If you can crawl under the car then turning the VCU (it's the biggest thing for you to grab) back and forward might reveal something.

I'd rather take a big blonde (or brunette, I ain't fussy) to bed for good luck but you do what works for you. :p

Not sure the Mrs would appreciate it tho. :oops:
 
Landy-Pandy said:
. is it safe to assume that the IRD is ok? OR is there something big that i'm missing.
Click to expand...

Do the OWUT as suggested above. Also make sure all tyres are identical (same make, type and size) with least worn on the rear and keep all tyres correctly inflated.
 
Thanks guys.
I've also heard that giving it a run around on the rough stuff and making the VCU work a little can help keep them healthy and stop the fluid from thickening.
Any truth to this?
 
Last edited:
Landy-Pandy said:
Thanks guys.
I've also hears that giving it a run around on the rough stuff and making the VCU work a little can help keep them healthy and stop the fluid from thickening.
Any truth to this?
Click to expand...
There may be opinions on that, but if anyone really knows the answer to that, then they are the VCU Guru.
 
Well now that i have a 4WD system (and assuming the OWUT shows positive) i'll be taking the Hippo on some greenlanes... so i suppose we'll find out. ;)
 
Landy-Pandy said:
Thanks guys.
I've also hears that giving it a run around on the rough stuff and making the VCU work a little can help keep them healthy and stop the fluid from thickening.
Any truth to this?
Click to expand...
Simply driving yer hippo will mix the fluid around the plates int VCU as it slips a bit when int use. If yer leave it int garage on the floor for a year... Then repeatedly turn it using the one wheel up test owut (no turning it other than owut) 30 times... After one full rotation the fluid will be mixed around enough to give continuous owut results with the same time measured, as yer keep testing it.

Years ago mags would tell yer to use it or lose it. This were based on the theory thems who take their Freelander's oft road dun't have VCU problems. Also based ont high yearly mileage owners doing a lot of motorway miles and perceived to have a better chance of VCU problems because of this. Int reality... Thems who do a lot of miles at higher speed turn the VCU more revs per minute than normal low speed residential driving. So it's working (slipping) a bit harder per minute than normal due to more turns per period of time measured.

Rule of thumb... Test yer VCU with the owut regular to get a feel for the time every 200 or 500 miles. This will tell yer if it's changing. Then test it every one, two or three thousand miles to make sure the time dun't rise. If it does then test more often to see if it's starting to fail. If it is then take it oft and replace.
 
Hippo said:
Simply driving yer hippo will mix the fluid around the plates int VCU as it slips a bit when int use. If yer leave it int garage on the floor for a year... Then repeatedly turn it using the one wheel up test owut (no turning it other than owut) 30 times... After one full rotation the fluid will be mixed around enough to give continuous owut results with the same time measured, as yer keep testing it.

Years ago mags would tell yer to use it or lose it. This were based on the theory thems who take their Freelander's oft road dun't have VCU problems. Also based ont high yearly mileage owners doing a lot of motorway miles and perceived to have a better chance of VCU problems because of this. Int reality... Thems who do a lot of miles at higher speed turn the VCU more revs per minute than normal low speed residential driving. So it's working (slipping) a bit harder per minute than normal due to more turns per period of time measured.

Rule of thumb... Test yer VCU with the owut regular to get a feel for the time every 200 or 500 miles. This will tell yer if it's changing. Then test it every one, two or three thousand miles to make sure the time dun't rise. If it does then test more often to see if it's starting to fail. If it is then take it oft and replace.
Click to expand...
Thought @dfossil s tests showed that once up to speed the VCU does not slip - his prop counters showed front and rear prop turning at exactly the same rate. It was at slower speeds or cornering or going up hill that the props turned at different speeds.
 
GrumpyGel said:
Thought @dfossil s tests showed that once up to speed the VCU does not slip - his prop counters showed front and rear prop turning at exactly the same rate. It was at slower speeds or cornering or going up hill that the props turned at different speeds.
Click to expand...
It moves very slightly. The chance of weighting, tread depth, air pressure etc being perfect... lot of hair splitting which isn't worth worrying about. I tried the same thing but took values oft the abs sensors.
 
GrumpyGel said:
Thought @dfossil s tests showed that once up to speed the VCU does not slip - his prop counters showed front and rear prop turning at exactly the same rate.
Click to expand...
That must be down to inaccuracies in the speed measurement device.

The front and rear gearing is different, so the VCU must slip in use. Unless the tyres are equalling out the rotational speeds between front and rear, which would mean tyres out of spec.
 
Nodge68 said:
That must be down to inaccuracies in the speed measurement device.

The front and rear gearing is different, so the VCU must slip in use. Unless the tyres are equalling out the rotational speeds between front and rear, which would mean tyres out of spec.
Click to expand...

I think that is the essence of this gearing - the small difference of 0.2% allows perfectly for the difference in weight and hence rolling radius front to rear - any remaining small differences at steady straight line running is soaked up by the fact that we do not have rack and pinion with the tarmac - just four rubber bags of air between the wheels and the road - hence LR hit "The Sweet Spot" with this gearing.
My figures might well be + or _ a rev or two but they are amazingly consistently similar considering they are two independent meters driven off two independent hall effect sensors and magnets.
- and my tyres are matched - in fact I can pick up differences in tyres with the revcounters as I discovered when obliged to use a spare last year.
I can also induce a rev or two difference by putting her at a steep hill flat out on cruise control locked in 4th - the fronts will creep a bit faster - transmitting a bit more drive to the rear due to the torque required to slip the VCU.

