It definitely has its warts, but I prefer having a VCU under the car to a Haldex... in the same way, I'd rather have a D1's locking diff to the D2's reliance on traction control. Having said that, it would be great if it had a warning system for mismatched tyres in the same way various Haldex implementations do.

It is a cheap way of providing four wheel drive. The way the VCU has to be used in this type of system as both a centre diff and a drive component means the VCU is a consumable. It will wear out that is certain. If that wear out is not monitored to ensure it is still functioning as intended it will damage other components. Simple as that.
 
what was correct in saying that a VCU was the means of cheaply implementing 4wd?

Where it is positioned on the Freelander 1. Do you know why it is there and what has to be done to the transmission to make it work? It is a cheap way of converting a front wheel drive transverse engine and gearbox into some sort of four wheel drive. 95% or so of the drive under normal road use goes through the front wheels. Only when they lose traction are the rear wheels properly driven.
 
Where it is positioned on the Freelander 1. Do you know why it is there and what has to be done to the transmission to make it work? It is a cheap way of converting a front wheel drive transverse engine and gearbox into some sort of four wheel drive. 95% or so of the drive under normal road use goes through the front wheels. Only when they lose traction are the rear wheels properly driven.
you are prevaricating, Sir.
Under no circumstances does the VCU implement 4WD. Without an IRD, there would be no 4wd. if the VCU was replaced by a rubber coupling, there would still be 4wd (albeit for a v short time).
 
you are prevaricating, Sir.
Under no circumstances does the VCU implement 4WD. Without an IRD, there would be no 4wd. if the VCU was replaced by a rubber coupling, there would still be 4wd (albeit for a v short time).
your been pedantic, the vcu is the vital component for the front biased 4wd simple system they were after
 
your been pedantic, the vcu is the vital component for the front biased 4wd simple system they were after
I wasnt talking to you. I was answering Wammers specific statement that the VCU " is a cheap way of providing four wheel drive.". it is not and does not! you need to get your facts right. Fitting a VCU does not provide 4wd. It is not in dispute that it is part of the 4wd system.
 
I wasnt talking to you. I was answering Wammers specific statement that the VCU " is a cheap way of providing four wheel drive.". it is not and does not! you need to get your facts right. Fitting a VCU does not provide 4wd. It is not in dispute that it is part of the 4wd system.
i answered in the way wammers seemed to mean it to me,as id read your attempts at proving a pedantic point ,without the vcu it wouldnt be a ird box, it is the facilitator for a cheapish simple front biased 4wd system
 
i answered in the way wammers seemed to mean it to me,as id read your attempts at proving a pedantic point ,without the vcu it wouldnt be a ird box, it is the facilitator for a cheapish simple front biased 4wd system
Yu are, as usual, sticking your nose in where it isnt wanted. Not only that you cant even read properly. All you are doing is supporting an incorrect answer.

You are a one man Hemorrhoid!
 
you are prevaricating, Sir.
Under no circumstances does the VCU implement 4WD. Without an IRD, there would be no 4wd. if the VCU was replaced by a rubber coupling, there would still be 4wd (albeit for a v short time).

You clearly don't know what you are talking about. The transaxle or IRD provides what is in effect a PTO for the rear wheels. The VCU provides a link between that and the rear axle. It has to act as both a centre differential to absorb rotational differences front to rear, also as a drive for the rear axle when required. Until you understand what you are talking about it is best to keep quiet.
 
You clearly don't know what you are talking about. The transaxle or IRD provides what is in effect a PTO for the rear wheels. The VCU provides a link between that and the rear axle. It has to act as both a centre differential to absorb rotational differences front to rear, also as a drive for the rear axle when required. Until you understand what you are talking about it is best to keep quiet.

Doesn't change anything. The VCU is essential to how the system works but is nothing more than a variable slip diff.

Drive is provided by the IRD. To say it merely provides a pto drive is nonsensical.....so does a transfer box.
 
