Defender transfer case gear up 1.41. to 1.22

[simmo]

My apologies gentlemen and ladies, I did try a search on this "transfer case gears", but couldn't find anything on it.
I'll be fitting a Mad Man VNT turbo kit in June, and looking at the torque curves I'm going to have a lot of extra torque up to 3000 rpm, so I want more relaxed cruising at 100 km/hr. I toyed with the idea of a roverdrive overdrive , but it's expensive & and added complication. I 've read somewhere, I think quite few of you have changed your TC gears to the higher ratio 1.22, from the discos.
I'd like to do the same, did you just change the gears or did you change the whole T box? My preference is to change the whole box. Another member has a T-C from a disco 2 for sale. has anyone a similar experience using the disco 2 transfer case? I figure we could have a quick look inside at the center diff to makes make it's Ok. and them put it straight in.
Its amazing how the project has budget "creep" or " growth". but after 15 years I don't mind spending a bit on her. say $2200 for the kit landed, xxx$$ for the transfer case + labor fitted, $600 for some exhaust mods. ( it will be the car the TDi should have been by 1995 :o). My guess is we're going to not have a lot of beer money left from $4000. But for me It's good to have an offroad car you can use and not loose sleep over dirt, water, dust etc.
So I appreciate your advice about the project, I''l keep you updated about how the budget is going. cheers simmo.:cool:

[redrovertdi]

Make sure that disco 2 transfer case has a centre diff lock?, i fitted the whole disco transfer case to my 95 110 after converting to auto, no regrets here

[85 county]

My apologies gentlemen and ladies, I did try a search on this "transfer case gears", but couldn't find anything on it.
I'll be fitting a Mad Man VNT turbo kit in June, and looking at the torque curves I'm going to have a lot of extra torque up to 3000 rpm, so I want more relaxed cruising at 100 km/hr. I toyed with the idea of a roverdrive overdrive , but it's expensive & and added complication. I 've read somewhere, I think quite few of you have changed your TC gears to the higher ratio 1.22, from the discos.
I'd like to do the same, did you just change the gears or did you change the whole T box? My preference is to change the whole box. Another member has a T-C from a disco 2 for sale. has anyone a similar experience using the disco 2 transfer case? I figure we could have a quick look inside at the center diff to makes make it's Ok. and them put it straight in.
Its amazing how the project has budget "creep" or " growth". but after 15 years I don't mind spending a bit on her. say $2200 for the kit landed, xxx$$ for the transfer case + labor fitted, $600 for some exhaust mods. ( it will be the car the TDi should have been by 1995 :o). My guess is we're going to not have a lot of beer money left from $4000. But for me It's good to have an offroad car you can use and not loose sleep over dirt, water, dust etc.
So I appreciate your advice about the project, I''l keep you updated about how the budget is going. cheers simmo.:cool:

my thoughts are ,
you need torque after cruising speed to manage slight inclines etc. it not a racing car where you gear to max HP

a VNT is not going to add oodles of power. add to that the turbo will only be adding power as you add fuel. so a cruse she will not be producing what you map is saying, that’s hammer down stuff.

on the other hand. Staying in 5th gear is not smart for a 380, dropping down to 4th is smart

300 tdi have enough problems in first gear when loaded. You will be moving that up as well

[uninformed]

Agree with 85 County. I have the 2.8gtv engine in my 110 tray back. No way would I go taller high range. And yes I do run stock diff gears and stock size tyres.

[simmo]

a VNT is not going to add oodles of power. add to that the turbo will only be adding power as you add fuel. so a cruse she will not be producing what you map is saying, that’s hammer down stuff.

The proposed TC has a a center difflock-TKs.
The real attraction for me is the reduction in revs from about 3200 to 2800 at 100 kms /hr. Should be quieter and better fuel consumption.

