Anderzander Posted April 2, 2014 Share Posted April 2, 2014 As fantastic as it is, the Ashcroft Underdrive is beyond my budget ... So I emailed M R Automotive about the MaxiDrive gears - however they are 1545 aus$ + tax + shipping .... So also quite pricey So, back in Sept last year I emailed Ashcroft to ask if they might consider producing gears and Dave replied to say - nothing in production but looking at it. I've mailed every 3 months since to ask if there was any progress - with the most recent reply saying no plans - just the under drive. So - probably done to death - but is there any other alternative ? I use 1st and 2nd low range and almost never 3rd, 4th, and 5th. So the idea that 3rd becomes say where 5th is - so there is no overlap between low and high range - and you get 2 new lower gears - is hugely appealing, just perhaps unaffordable ? Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted April 2, 2014 Share Posted April 2, 2014 If you can source a good used Borg Warner model 1339 Quadratrac High/ low reduction unit from an Automatic Jeep CJ7 or Wagoneer, I may have a solution for you in the coming months. I won't be offering it commercially, but if the one I'm adapting to an LT230 is successful I will post up details on how to do it and what components need to be made or modified. I have had a 1339 on Wildfings Series Transfercase for the past 15 years, and have also fitted one to the back of an LT95 about 10 years ago with no problems. The LT230 adaption is a little different, and will require a smaller Series drum handbrake or a X type disc handbrake because the 1339 planetary unit is larger than the Ashcroft unit. Quote Link to comment Share on other sites More sharing options...
dirtydiesel Posted April 2, 2014 Share Posted April 2, 2014 Deeper axle gears and a higher transfer box could be your answer. Quote Link to comment Share on other sites More sharing options...
Daan Posted April 3, 2014 Share Posted April 3, 2014 Deeper axle gears and a higher transfer box could be your answer. This. Not sure what you are running now, but 4.75 R&P with 1.2 transfer box, works for me and is pretty cheap by comparison. Quote Link to comment Share on other sites More sharing options...
Anderzander Posted April 3, 2014 Author Share Posted April 3, 2014 Thank you all. Bill - I'd love to hear what you do if you don't mind sharing it with me. Dan and Dann - I'll head over to Ashcrofts calculator and run some numbers. I had sort of overlooked the diffs on the basis that I only wanted to change low range - but it's worth investigating, especially in conjunction with a higher geared high range. I think my naïveté was that there may have been a set of gears from 'such and such' that could be machined to fit. I'm sure though it would be all over the net if it were the case. Quote Link to comment Share on other sites More sharing options...
Ex Member Posted April 3, 2014 Share Posted April 3, 2014 I think the MR auto gears are cheaper if you send them your intermediate gear to be modified. A ratio change in both axles and the diff has got to run over $1000 Australian in parts alone plus a whackload of labour. Quote Link to comment Share on other sites More sharing options...
LowRanger Posted April 3, 2014 Share Posted April 3, 2014 Sell both your kidneys and your first born!!And buy an Underdrive.Once you have driven with one,you wont go back.I have one on my 110 and 1 on my 130 Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted April 3, 2014 Share Posted April 3, 2014 They don't call you LowRanger for nothing! Selectable super low range seems like the ideal way to go, would love one. Quote Link to comment Share on other sites More sharing options...
Anderzander Posted April 4, 2014 Author Share Posted April 4, 2014 Besides the cost of that option - I have the problem of having a hydraulic PTO. So not really an option even with cost aside. Quote Link to comment Share on other sites More sharing options...
Daan Posted April 4, 2014 Share Posted April 4, 2014 ashcroft 4.75 crownwheel & pinion £195 each. 1.2 box = pennies. Just spend a bit of time and you have what you want. Daan Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted April 4, 2014 Share Posted April 4, 2014 I did a bit of maths and even with a 1.003 box, 4.75 diffs would not give me a high enough motorway gear Obviously if this is not a consideration for you, 4.75 is the first port of call then choose your high range accordingly. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted April 4, 2014 Share Posted April 4, 2014 Besides the cost of that option - I have the problem of having a hydraulic PTO. So not really an option even with cost aside. The Borg Warner 1339 planetary box has a PTO spline on the back. That's how I drive my winch, albeit mechanical drive not hydraulic. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted April 4, 2014 Share Posted April 4, 2014 What about the hydraulic underdrive idea? Run a pump from engine or PTO output, use a hydraulic motor to drive back into the transfer box, then you have infinitely-variable low-speed drive. Not perfect, but worth a thought. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted April 4, 2014 Share Posted April 4, 2014 Mr Noisey, I reckon you have your maths wrong..... I might be wrong, but I think you are What tyre size are you running? Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted April 4, 2014 Share Posted April 4, 2014 Only 33" dude I'm pretty sure cos I was originally looking for a 1.003 box and then did some gear ratio checking and found out that 4.1 gears and 1.2 box was the one for me Was a little while ago but that's how it panned out, for some reason Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted April 4, 2014 Share Posted April 4, 2014 The principle was to retain stock disco gearing by the way. Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted April 4, 2014 Share Posted April 4, 2014 In high ratio that is. Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted April 4, 2014 Share Posted April 4, 2014 I seem to remember off the top of my head.... 1.2 t-box and 3.54 diffs = stock 1.4 t-box and 3.54 diffs and 33" tyres = close to stock, but higher low range (obviously) 1.2 t-box and 4.11 diffs and 33" tyres = close to stock, also closer low range to stock 1.0 t-box and 4.7 diffs and 33" tyres = close to stock, but lower low range Just checked, 1.0t-box/4.7/33" is only 80 rpm at 80mph different in fifth. 1.2t-box/4.11/33" is 150rpm higher at 80mph, so not really anything in it Quote Link to comment Share on other sites More sharing options...
