help alan Posted November 27, 2007 Share Posted November 27, 2007 Does anyone have a solution to the grearing problem created by fitting unimog axles to a discovery 1. Are there any landrover boxes or different higher ratio transfer boxes that will fit ?. Or are there any other manufacturers gearboxes or transfer boxes that can be adapted. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 27, 2007 Share Posted November 27, 2007 Early Range Rover 3spd auto has a 1.003:1 transfer box. It's what I'm running. Quote Link to comment Share on other sites More sharing options...
pugwash Posted November 27, 2007 Share Posted November 27, 2007 1:1 transfer case from a 3 speed range rover auto with 38" tires gives you good gearing. mated to a ZF4HP22 (4 speed rangie auto), you get 7 distinct and seperate gears with high 4th being a little longer than a range rover 3 spd in high 3rd. low first is somewhere in between low underdrive first and second. 5 speed manual gives even more interesting gearing. alternatively an Atlas transfer case can be setup for pretty much any gearing you fancy, but is a bit of hassle to join to land rover boxes HTH Quote Link to comment Share on other sites More sharing options...
pugwash Posted November 27, 2007 Share Posted November 27, 2007 there are also 2 flavors of 1:1 box, one which is stronger than the other, and i have one of both, unfortunately i don't know which is the strong one and which one is the weak one. Quote Link to comment Share on other sites More sharing options...
help alan Posted November 27, 2007 Author Share Posted November 27, 2007 Early Range Rover 3spd auto has a 1.003:1 transfer box. It's what I'm running. Thanks for the reply, can you tell me what size of tyre you are running, and what top speed you can manage, as I want to keep running mine on the road. Quote Link to comment Share on other sites More sharing options...
help alan Posted November 27, 2007 Author Share Posted November 27, 2007 there are also 2 flavors of 1:1 box, one which is stronger than the other, and i have one of both, unfortunately i don't know which is the strong one and which one is the weak one. Thanks for the info, I would be interested in your 1:1 transfer box if you want to sell one. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 28, 2007 Share Posted November 28, 2007 Thanks for the reply, can you tell me what size of tyre you are running, and what top speed you can manage, as I want to keep running mine on the road. Running 37x12.50R16's although they only measure 35" in reality. With 7.29:1 overall axle ratio my top speed is about 60-70, limited by propshaft balance more than anything as the props are doing the equivalent of 100mph+ if they were in a RR with that transfer box on. Quote Link to comment Share on other sites More sharing options...
bathtub Posted November 28, 2007 Share Posted November 28, 2007 Thanks for the reply, can you tell me what size of tyre you are running, and what top speed you can manage, as I want to keep running mine on the road. I run a 3 speed Auto with a 1.003 {or whatever} tranfer box with 42" Iroks on 404 Unimog axles. It will run at 60mph at around 4k Low range is way too low probably 8mph flat out So i run an Ashcroft underdrive .So in high range with Underdrive engaged it will do about 25mph flat out ! This is not ideal though so i am in the process of getting some ring & pinions made around 25% higher ratio. This will allow me to use all ratios & run the car more cooly & economically on road sections. Well thats the plan anyway. The transfer box is about to get the centre diff removeed & a spool fitted also front & rear wheel drive will be selectable. Hope that helps. Quote Link to comment Share on other sites More sharing options...
GBMUD Posted November 28, 2007 Share Posted November 28, 2007 The transfer box is about to get the centre diff removeed & a spool fitted What is a spool and how does it work? Chris Quote Link to comment Share on other sites More sharing options...
Bull Bar Cowboy Posted November 28, 2007 Share Posted November 28, 2007 What is a spool and how does it work?Chris Its mainly a yank term Chris.............. Spool A spool limits differential rotation to exactly zero. A spool consists of a pinion & ring gear only, the centre is solid, the axle is one piece. A mini-spool is similar, replacing the usual differential centre with a solid piece, retaining the factory axles. Technically a spool is not a differential at all, but is used to achieve a similar effect to an LSD on some street & race cars. taken from here.........http://en.wikipedia.org/wiki/Limited_slip_differential Ian Quote Link to comment Share on other sites More sharing options...
Astro_Al Posted November 28, 2007 Share Posted November 28, 2007 Bathtub - whats the situation on the R & Ps? Are you using Mog centre sections? I guess making a few would reduce the cost, I sometimes hear of people looking to up their gearing - wouldn't mind meself. Al. Quote Link to comment Share on other sites More sharing options...
pugwash Posted November 28, 2007 Share Posted November 28, 2007 Pete, would you not be better off fitting a 4 speed auto, it's got to be easier than having new ring and opinions made up surely? Seeing as all 4 speed autos have a 0.75 or less overdrive gear you gain that 25% straight away? Spool? does this mean you have in effect an LSD as your centre diff- does that have significant advantage over a lockable centre diff? Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 28, 2007 Share Posted November 28, 2007 Spool? Do you mean the Ashcroft 2WD kit? (no centre diff, just RWD or locked?) Al - I didn't think you were using mog centres, or is that for your actual mog? Quote Link to comment Share on other sites More sharing options...