I take your point about 1st gear is under more load, it's something I have to keep in mind, I usually change to low range if a lot of torque is required in 1 st gear. I've heard rumor about a weakness of 5th gear, but I towed a trailer with a series one for a few hundred kilometers on a about 40 deg day. Having said that I have a transmission cooler in my garage to fit:o thanks for your advice simmo

[rijidij]

I went to 1.22 from 1.41 and it's much more pleasant at cruising speeds. I swapped the whole TC because I was lucky to get one as a spare when I bought the 130.
I have a Garrett VNT, Alisport intercooler and Alisport radiator. Admittedly, mine is fuelled up quite a bit, but it will accelerate up those long inclines in 5th gear rather than struggling up them.

Cheers, Murray

[85 county]

but it will accelerate up those long inclines in 5th gear rather than struggling up them.

Cheers, Murray

now why would you want do risk that??

[eddy]

I have a TD5 110 Defender which I had converted to 1.2 ratio using the kit from Ashcroft's.The independent Land Rover mob that did the conversion had three goes at it before they got it right[had to call in the local expert Maurie Urquhat]Even then they baulked at fitting the one piece cross pin.If I did it again would definitely look for a Disco2 box with diff lock.Make sure you change all the oil seals and the intermediate gear O ring before fitting.
The higher gear makes for easier touring,quieter/better fuel economy.I have not towed with mine but it could possibly involve more revs when moving off,especially with a 300tdi.

[dero]

It's horses for courses , we put a disco T'case in our 110 300TDI and it goes well on the road , lightly loaded , but struggles with weight .
I would not put one in my 300TDI 130 work ute , even though it has an Alisport VNT & intercooler & fueled up .

[85 county]

ok this is my fear of running to high a gearing with a R380.

you may have the power, but low rpm and a high load, may or may not be better for you but it will not be nice to the R380

the R380 is a 4 speed box with a fith gear stuck on the outside.

its the fith gear that is the issue. high loads for long periods. higher the load for shorter periods and the output shaft gives in.

this is a r380 out of a 130 td5 chiped and towing a caravan.

i had had this discustion with the owner a couple of times and had pointed out his habbit of never shifting down or shifitng back into 4th,

result the high load on the fith gear cluster, lack of good lubrication made worce by low reves, a bit of head and PING there goes your output shaft.

[uninformed]

Plus pushing harder at a lower rpm and staying in 5th will push egt higher.

[simmo]

Thanks you very much guys wizard, ininformed, dero, eddy, 85 county et all.

I just got he benefit of 50 years experience, so i feel i can make an informed decision, thankyou.
I'll go ahead if i can get the D-2 TC, but 85 county's point is well made, about slogging it out in 5th gear at high torque scenario. It's not really my style, a car has a gearbox for a reason so you can keep the engine in comfortable power & torque range, I've been driving small engined cars all my life, ( too stingy to buy something with a big engine). They need some revs to give any sort of power, "if in doubt change down :D" Because I only travel at 100 km/h, if the engine is struggling I can change down to 4 th, with the 1.22 gears it will bump up the revs. The comments of those that have done the conversion are pretty much what i expected, it wont' pull up long hills heavily loaded or with big head winds etc. no problem I'll just go back to 4th. I can tell when the engine is comfortable by the EGTs and the boost pressure. It' s a factor in Australia the distances we travel are fairly big so comfortable cruising for the engine and passengers is important, so steady cruising at 2800 rpm should be good. cheers simmo

[rijidij]

but it will accelerate up those long inclines in 5th gear rather than struggling up them.



now why would you want do risk that??

I do usually throw it back to fourth for the sake of the gearbox, I was just indicating the extra power/torque will easily handle the 1.22 gearing.

Cheers, Murray

[butundede]

I've recently had the TC gears changed from 1.4 to 1.2. I have a Td5, chipped, bigger intercooler, and a VNT from Bell. I'm also running BFG Km2 255/85/16.
I have no problem taking off, even with a 2.5 tonne dual axle trailer, plenty of grunt. If anything it's a bit scary how fast the deefer wants to go now.
100kmh is at 2080rpm and its pleasant to be inside the vehicle. I drive with my egt gauge and the fuel economy whilst fully loaded with camping gear and surfboards on the roof rack, sitting mostly on 110kmh for 7300km from Tassie to western south oz and back averaged 10.6 lt per hundred.
Last year same trip, same amount of gear over 6900km I averaged 12.9, the difference being the VNT and the TC ratio change. Plus when I got home I was sick of the noise of the Td5 revving its ring off.
For me, the TC ratio change and VNT was money well spent, but I only did both because the original turbo popped as did the r380 lay shaft bearing, so while it was out, the vehicle got new clutch, DMF, and ratio change. The gears were from a 08 puma lt230q.

