Loss of 4 wheel drive

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You'd probably help yourself to spend some time on Google and YouTube and learn how a differential works. Then specifically the D2.

The D2 has open diffs in the axles and without a centre difflock you have an open in the centre. A normal 4wd system such as in a Series Land Rover or older Jeeps, when you put it in 4wd it locks the front and rear propshafts together so they rotate at the same speed. The centre diff lock does essentially the same thing by locking the front & rear props together.

Without the centre diff lock the front and rear props can rotate at different speeds. But the diff will send power to the axle with least resistance while splitting torque equally. So if one prop is taking all the power the TCS will brake the wheels on that axle to try and force the other prop to rotate.

This works with varying degress of success. Mostly the TCS works way better with the centre diff lock, hence it became available on some D2 models and every model since has either a lockable or limited slip centre diff. Some conditions will make it very hard for the TCS to overcome the load and rotate both axles or all 4 wheels when all 3 diffs are open.

However, should the TCS not be working, then you are in a 1wd vehicle and it will be mostly rubbish off road.

All the ones I saw had CDL so did not realise it was optional, was looking at as new as possible.
 
All the ones I saw had CDL so did not realise it was optional, was looking at as new as possible.
It went through three versions.
the first had the bits in the box but no means of actioning it from the cabin, the second had no bits in the box either, the third version had both bits and a lever etc so it could be actioned by the driver.
You may have seen CDL on the label in front of the gear levers but this was misleading as most didn't actually have a workable CDL.
 
It went through three versions.
the first had the bits in the box but no means of actioning it from the cabin, the second had no bits in the box either, the third version had both bits and a lever etc so it could be actioned by the driver.
You may have seen CDL on the label in front of the gear levers but this was misleading as most didn't actually have a workable CDL.

Well the only D2 I have taken off road myself has CDL, it is on the original sales receipt.
 
Well the only D2 I have taken off road myself has CDL, it is on the original sales receipt.
Never said they didn't exist, but the situation is totally differnet with D2s. And you did say that you were looking at "as new as possible" and that was the end of the run that did more commonly have CDL as buyers could specify it.
This link to a page from Ashcrofts backs up what I said.
 
Never said they didn't exist, but the situation is totally differnet with D2s. And you did say that you were looking at "as new as possible" and that was the end of the run that did more commonly have CDL as buyers could specify it.
This link to a page from Ashcrofts backs up what I said.

I know about it now, but at the time I did not know, just saw the sticker and knob.
 
More annoyed at


Out of stock, now I can afford one
 
More annoyed at


Out of stock, now I can afford one
Is your D2 tuned/mapped or something then?
I have heard that you can use a V8 torque converter the only thing being that you have to convert the V8 4 hole drive plate, to the Disco 3 hole one. Which may well be all these are!

Just read the link and yep that is what they are!
I know some people make up their own.
They do seem to be emphasising that they need to be used on tuned TD5s, which mine isn't so I won't be bothering.
Others may sell them.
Best of luck with it!
 
All the ones I saw had CDL so did not realise it was optional, was looking at as new as possible.
Depends on year. I think the early D2's had the difflock in the transfer box, but no lever to make use of it. There used to be a kit you could buy to add a lever. Middle way through production I think LR also removed the bits from the transfer box. Late models I believe it was optional and might have been standard for some markets. Complete with the lever to engage it.

Image from Google, you can clearly see it is only high/low:
hq720.jpg


Not really sure what LR's thinking was behind the decision. Not sure if it was cost based, trying to make it simpler for the driver with less options/levers or over confidence in the TCS system. Or maybe even just marketing as the Td5 Defenders all had difflock as standard.

The system does work without difflock, but the TCS has to work overtime as it has a lot more to do. Vehicles like the p38 Range Rover or Freelander don't have a centre difflock either, but they both use a form of limited slip centre diff which makes a big difference.
 
More annoyed at


Out of stock, now I can afford one
Would you really want one though?

In the tuning world you normally want higher stall converters for performance. I think the only reason for going for this would be improved lock up and more refinement. Can't see how it would improve performance, I'd expect the opposite.
 
Depends on year. I think the early D2's had the difflock in the transfer box, but no lever to make use of it. There used to be a kit you could buy to add a lever. Middle way through production I think LR also removed the bits from the transfer box. Late models I believe it was optional and might have been standard for some markets. Complete with the lever to engage it.