All in all I think my Freelander is - given matching tyres - the cleverest thing since sliced bread
 
dfossil said:
I think that is the essence of this gearing - the small difference of 0.2% allows perfectly for the difference in weight and hence rolling radius front to rear - any remaining small differences at steady straight line running is soaked up by the fact that we do not have rack and pinion with the tarmac - just four rubber bags of air between the wheels and the road - hence LR hit "The Sweet Spot" with this gearing.
My figures might well be + or _ a rev or two but they are amazingly consistently similar considering they are two independent meters driven off two independent hall effect sensors and magnets.
- and my tyres are matched - in fact I can pick up differences in tyres with the revcounters as I discovered when obliged to use a spare last year.
I can also induce a rev or two difference by putting her at a steep hill flat out on cruise control locked in 4th - the fronts will creep a bit faster - transmitting a bit more drive to the rear due to the torque required to slip the VCU.

All in all I think my Freelander is - given matching tyres - the cleverest thing since sliced bread
Click to expand...
sweet spot ? its the gearing difference that gives the issue,the reason for the gearing difference is to give the freelander front wheel drive feel
 
jamesmartin said:
sweet spot ? its the gearing difference that gives the issue,the reason for the gearing difference is to give the freelander front wheel drive feel
Click to expand...
I wouldn't totally argue with that - the moment situations require some torque transmitted to the rear the system provides it instantly - hence four wheel drive feel - but in steady straight line running there is minimal load on the IRD so the gearing is about smack on.
 
dfossil said:
I wouldn't totally argue with that - the moment situations require some torque transmitted to the rear the system provides it instantly - hence four wheel drive feel - but in steady straight line running there is minimal load on the IRD so the gearing is about smack on.
Click to expand...
its the difference that means vcu lasts less longer than the range rover vcu with equal 4wd, freelander is a 4wd but supposed to feel more front wheel drive,as soon as vcu stiffens you can feel the wind up in the system through the seat after quite a short distance
 
dfossil said:
I think that is the essence of this gearing - the small difference of 0.2% allows perfectly for the difference in weight and hence rolling radius front to rear
Click to expand...
There is a gearing difference between front and rear, which is deliberate, although not for the common reason given.
dfossil said:
any remaining small differences at steady straight line running is soaked up by the fact that we do not have rack and pinion with the tarmac - just four rubber bags of air between the wheels and the road - hence LR hit "The Sweet Spot" with this gearing.
Click to expand...
Absolutely. The Freelander doesn't have a 50/50 weight distribution. From memory it's about 60/40 biased to the front. This means the front tyres are under a greater load then the rear under normal running. This increased front tyre load will reduce its rolling radius, hence the need for the gearing difference, front to back.
 
Nodge68 said:
Absolutely. The Freelander doesn't have a 50/50 weight distribution. From memory it's about 60/40 biased to the front. This means the front tyres are under a greater load then the rear under normal running. This increased front tyre load will reduce its rolling radius, hence the need for the gearing difference, front to back.
Click to expand...
I don't think there is any 1 reason for any aspect of the Freelander's transmission.

@dfossil s data showed that his Freelander as setup had hit the "sweet spot" - ie with his matching Michelins all pumped to 30psi and traveling at 75mph (on a private road ;)) the LR engineered 0.02% lower gearing to the rear axle was producing a perfect match of 3,097 rpm on both the front and rear props. However, the matching tyres were out of LR spec because there was more tread on the fronts than the rears. They were out of spec by a greater margin than the 0.02% IRD gearing, meaning that if the tyres were in spec the IRD would require a ratio the other side of 1:1 to fix it.

However, on a K Series, with the lighter engine, maybe having more tread on the fronts really does push it way out of the "sweet spot".
 
GrumpyGel said:
However, on a K Series, with the lighter engine, maybe having more tread on the fronts really does push it way out of the "sweet spot
Click to expand...
I suspect the K series sufferers from higher transmission failure, due to the lighter front end.
 
Nodge68 said:
I suspect the K series sufferers from higher transmission failure, due to the lighter front end.
Click to expand...
In my experience the K series is VERY understeery in mondo mode so it probably uses the VCU more then a TD4 or L series.
 
GrumpyGel said:
I don't think there is any 1 reason for any aspect of the Freelander's transmission.

@dfossil s data showed that his Freelander as setup had hit the "sweet spot" - ie with his matching Michelins all pumped to 30psi and traveling at 75mph (on a private road ;)) the LR engineered 0.02% lower gearing to the rear axle was producing a perfect match of 3,097 rpm on both the front and rear props. However, the matching tyres were out of LR spec because there was more tread on the fronts than the rears. They were out of spec by a greater margin than the 0.02% IRD gearing, meaning that if the tyres were in spec the IRD would require a ratio the other side of 1:1 to fix it..
Click to expand...

Actually I did not find that the 1mm difference in tread depth made a measurable difference when swopping tyres around - unlike mixing in a different spec Michelin spare - and I think you need to check your decimal points
 
I've seen on here that there was a change in gearing in the IRD from 2001 onward. Was this from 2001 onward or post 2001 (so 2002 onward)?
I'm just trying to figure out whether mine has the uprated gearing.
And just how much tougher is it than the original gearing?
You're all very helpful by the way, some of these comments make very interesting reading.
Thanks!
 
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