Cheers Bob

[Leyland1980]

My apologies gentlemen and ladies, I did try a search on this "transfer case gears", but couldn't find anything on it. I'll be fitting a Mad Man VNT turbo kit in June, and looking at the torque curves I'm going to have a lot of extra torque up to 3000 rpm, so I want more relaxed cruising at 100 km/hr. I toyed with the idea of a roverdrive overdrive , but it's expensive & and added complication. I 've read somewhere, I think quite few of you have changed your TC gears to the higher ratio 1.22, from the discos. I'd like to do the same, did you just change the gears or did you change the whole T box? My preference is to change the whole box. Another member has a T-C from a disco 2 for sale. has anyone a similar experience using the disco 2 transfer case? I figure we could have a quick look inside at the center diff to makes make it's Ok. and them put it straight in. Its amazing how the project has budget "creep" or " growth". but after 15 years I don't mind spending a bit on her. say $2200 for the kit landed, xxx$$ for the transfer case + labor fitted, $600 for some exhaust mods. ( it will be the car the TDi should have been by 1995 :o). My guess is we're going to not have a lot of beer money left from $4000. But for me It's good to have an offroad car you can use and not loose sleep over dirt, water, dust etc. So I appreciate your advice about the project, I''l keep you updated about how the budget is going. cheers simmo.:cool:

I have an lt230 transfer case sitting in the garage if you are interested pm me, I haven't got round to advertising it yet. It is a runner but a bit worn, perfect for a rebuild.

[simmo]

Some info about the LT 230 & R380 Fyi

[uninformed]

Look at the 5th gear ratio, you can change that according to Ashcroft's i.e. put 5th gear set out of a V8 R380 into a diesel R380. That will gain you a little in lowering the revs.

As for that pdf Simmo, not sure but the rpm doesnt seem right. Im pretty sure my truck is not doing 3406 rpm in 5th at 65mph.

Seems my engine must be leaving a lot on the table compared to other members here. Even if I could get the power out of it to match, I have had enough problems keeping the engine in a safe cool zone towing here in SE Qld.

And not just the extra power adding the heat, but those towing with bigger tyres and the higher gear sets. Thats more engine load.

[Kappa130]

I did the complete disco T/C swap to my chipped, and bigger intercooler TD5 130 dual cab about 40K km's ago.
At the moment Im running 285/75 x 16 tyres and it handles is fine , even when towing my off road Jayco van .
1st gear can be a bit tall when taking off with the loaded van on a hill but it's way better cruising on the highway and noticable quiter in the cab on the highway.
But if change up to 35"s i'll rebuild and fit my old T/C as in my opinion it'll be over geared.

[rick130]

I did the complete disco T/C swap to my chipped, and bigger intercooler TD5 130 dual cab about 40K km's ago.
At the moment Im running 285/75 x 16 tyres and it handles is fine , even when towing my off road Jayco van .
1st gear can be a bit tall when taking off with the loaded van on a hill but it's way better cruising on the highway and noticable quiter in the cab on the highway.
But if change up to 35"s i'll rebuild and fit my old T/C as in my opinion it'll be over geared.

There's no way a Tdi, even with the fuel turned all the way up would pull that gearing in first, high range.

I'd reckon I'd fry my clutch in no time.

