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beavispits

Member Since: 23 Sep 2013
Location: Basingstoke
Posts: 12

2009 Freelander 2 TD4_e XS Manual Lago Grey

Diff modes

I am intrigued by the whole Haldex thing and the various off road modes. I wish I knew what was going on down below.

My old defender had a "gearstick" for locking the centre diff. But as I understand it, the freelander2 has active diffs which slip variable amounts due to the mode selected.

Can anyone fill be in on...

- how many diffs the freelander2 has?
- which are traditional or haldex?
- do the off road modes do anything else apart from tighten the diff binding? eg: throttle response
- what is the difference between M&R/GGS/Sand?

I'm pretty sure Discos have a display of what is locking on the dash...wish mine had that!

Thanks
Scott

16th Jan 2014 10:59 am

BossBob

Member Since: 30 Sep 2010
Location: Bristol
Posts: 1387

2007 Freelander 2 TD4 GS Manual Baltic Blue

Have a look at the recent topic http://www.freel2.com/forum/topic13599.html

16th Jan 2014 11:04 am

pab

Member Since: 28 Aug 2012
Location: Now in Mid-Wales
Posts: 2007

2009 Freelander 2 TD4 XS Manual Lago Grey

Quote:
the freelander2 has active diffs which slip variable amounts due to the mode selected

No, it's not quite like that. The diffs on the FL2 (front and rear - the Haldex is not a diff) are open - no locking and no limited slip. Slip control is done using the brakes and control of power, not via the diffs.

As for the Haldex, that's a clutch (wet plate, multi-plate) which is electronically controlled to vary the amount of torque directed to the rear wheels. Various factors influence torque split, including terrain response mode, road speed, steering angle, wheelspin, etc. Typically (in road mode) torque split is 50/50 when moving off, gradually changing to 90/10-ish as the road speed rises. The Haldex is all about improving fuel consumption on the road, not about the car's dynamics!

As for the TR modes, brielfy:

GGS: 60/40 torque, with a more gradual change to front bias as speed rises. Reduced throttle response. Tight control of wheelspin using brakes and power.

M&R: 50/50 torque. Reduced throttle response. Control of wheelspin, but less so than GGS.

Sand: 50/50 torque (I think). Increased throttle response.

On autos the TR mode also modifies gearchange points.

16th Jan 2014 11:17 am

beavispits

Member Since: 23 Sep 2013
Location: Basingstoke
Posts: 12

Hi thanks for the thorough reply.

I'm surprised...and I have to say a little dissappointed.

There was me thinking I had 3 super dooper active diffs which locked up in various combinations according to the TR mode.

So, just so I'm clear, FL2s have tradditional diffs fore and aft and then a haldex plate clutch active unit in the centre (where the lockable centre diff was on older models). Odd because I had a "locked rear diff" issue a few months ago and people suggested the haldex oil level was low. I assumed this was the rear diff. Even the dealer seemed to agree.

Clever idea using the brakes independantly to control the slip.

I've used M&R mode when greenlaning, but not GGS or Sand yet. Hoping for snow soon!

Scott

16th Jan 2014 12:20 pm

pab

Member Since: 28 Aug 2012
Location: Now in Mid-Wales
Posts: 2007

Quote:
...and I have to say a little dissappointed

Don't be - it all works very well indeed. The FL2 will do far more than most people think.

Quote:
Odd because I had a "locked rear diff" issue a few months ago and people suggested the haldex oil level was low. I assumed this was the rear diff.

That sounds more like the Haldex clutch being engaged when it really shouldn't have been. That would prevent a front/rear difference in wheel speeds, and when turning would give very similar symptoms to a locked diff.

16th Jan 2014 12:36 pm

BossBob

Member Since: 30 Sep 2010
Location: Bristol
Posts: 1387

The limits when you are offroading in an FL2 tend to be gound clearance, (the fuel tank is the lowest point), water depth, or tyres.

16th Jan 2014 2:15 pm

wizking

Member Since: 18 Mar 2010
Location: Around
Posts: 1848

2013 Freelander 2 SD4 XS Auto Indus Silver

You might like to take a look at this @ Beavispits

http://www.awdwiki.com/en/haldex/

16th Jan 2014 3:33 pm

beavispits

Member Since: 23 Sep 2013
Location: Basingstoke
Posts: 12

Amazing stuff. The article mentioned that the haldex goes on the rear axle (where the rear diff normally is) but I'm guessing on a FL2 it replaces the centre diff.

The weird lock up issue was just like driving with the centre diff locked on tarmac. I hired a Jimny on holiday in Greece once and engaged 4wd on-road not realising it had no centre diff. Identical symptoms. Juddery scrubbing on tight corners.

Sounds like my centre haldex had locked up for some odd reason. Hunters checked it over and couldn't find anything wrong and the issue went away a few days after it appeared. I'm wondering if water could've got into the control electronics or something and then dried out. I did go through a ford approx 1ft deep the day before. Well under the max wading depth though.

Scott

17th Jan 2014 3:03 pm

pab

Member Since: 28 Aug 2012
Location: Now in Mid-Wales
Posts: 2007

Correct, the Haldex replaces the centre diff. It is independent of the rear diff, but is physically located on the front of it.

The electronics can misbehave occasionally. Mine once decided the TR should be in M&R mode whether I liked it or not (every time I turned it off it just came back on again). Things eventually returned to normal when I pressed the HDC button. That's computers for you!

17th Jan 2014 3:45 pm

beavispits

Member Since: 23 Sep 2013
Location: Basingstoke
Posts: 12

Aha! That explains why I thought it was the rear diff. I was expecting the centre diff to be just behind the engine like on my old Defender.

Scott

17th Jan 2014 3:55 pm

Aussie Battler

Member Since: 17 Apr 2013
Location: Apsley
Posts: 93

2009 Freelander 2 TD4 SE Auto Stornoway Grey

Take a look at a web site called Green Oval Experience ,they publish a booklet which explains among other things how the TRS system works and how to use these settings efectively .Far more information than in the hand book
Doug

27th Jan 2014 1:10 pm

stevep999

Member Since: 07 Sep 2013
Location: Essex
Posts: 198

56 dollars......ouch

27th Jan 2014 8:10 pm

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