Doesn't change anything. The VCU is essential to how the system works but is nothing more than a variable slip diff.

Drive is provided by the IRD. To say it merely provides a pto drive is nonsensical.....so does a transfer box.

Transfer box and IRD are not the same thing. A transfer box has a centre diff and VCU. The Freelander 1 only uses a VCU to do both functions. Using a VCU as the Freelander does means there is very little drive to the rear wheels under normal use. ONLY when the front wheels lose traction is the rear axle properly driven. In order to have the VCU excited enough to provide drive to the rear axle almost instantly, so that the front wheels don't bog down before rear drive is available. The front propshaft is engineered to rotate slightly faster than the rear one to keep the VCU exited so the drive delay when the fronts lose traction is minimal. In a transfer box application the drive is constantly 50/50 to both axles.
 
Transfer box and IRD are not the same thing. A transfer box has a centre diff and VCU. The Freelander 1 only uses a VCU to do both functions. Using a VCU as the Freelander does means there is very little drive to the rear wheels under normal use. ONLY when the front wheels lose traction is the rear axle properly driven. In order to have the VCU excited enough to provide drive to the rear axle almost instantly, so that the front wheels don't bog down before rear drive is available. The front propshaft is engineered to rotate slightly faster than the rear one to keep the VCU exited so the drive delay when the fronts lose traction is minimal. In a transfer box application the drive is constantly 50/50 to both axles.

yet again it is you posting lies and mis-truths. Point out to me on any defender or discovery transfer box where the VCU is?
 
Transfer box and IRD are not the same thing. A transfer box has a centre diff and VCU. The Freelander 1 only uses a VCU to do both functions. Using a VCU as the Freelander does means there is very little drive to the rear wheels under normal use. ONLY when the front wheels lose traction is the rear axle properly driven. In order to have the VCU excited enough to provide drive to the rear axle almost instantly, so that the front wheels don't bog down before rear drive is available. The front propshaft is engineered to rotate slightly faster than the rear one to keep the VCU exited so the drive delay when the fronts lose traction is minimal. In a transfer box application the drive is constantly 50/50 to both axles.

I know that but it STILL doesn't change anything.

For 4wd the drive must split to both the front and back wheels.

The splitting of the drive is done by the IRD, the fact that the split drive isn't equal is neither here nor there.
 
yet again it is you posting lies and mis-truths. Point out to me on any defender or discovery transfer box where the VCU is?

Now come on MHM get a grip. I wouldn't think there is a VCU on the transfer boxes of a type 45 destroyer either. You can be educated if you listen, if you want to play the fool. Carry on in ignorance.
 
Now come on MHM get a grip. I wouldn't think there is a VCU on the transfer boxes of a type 45 destroyer either. You can be educated if you listen, if you want to play the fool. Carry on in ignorance.
So - educate me - which Landrover transfer boxes have a VCU then, except for your beloved Rangie?
 
I know that but it STILL doesn't change anything.

For 4wd the drive must split to both the front and back wheels.

The splitting of the drive is done by the IRD, the fact that the split drive isn't equal is neither here nor there.

The IRD provides a drive output for the rear axle that is not disputed. How the drive is treated after it leaves the IRD is the critical point.
 
The IRD provides a drive output for the rear axle that is not disputed. How the drive is treated after it leaves the IRD is the critical point.
no it is not - you stated that it was the VCU that gave the freelander 4wd - you are wrong.
 
Ah...it's a meaningless argument about terminology and nothing at all to do with anyone's understanding of how the system works.
 
I know that but it STILL doesn't change anything.

For 4wd the drive must split to both the front and back wheels.

The splitting of the drive is done by the IRD, the fact that the split drive isn't equal is neither here nor there.
obviously you need to split drive and there are many types of system they could have used ,s3 type for instance ,vcu is what makes the system they used on the fl
 

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