IMO the stock 1.4:1 t/case plus 33.3" tyres is about right on the highway while being a pain in first and needing second/low for trailer take offs on hills (or when dead cold)

[simmo]

Hi I have 235/85/16 tires diameter is about 806mm, 31"?, I have a about 2" of suspension lift

33" = 838 ( +3%), 35" ( +10%)

When I go over a deep gulley at an angle, my back wheels can articulate all the way up into the wheel arches and almost touch the underside of the mudgard in side. ( within a couple of millimeters). If your wheels are 2" or 4 " bigger in diameter, and wider as well, do they fit inside the wheel arched when your axle articulates? or do they rub there? simmo

[85 county]

Hi I have 235/85/16 tires diameter is about 806mm, 31"?, I have a about 2" of suspension lift

33" = 838 ( +3%), 35" ( +10%)

When I go over a deep gulley at an angle, my back wheels can articulate all the way up into the wheel arches and almost touch the underside of the mudgard in side. ( within a couple of millimeters). If your wheels are 2" or 4 " bigger in diameter, and wider as well, do they fit inside the wheel arched when your axle articulates? or do they rub there? simmo

lower your bumpstops

[chopper]

Isnt this like putting 235/85's on a disco ?

[simmo]

I just read a step by step instruction on how to change the transfer case done by Les and Tony I think and posted in 2007. Great piece of work, thanks very muchly. Strangely I find the links on the the net not the alro site.:)

[simmo]

Hi, has anyone got a tacho in 300 tdi with an R 380 ? to help verify some of the figures I'm getting off the net.

according to different sources, I get different info. (1995 300 tdi , R380, LT230 1.41, 3.54 diffs)

Ashcroft calculator says T/C ratio 1.41 ; 2520 rpm @ 60mph (100km/hr.) T/C ratio 1.21 ;2150 rpm @ 60 mph

If a defender does 2520 at 100 km /hour i don't think I need to change the ratios that's fairly relaxed revs for the engine anyhow, I rarely go over that speed. I have 31" wheels 235/85/16.

Another source says; TC; 1.41 3650 @ 60mph, :eek: TC; 1.22 2720 @ 60 mph.:eek:

who to believe? many times on the forum Ashcroft Calculator is quoted ,so i'm guessing their figures are the most believable. Can any one back up Ashcroft figures with real life readings? Thanks if you an help. cheers simmo.

[rick130]

There no way on God's green and brown earth a Tdi is doing 3650RPM @ 100km/h.

Calculate it out yourself, easy enough to do.

[uninformed]

There no way on God's green and brown earth a Tdi is doing 3650RPM @ 100km/h.

Calculate it out yourself, easy enough to do.

depends on how much oil you add :D

[justinc]

Hi, has anyone got a tacho in 300 tdi with an R 380 ? to help verify some of the figures I'm getting off the net.

according to different sources, I get different info. (1995 300 tdi , R380, LT230 1.41, 3.54 diffs)

Ashcroft calculator says T/C ratio 1.41 ; 2520 rpm @ 60mph (100km/hr.) T/C ratio 1.21 ;2150 rpm @ 60 mph

If a defender does 2520 at 100 km /hour i don't think I need to change the ratios that's fairly relaxed revs for the engine anyhow, I rarely go over that speed. I have 31" wheels 235/85/16.

Another source says; TC; 1.41 3650 @ 60mph, :eek: TC; 1.22 2720 @ 60 mph.:eek:

who to believe? many times on the forum Ashcroft Calculator is quoted ,so i'm guessing their figures are the most believable. Can any one back up Ashcroft figures with real life readings? Thanks if you an help. cheers simmo.


2520 is correct. 3650 would be for the 1.6:1 ratio with petrol 4 cyl fitted I reckon....?

JC

[pibby]

Defender td5 110 auto with puma transfer 1.2? Tyres 1mm diff diameter to standard.
About 2150rpm 100km/h.

I know not what you're asking exactly but I find once I go over 90km/h the main noise is the wind noise from the windscreen.

[simmo]

Thanks guys I think its about the 2500 to 2700 mark, I guy from SA with a def' says his does 2700 by his tacho, that's close enough to 2520. I'll focus on the Madman turbo installation first. Once I get that sorted, I'll move onto the transfer case. Even without with the original turbo I always felt the Def was a little under geared and often found myself reaching for the gear lever to change another gear. I read people report that the boost pressure was 15 psi at 100 km/hr, must be heavily loaded or towing my def is usually a little less than 10 at 100km/h. I have the 1.21 transfer case almost on the way, just waiting to sort the freight and pick up etc.