Image from Google, you can clearly see it is only high/low:
hq720.jpg


Not really sure what LR's thinking was behind the decision. Not sure if it was cost based, trying to make it simpler for the driver with less options/levers or over confidence in the TCS system. Or maybe even just marketing as the Td5 Defenders all had difflock as standard.

The system does work without difflock, but the TCS has to work overtime as it has a lot more to do. Vehicles like the p38 Range Rover or Freelander don't have a centre difflock either, but they both use a form of limited slip centre diff which makes a big difference.
The answer to all the biz of what was fitted when is to be found upthread, post #44. ;) But your comments on the rest of it is interesting. Also I have heard that there could be conflict between the use of CDL and the TC.
If you convert it yourself, which isn't difficult if you have the bits in the box, I understand if you want to use the CDL you are best selecting it before starting the motor to not trouble the TC too much!
 
Would you really want one though?

In the tuning world you normally want higher stall converters for performance. I think the only reason for going for this would be improved lock up and more refinement. Can't see how it would improve performance, I'd expect the opposite.

Because stall speed is higher than maximum torque revs.
 
Is it?

Do you know the exact stall speeds and torque plot for your engine? Lower revs will typically be lower power.
From memory, maximum torque for a D2 TD5 auto is a little below 2000 revs, and the stall speed is about 2600?
BHP is usually at max revs but highest torque is typically for a diesel at about 2k revs.
So it depends on whether by "power" you mean BHP or torque.
 
From memory, maximum torque for a D2 TD5 auto is a little below 2000 revs, and the stall speed is about 2600?
BHP is usually at max revs but highest torque is typically for a diesel at about 2k revs.
So it depends on whether by "power" you mean BHP or torque.
Quick Google and it looks like PEAK torque is more like 2500rpm.

Land_Rover_Defender__25_TD5_2495_cc_2002-2007_122_bhp_Stage_1:__167_bhp__277_lbft.jpg


Defender_puma_tdci_Stage2_dyno_graph_2_2..jpg


Power is power..... ;) There is a clue in the acronym ;) ;)

If performance is what you are after, a higher stall should still give the best performance. A lower stall is going to be more refined, which is what the owner comments suggest on the product page.
 
For a start I said "on a Disco Auto TD5..."
Have now been bothered to look this up.
So on a Disco,
max power (DIN) 101 kW @4200 rpm, (131.3 bhp)
Max torque 315 Nm @1950.
so even max power doesn't occur at max revs, which are (governed) 4850.
and these figures can be found all over LZ as well as other places. So your tuning bod... dunno what they are on about.
Backed up here:

and here
The figures vary a little depending on where you look, but not much. For some reason I cannot get my version of RAVE to open up. Maybe soemone else can.

and I never commented on the benefits of higher or lower stall speed. As I don't much give a toss!
Lock up on the other hand..... yes I would like that to be a bit lower so I get it at normal road speeds in the now lower speed limits to be found all over France!
 
For a start I said "on a Disco Auto TD5..."
Have now been bothered to look this up.
So on a Disco,
max power (DIN) 101 kW @4200 rpm, (131.3 bhp)
Max torque 315 Nm @1950.
so even max power doesn't occur at max revs, which are (governed) 4850.
and these figures can be found all over LZ as well as other places. So your tuning bod... dunno what they are on about.
Backed up here:

and here
The figures vary a little depending on where you look, but not much. For some reason I cannot get my version of RAVE to open up. Maybe soemone else can.

and I never commented on the benefits of higher or lower stall speed. As I don't much give a toss!
Lock up on the other hand..... yes I would like that to be a bit lower so I get it at normal road speeds in the now lower speed limits to be found all over France!
What tuning bod? Are you arguing only with yourself or someone else? 😂
 
Quick Google and it looks like PEAK torque is more like 2500rpm.

Land_Rover_Defender__25_TD5_2495_cc_2002-2007_122_bhp_Stage_1:__167_bhp__277_lbft.jpg


Defender_puma_tdci_Stage2_dyno_graph_2_2..jpg


Power is power..... ;) There is a clue in the acronym ;) ;)

If performance is what you are after, a higher stall should still give the best performance. A lower stall is going to be more refined, which is what the owner comments suggest on the product page.
Those figures are defender, 122bhp
 
Is it?

Do you know the exact stall speeds and torque plot for your engine? Lower revs will typically be lower power.
Just over 3000 rpm

Common with remapped TD5s, needed if going over 170bhp as the small one cannot handle the power.
 
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