Josh NZ Posted July 23, 2012 Share Posted July 23, 2012 Hey guys. Can anyone tell me what's involved with fitting early Rangie 3.54 diffs into a series 2a? Will it affect my low ratio? I want to buy a pair of full axles and just swap the diffs into them, then put them into my landy so it doesn't get laid up without wheels on it. Any help would be appreciated! Quote Link to comment Share on other sites More sharing options...
secondjeremy Posted July 23, 2012 Share Posted July 23, 2012 Back one is easy, front more difficult. Back - drain, pull half shafts, remove propshaft, remove old diff, fit new, re-assemble. Front you've got to remove the complete swivel/hub. If you're careful as you've only got to disengage the half shafts you may be able to leave the brakes connected. Diffs will affect high and low ratios, and the speedometer which will grossly underread. Quote Link to comment Share on other sites More sharing options...
Julian Posted July 23, 2012 Share Posted July 23, 2012 I'd just swap the diffs, much easier that swapping the axles. Do the rear one first, drive it and see how you like it, then if you don't mind the fact that it probably won't pull the skin of a rice pudding in top (esp with overdrive) then do the front! Julian. Quote Link to comment Share on other sites More sharing options...
Mr Ian Posted July 23, 2012 Share Posted July 23, 2012 0nly other issue is the park brake, because of the diff ration change the park brake looses its effectivness by approx 30% , they were not good to begin with so just be careful where you park.. If you look at the 90 handbrake its a lot biger because of the 3.54 ratio. Regards Ian Ashcroft Quote Link to comment Share on other sites More sharing options...
ejparrott Posted July 23, 2012 Share Posted July 23, 2012 Whats the engine? If its a 2286 forget it. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 23, 2012 Share Posted July 23, 2012 Do the rear one first, drive it and see how you like it With of course the warning not to engage 4x4 at any point when you have a different ratio in the back to the front unless you want to blow the transfer box! Common consesnus seems to be that 2.25 engines will not happily pull 3.54 diffs, V8's and TDi's will. I ran 3.54's and an overdrive in the 109 when it had the 3.9 V8 and it pulled quite happily. Ashcroft transmissions have a gear ratio calculator on their website, it's for exactly this sort of question Quote Link to comment Share on other sites More sharing options...
zim Posted July 23, 2012 Share Posted July 23, 2012 I have 3.54 diff's in my 2a and i like them. However i do have a v8 in it. Coupled with an overdriver it's alright to drive on the motorway G Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 23, 2012 Share Posted July 23, 2012 I'd add that running 3.54's and 7.50 tyres I found low range wasn't quite as low as I'd like on hill descents. Quote Link to comment Share on other sites More sharing options...
Snagger Posted July 23, 2012 Share Posted July 23, 2012 I'd add that running 3.54's and 7.50 tyres I found low range wasn't quite as low as I'd like on hill descents. That's why I fitted SII Suffix B low range gears to my transfer box in preparation for the axle swap - the SII Suffix B gears are about 17% lower than the later gears, which offsets the 35% diff increase to some extent. My ideal would be to use those and the overdrive in conjunction with 3.9 diffs, though. Quote Link to comment Share on other sites More sharing options...
Gareth Dickens Posted July 23, 2012 Share Posted July 23, 2012 I calculated once that putting 3.54's under a series makes the high range about the same as aToyota running 4.1's. This is great if running a low revving V8. Problem is that low range is not that low any more and it all gets a lot worse when fitting bigger wheels. You will also be putting a lot more strain on the gearbox, which didn't start out all that strong. You never mentioned what engine you're running? Quote Link to comment Share on other sites More sharing options...
discomikey Posted July 23, 2012 Share Posted July 23, 2012 i dont find 1st low too bad on decents with 3.54's and 235/80's (same height as 7.50s) also got the overdrive but thats all behind a TDI of course. which has 6,500bhp Quote Link to comment Share on other sites More sharing options...
Snagger Posted July 24, 2012 Share Posted July 24, 2012 i dont find 1st low too bad on decents with 3.54's and 235/80's (same height as 7.50s) also got the overdrive but thats all behind a TDI of course. which has 6,500bhp It's all relative. I found first low too high on the steep track and off-road descents in the Alps with a fully laden 109 with a diesel engine. With a petrol engine, it'd have been far worse (less compression and so less engine braking). 3.54 diffs would have made life really difficult. In fact, it'd have been nice to have installed those SII SuffB low gears before that trip.It's the engine braking effort that concerns me about 3.54 diffs with a Tdi or V8, not the accelerative reduction. The overdrive doesn't cause any trouble because you simply deselect it when lower gears are required. If Roamerdrive ever builds the combined under/overdrive, then this sort of problem would be resolved - very tall high gearing available for cruising and lower than standard low range gears off road (if used with those early low gears and 3.54 diffs), and you could use high 4th under-drive for the steep road hills to be similar to standard 4th. It'd be an extremely flexible set-up. It's a shame it'd be very expensive, but have you seen the price of 3.9 crown wheels and pinions from KAM and the like - the over/underdrive might not be much more expensive than having a new pair of diffs set up with those special ratios, and would be a much better option. Quote Link to comment Share on other sites More sharing options...
discomikey Posted July 24, 2012 Share Posted July 24, 2012 i could see your point about the lack of engine braking. however mine still managed to stop the back wheels and put me through a wall downchanging from 4th to 3rd on a wet day. haha. Quote Link to comment Share on other sites More sharing options...