Snagger Posted April 4, 2014 Share Posted April 4, 2014 I seem to remember off the top of my head.... 1.2 t-box and 3.54 diffs = stock 1.4 t-box and 3.54 diffs and 33" tyres = close to stock, but higher low range (obviously) 1.2 t-box and 4.11 diffs and 33" tyres = close to stock, also closer low range to stock 1.0 t-box and 4.7 diffs and 33" tyres = close to stock, but lower low range Just checked, 1.0t-box/4.7/33" is only 80 rpm at 80mph different in fifth. 1.2t-box/4.11/33" is 150rpm higher at 80mph, so not really anything in it 1.2 transfer box is for RRs, not Defender. However, using 4.71 diffs (cheaply available and can be converted to 24 spline) with a 1.2 box and 33" tyres would work well, and would be cheaper, more efficient, quieter and more robust and than an underdrive. 1 Quote Link to comment Share on other sites More sharing options...
Bowie69 Posted April 4, 2014 Share Posted April 4, 2014 Yeah sorry, that was in response to Mr Noisy, oops Quote Link to comment Share on other sites More sharing options...
Gremlin Posted April 4, 2014 Share Posted April 4, 2014 Thats how i run mine 1.003 TC and 4.7diffs, low is briliiant. I also know of an lt230 1.4 with maxidrive low gears installed + 1 piece center diff cross for sale, but its here in Malta. G Quote Link to comment Share on other sites More sharing options...
Anderzander Posted April 4, 2014 Author Share Posted April 4, 2014 I'm intrigued - but it's worth more than I could afford to pay for it. Quote Link to comment Share on other sites More sharing options...
bill van snorkle Posted April 4, 2014 Share Posted April 4, 2014 1.2 transfer box is for RRs, not Defender. However, using 4.71 diffs (cheaply available and can be converted to 24 spline) with a 1.2 box and 33" tyres would work well, and would be cheaper, more efficient, quieter and more robust and than an underdrive. What do you mean by "more robust than an underdrive" ? I wasn't aware of any weakness with the Ashcroft underdrive, and I would have thought them to be very much longer lived than any 4.7 ish Rover type diff. Quote Link to comment Share on other sites More sharing options...
Anderzander Posted April 4, 2014 Author Share Posted April 4, 2014 My figures on the Ashcroft site came out as: 3.54 diff 1.4 LT230 Low first: 43.40:1 giving 10mph at 4709 rpm Fifth high: 03.84:1 giving 70mph at 2919 rpm 3.54 diff 1.2 LT230 Low first: 43.40:1 giving 10mph at 4709 rpm Fifth high: 03.33:1 giving 70mph at 2530 rpm 4.75 diff 1.2 LT230 Low first: 58.28:1 giving 10mph at 6318 rpm Fifth high: 04.47:1 giving 70mph at 3394 rpm This is with 31" tyres. The first change obviously just showing the in improved road manners with the disco box. The different diffs put low box nicely down: 3.54 & 1.2 1 43.40:1 2 25.06:1 3 16.42:1 4.75 & 1.2 1 58.24:1 2 33.63:1 3 22.04:1 But the 70 mph speed is almost 1000 rpm up. Quote Link to comment Share on other sites More sharing options...
Mr Noisy Posted April 4, 2014 Share Posted April 4, 2014 Thanks for that Bowie, but the question is, why did I change my mind and end up looking for 1.2 and 4.1, instead of 1.0 and 4.75?! I had the option! Hmmmm... Quote Link to comment Share on other sites More sharing options...
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