Astro_Al Posted November 28, 2007 Share Posted November 28, 2007 I'm not (no 404 stuff at all). Yes its for (potentially) the mog. Could run less stupid tyres to get reasonable on-road gearing then. Al. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 29, 2007 Share Posted November 29, 2007 No body has yet mentioned the GKN or Rockymountain overdrive unit as a solution to the gearing issue. Bill. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 29, 2007 Share Posted November 29, 2007 Depends what lump you're running, having seen how the GKN handled Dave's TGV lump I'm not sure I'd recommend it on a truck that's driven hard. No idea if the RM unit would cope better (IIRC it's a different design?). Not an option for me as I need the PTO hole for a PTO and as I said, the limiting factor is the prop speed, so diff gearing not gearbox gearing. Quote Link to comment Share on other sites More sharing options...
bathtub Posted November 29, 2007 Share Posted November 29, 2007 No body has yet mentioned the GKN or Rockymountain overdrive unit as a solution to the gearing issue.Bill. R&Ps £1500 per car set approx all i need to do is send them a R&P when i get 5 mins & yes the more the better Overdive !! I run an under drive so i presume thats fck that idea. Plus GKN said it wont take the abuse. 4 speed .If i went down that route i would get a Yank box .But my 3 speed is about as strong as they come with what i have had done to it .The 4 speed they can uprate up will be about the £3k to do plus still wont be as strong. Plus different props etc etc. But who knows ,not me thats for sure i just drive it like i stole it & hope it drives it self on the trailer at the end Quote Link to comment Share on other sites More sharing options...
pugwash Posted November 29, 2007 Share Posted November 29, 2007 4 speed .If i went down that route i would get a Yank box .But my 3 speed is about as strong as they come with what i have had done to it .The 4 speed they can uprate up will be about the £3k to do plus still wont be as strong. Plus different props etc etc. FWIW i have a 4L80e warranteed for 900lb/ft for 3 years (and they'll pay shipping if it goes wrong before that) and it cost much less than £3k- includes a 300m sun gear and main drive, kevlar clutches, full manual valve body, custom TC and a couple of other bits and bobs. Whether it works or not is a question i'm not in a position to answer! Quote Link to comment Share on other sites More sharing options...
GBMUD Posted November 29, 2007 Share Posted November 29, 2007 I have a 4L80e warranteed for 900lb/ft for 3 years (and they'll pay shipping if it goes wrong before that) Jim, I would guarantee it for that period too, not like it gets much stick, is it? Chris Quote Link to comment Share on other sites More sharing options...
Astro_Al Posted November 29, 2007 Share Posted November 29, 2007 R&Ps £1500 per car set approx all i need to do is send them a R&P when i get 5 mins & yes the more the better How much per set if 10 sets are made? Al. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted November 30, 2007 Share Posted November 30, 2007 Depends what lump you're running, having seen how the GKN handled Dave's TGV lump I'm not sure I'd recommend it on a truck that's driven hard. No idea if the RM unit would cope better (IIRC it's a different design?).Not an option for me as I need the PTO hole for a PTO and as I said, the limiting factor is the prop speed, so diff gearing not gearbox gearing. I have an underdrive (Borg Warner Quadratrac adapted to series transfercase PTO hole) with a PtO winch drive unit on back of that. Can you get a PTo adapter for the back of the overdrive units ? I would have thought with portals and minimum suspension lift your propshafts angles would be fairly mild. With the flatter plane my propshafts are running at, my truck cruises with less vibration with 5.58:1 final drive ratio than it ever did with 4.7:1 non portal axles and suspension lift. Bill. Quote Link to comment Share on other sites More sharing options...
bathtub Posted November 30, 2007 Share Posted November 30, 2007 How much per set if 10 sets are made?Al. Will ask next week thanks Peter Quote Link to comment Share on other sites More sharing options...
steve b Posted November 30, 2007 Share Posted November 30, 2007 Hi Pete, I might be interested in a set or two of those as well,so will be watching for further news B) cheers steveb Quote Link to comment Share on other sites More sharing options...
help alan Posted December 5, 2007 Author Share Posted December 5, 2007 1:1 transfer case from a 3 speed range rover auto with 38" tires gives you good gearing. mated to a ZF4HP22 (4 speed rangie auto), you get 7 distinct and seperate gears with high 4th being a little longer than a range rover 3 spd in high 3rd. low first is somewhere in between low underdrive first and second. 5 speed manual gives even more interesting gearing. alternatively an Atlas transfer case can be setup for pretty much any gearing you fancy, but is a bit of hassle to join to land rover boxes HTH Would a ZFHP22 4speed ragie auto box fit directly onto a discovery 1 200DTI or would I need an adapter plate. Quote Link to comment Share on other sites More sharing options...
pugwash Posted December 6, 2007 Share Posted December 6, 2007 I don't know the answer to that i'm afraid alan as i'm a V8 boy at heart. Best person to ask would be BishBosh as he did this very conversion, and will know what he had to do to complete it. Quote Link to comment Share on other sites More sharing options...
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