Snagger Posted July 25, 2012 Share Posted July 25, 2012 i could see your point about the lack of engine braking. however mine still managed to stop the back wheels and put me through a wall downchanging from 4th to 3rd on a wet day. haha. Well, that depends on grip and inertia - if you have plenty of inertia (as you would in 4th) and very poor grip, then the maths will overcome any level of optimism. In my case, I was on dry dirt or shale tracks with plenty of grip already in first low and crawling as the descent started, but the vehicle weight and hill steepness still made the car accelerate so the engine was racing, needing frequent and very cautious brake applications. I think the low ratios swap would be a very useful mod for a lot of people who trial or will be using steep tracks when heavy like me, regardless of engine type and diff ratio... Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 25, 2012 Share Posted July 25, 2012 All this talk of 3.54's plus lower low-ratio gears plus overdrives etc. makes me think about the obvious way to match 3.54 diffs - convert to a 5-speed box & LT230 from a later vehicle, then you have a drivetrain that is perfectly matched, plus much stronger, plus a 5th gear. Quote Link to comment Share on other sites More sharing options...
Snagger Posted July 25, 2012 Share Posted July 25, 2012 But that's too easy! Seriously, though, I'm not keen on the chassis and cab modifications, and I like the feel of using the Series transmission - it is part of the old charm. Quote Link to comment Share on other sites More sharing options...
discomikey Posted July 25, 2012 Share Posted July 25, 2012 All this talk of 3.54's plus lower low-ratio gears plus overdrives etc. makes me think about the obvious way to match 3.54 diffs - convert to a 5-speed box & LT230 from a later vehicle, then you have a drivetrain that is perfectly matched, plus much stronger, plus a 5th gear. yes but whats an old series without its famous red and yellow knobs? Quote Link to comment Share on other sites More sharing options...
Gazzar Posted July 25, 2012 Share Posted July 25, 2012 Yes, that IS the biggest issue of going down the LT230 route. And the plate on the bulkhead becomes useless. Ah, well. Quote Link to comment Share on other sites More sharing options...
ejparrott Posted July 26, 2012 Share Posted July 26, 2012 I'm going LT77 plus Series t'box Quote Link to comment Share on other sites More sharing options...
Josh NZ Posted July 26, 2012 Author Share Posted July 26, 2012 Yeah I'm running a petrol 2286 but I'm considering converting to a 2.6L Holden I6 which would pull a lot happier.. However, I've noted that I will probably need to wait till that conversion comes to fruition. I'm also running 750 tyres (don't lynch me! ) Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted July 26, 2012 Share Posted July 26, 2012 Chassis mods aren't exactly major surgery, cab mods = different shaped hole for the lever, and I have a yellow knob on my LT230 (and will add the red knob when I fit the PTO), plus mine is still RWD on the road and everything. The difference is I can bury my foot on the skinny pedal with the 4.6 and not be greeted by a shower of cogs from underneath. I know, it's far too easy and reliable Quote Link to comment Share on other sites More sharing options...
Snagger Posted July 27, 2012 Share Posted July 27, 2012 I'm going LT77 plus Series t'box I have been told that the Series transfer box is considerably stronger than the LT230. That combination should give you a very tough transmission with minimal alterations - you'd just need to move the engine 4" forwars to accomodate the LT77 and mating kit. That might mean using an electric fan in front of the rad, and perhaps moving the rad itself, but that'd be easier than moving the transfer box aft and making custom props (especially on an 88" - there's not much capacity for shortening the rear prop by 4" there). It should otherwise be straight forward. The fifth gear could be lower than an overdrive, though, even though the box is tougher, quieter and more oil-tight than the Series unit. Quote Link to comment Share on other sites More sharing options...
discomikey Posted July 27, 2012 Share Posted July 27, 2012 i couldnt move my engine 4" further forward if i wanted to. theres less than 1" between my pump pulley and rad! Quote Link to comment Share on other sites More sharing options...
ejparrott Posted July 28, 2012 Share Posted July 28, 2012 Nick, I'm going to be doing it to my project 109, possible the camper 109 as a test bed first, not the 88 - she's staying 4-speed. I'm going to try and do it without moving the engine forwards. I've been lying under The 109 and looking at it, and I think it's doable. With the LT77 modification to fit the series t'box you loose the OD anyway, and I plan to fit an X-brake which I believe will give me space between the back of the t'box and the crossmember thats there. Dunno yet, still more work to be done! Quote Link to comment Share on other sites More sharing options...
Snagger Posted July 28, 2012 Share Posted July 28, 2012 Nick, I'm going to be doing it to my project 109, possible the camper 109 as a test bed first, not the 88 - she's staying 4-speed. I'm going to try and do it without moving the engine forwards. I've been lying under The 109 and looking at it, and I think it's doable. With the LT77 modification to fit the series t'box you loose the OD anyway, and I plan to fit an X-brake which I believe will give me space between the back of the t'box and the crossmember thats there. Dunno yet, still more work to be done! That should work, but watch out for contact between the extended front prop shaft and the bell housing cross member. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.