him is necessarily out of order.

[LowRanger]

Has the output shaft issue been resolved as yet Wayne ? I have put the question to Robert (Oilworker) on 'Expedition Portal' forums, but I think he may be afflicted with a case of selective blindness when it comes to reading posts on his thread, titled " An Expedition Truck On Portals." Having been heavily involved with their development, he either officially or unofficially took it upon himself to publicly promote Tibus's Portal kits, so I don't think me directing concerns over their reliability to him is necessarily out of order.

The simple answer is NO.I think once again the main difference is the type of use that the vehicles are subjected to,Roberts vehicle is mainly used to travel at speed doing rally type driving,where Iain has his set up as a multi purpose vehicle.As a touring vehicle it worked well,BUT as soon as he has tried to use it on anything challenging,like our afore mentioned sandstone/shale rock steps/boulders,the portals are just not up to the job.The situation has got to the point where they have now been removed from the vehicle.A very expensive learning experience.I did try and advise Iain a long time ago,that there was an inherent design fault and that all the fancy mods that people were advising him to do to the vehicle,wasn't going to rectify the situation,as the Maxi drive portals operate correctly without having to add all sorts of fancy mods.Unfortunately too many people have these fancies about mods,and Iains situation was the perfect opportunity for them to get someone else to build in these mods and see how they worked,without them having to spend any of their own time and money.

[bill van snorkle]

The simple answer is NO.I think once again the main difference is the type of use that the vehicles are subjected to,Roberts vehicle is mainly used to travel at speed doing rally type driving,where Iain has his set up as a multi purpose vehicle.As a touring vehicle it worked well,BUT as soon as he has tried to use it on anything challenging,like our afore mentioned sandstone/shale rock steps/boulders,the portals are just not up to the job.The situation has got to the point where they have now been removed from the vehicle.A very expensive learning experience.I did try and advise Iain a long time ago,that there was an inherent design fault and that all the fancy mods that people were advising him to do to the vehicle,wasn't going to rectify the situation,as the Maxi drive portals operate correctly without having to add all sorts of fancy mods.Unfortunately too many people have these fancies about mods,and Iains situation was the perfect opportunity for them to get someone else to build in these mods and see how they worked,without them having to spend any of their own time and money.

Thanks for the reply Wayne. Is Tibus taking the Portal kit back and refunding Ian his purchase price at least, seeing as they have failed to find a solution to the problem. I'm sure that fitting full floating hubs and broaching out the output gear for a short full float shaft would sort them out, but frankly with only a 16 % portal reduction, It's not worth the effort IMO, because they don't really reduce the stress on the other driveline components like around 1.6:1 for the prototype version on Roberts 130.

[LowRanger]

Thanks for the reply Wayne. Is Tibus taking the Portal kit back and refunding Ian his purchase price at least, seeing as they have failed to find a solution to the problem. I'm sure that fitting full floating hubs and broaching out the output gear for a short full float shaft would sort them out, but frankly with only a 16 % portal reduction, It's not worth the effort IMO, because they don't really reduce the stress on the other driveline components like around 1.6:1 for the prototype version on Roberts 130.

I dont want to say too much more on an open forum at this time Bill,as things are a bit testy and under negotiation,and yes I agree that it requires full floating hubs and shaft as a minimum to sort ot out.There was 2 variant initially offered with different ratios and different drop heights,but I think that there is only the one available now.

[uninformed]

The simple answer is NO.I think once again the main difference is the type of use that the vehicles are subjected to,Roberts vehicle is mainly used to travel at speed doing rally type driving,where Iain has his set up as a multi purpose vehicle.As a touring vehicle it worked well,BUT as soon as he has tried to use it on anything challenging,like our afore mentioned sandstone/shale rock steps/boulders,the portals are just not up to the job.The situation has got to the point where they have now been removed from the vehicle.A very expensive learning experience.I did try and advise Iain a long time ago,that there was an inherent design fault and that all the fancy mods that people were advising him to do to the vehicle,wasn't going to rectify the situation,as the Maxi drive portals operate correctly without having to add all sorts of fancy mods.Unfortunately too many people have these fancies about mods,and Iains situation was the perfect opportunity for them to get someone else to build in these mods and see how they worked,without them having to spend any of their own time and money.

Or maybe some were just trying to help.

[abraded]

Dredging an old thread back up as I'm trying to find some background on underdrive versions. Just stumbled across an older used underdrive to possibly buy. From pictures the attachment of the inner shaft to the planetary gear is different than other versions I have seen. The inner shaft is welded to the gear rather than a splined interface (attahced pic of example of unit like this disassembled on bench). I emailed Ashcroft and Dave wasn't sure this was a solution they had used or if it had been modified after sale at some point. Anyone seen something similar?