I do like seeing things hacked to pieces!


Surprised nobody has tried to fit a Haldex clutch box up in the space where the VCU would be?
 
Always thought it was a good idea to have switchable 4WD on my Freelander for the previously mentioned reasons ( IRD, Diff, Tyres ) but a bit of a job doing it.

Seeing the unit split apart it looks as though it's pretty similar to a multi-plate wet clutch on a bike. It would be nice if you could use a bike release mechanism but pretty sure bike clutch plates wouldn't stand the constant slipping so when you went to use them there would be nothing left.

Very interested to see what you're doing though.

Cheers

Kev
 
I thought about using a bike clutch at first as a simple on / off way of transmitting the drive but I decided it would be too complicated to arrange the release mechanism and I wondered if they would be able to cope with the torque
 
I think Im right in saying that Austin of Bell Engineering has said he has never come accross a VCU that has totally siezed, they just stiffen up which over time is enough to destroy the rear diff &/or the IRD due to the aformentioned diff ratios, I think if you completely locked the front & rear shafts together the first time you forgot to disengage it when grip improved it would damage the IRD / Rear Diff in no time :(
 
I do intend to put a warning light on it like most other 4x4's, I doubt it would get wind up so quickly but I guess I wont know until I find out! lol Little bit of news re "the build" Ive been to see the engineering chappie who was going to stick a few of my bits together and Ive had a slight rethink on some of the parts I'm using so I will need to source some other parts now before I can move forward (just a bit of info for the doubters who may think its "gone quiet" for a while! lol :p )
 
I do intend to put a warning light on it like most other 4x4's, I doubt it would get wind up so quickly but I guess I wont know until I find out! lol Little bit of news re "the build" Ive been to see the engineering chappie who was going to stick a few of my bits together and Ive had a slight rethink on some of the parts I'm using so I will need to source some other parts now before I can move forward (just a bit of info for the doubters who may think its "gone quiet" for a while! lol :p )
Good luck Kev.....I hope you are right ;)
 
Thing is, even in loose conditions, you will get front/rear wheel slippage which will actually loose traction I'd have thought due to the difference in ratios front/rear. Surely a better approach would be to fit a good new VCU and then somehow match the front/rear gearing in the IRD or diff? Once it's 50/50 the VCU should then be as reliable as the old Range Rover.
 
I've missed out on this thread when I've been searching for VCU replacements. How are you getting on?

To those that knock you, just give them a
:mooning:

I like what the VCU does, I don't like the way it does it because of its reliability and inability to detect problems. Who wants to jack a wheel up each week, do a VCU test (that isn't very acurate anyway) and rotate all the tyres. Then find its going to trash your transmission anyway.

My current thinking is to remove the props, vcu & pinions. Replace the IRD pinion with a hydrulic pump and bolt a hydraulic motor onto the rear diff. In the pipework would be valves calibrated to limit the torque to the the rear diff to levels safe enough to not destroy the IRD for on-road use. This would give safe and capable on-road AWD abilities. Then a button on the dash to close the valves for off-road (I do a fair amount of beach driving). I don't know much about hydraulics. I've been reading up and researching, but the only thing I've concluded so far is that hydraulic equipment is expensive!
 
Whatever alternative you find I don't think it will be cheaper.
I had a chat with Titan Motorsport who initially said they could probably do something clutch based, but because of the IRD drive ratio it would probably wear out quicker than we would like.
The alternative they came up with was a locking differential arrangement which would be either locked or free with no middle ground, but that didn't sound too great either!

Personally I'm persuaded by the argument (apologies to whoever first mooted it) that the best direction for development would be a standard VCU combined with a modified IRD with a 1:1 ratio; this should mean a much greater VCU life.
 
well Ive been mad busy at work with inspections and such but I intend to get back on with it before we break up for crimbo!
 
As I keep saying, I think we are going down the wrong route trying to mod the VCU, which isn't really the problem anyway- it's the IRD ratios. Try to find a way to make it 1:1 front:rear and then the VCU won't be a problem so much and even tyres won't cause such an issue. It will be like an old Range Rover. I don;t know how to do it, but someone must know more about the gearing inside the IRD?
 
Being honest, sounds like a total waste of time? The car automatically switches between 2 and 4 wheel drive as and when required anyway, plus with the advent of traction control automatically sends power to whichever wheels have the best traction.

No it don't matey. :rolleyes:
 
Wey just wondering. Coz a few folk remove the prop to avoid the slight advanced wear rate even a good vcu gives, this would do that and mean that when it was locked in it would only be as bad as the state of the vcu, only downside having to machine and mod the clutch into the system :p
 
I've missed out on this thread when I've been searching for VCU replacements. How are you getting on?

To those that knock you, just give them a
:mooning:

I like what the VCU does, I don't like the way it does it because of its reliability and inability to detect problems. Who wants to jack a wheel up each week, do a VCU test (that isn't very acurate anyway) and rotate all the tyres. Then find its going to trash your transmission anyway.

My current thinking is to remove the props, vcu & pinions. Replace the IRD pinion with a hydrulic pump and bolt a hydraulic motor onto the rear diff. In the pipework would be valves calibrated to limit the torque to the the rear diff to levels safe enough to not destroy the IRD for on-road use. This would give safe and capable on-road AWD abilities. Then a button on the dash to close the valves for off-road (I do a fair amount of beach driving). I don't know much about hydraulics. I've been reading up and researching, but the only thing I've concluded so far is that hydraulic equipment is expensive!
my honda hrv has a similar set up and it works fine, pump in the diff when wheels spin up the pressure increases drive the rear...
also worth looking at are the electronic clutch assy on the rear diffs of most modern suv type things, jeep patriot, rav4 etc..but then again may as well buy a newer freelander if you want that system.lol
 
This idea would work but you'd need to retain the VCU, if an electromagnetic clutch could be grafted onto the rear prop in front of the VCU you'd have selective 2/4wd
 

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