Yep, radiator change and gearbox oil cooler change is needed. The bottom 6 rows of the radiator had a problem where the rows collapsed, this is where the feed is taken for the gearbox oil cooler.

We had the same symptoms on ours a couple of years back after a full gearbox rebuild and torque converter replacement on a trip back from Cornwall (not towing) and it went into 'cooling mode' about 8 miles from home.

This might be useful:

GEARBOX MODES

http://www.fullfatrr.com/forum/topic20319.html

PaulTyrer

Not tried towing again yet, but one question:I understand the radiator may need changing, but does not the fact that a flow test was done (which proved fine) rule it out? Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

If you have access or own a Faultmate or IID tool you can read the actual gearbox oil temperature. That will give you the best information on the actual temp the oil is running at.

Have a look around the forum as this subject has come up before, it will give you the temperature range it starts doing this sort of stuff  MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

Not necessarily.

It is the bottom 6 rows of the radiator where the takeoff is for the Trans oil cooler. I read on a forum that there was a known problem with a range of VIN numbers on the 4.4V8's where the bottom 6 rows collapsed internally, thus reducing the flow to the trans oil cooler.
Our particular car was in the middle of the range of VIN numbers (2003) so we had the radiator changed, but a few weeks later it went into the cooling strategy again, so we had the trans oil cooler replaced, touch wood its been OK from that point.

@Lenb

Just found this:

Land Rover issued a Technical Service Bulletin in September 2007 for "High Engine Speeds and/or Transmission Shift Problems" which stated :

"The customer may experience high engine speeds and/or transmission shift problems after driving for 25 minutes or longer. There may also be the possibility of the transmission overheat message being displayed on the instrument cluster. High transmission fluid temperatures may be the cause of the problem"

In other words the transmission is selecting 'cooling strategy' mode as the bulk oil temperature has exceeded 140 deg. C.

The fault is caused by a partial blockage in the lower eight tubes of the (engine) radiator which supply coolant to the transmission oil cooler - supposedly caused by "depletion of the coolant corrosion inhibitor".

The bulletin states that it's not possible to clean out the partial blockage and that the radiator must be replaced.

LTB00080 - 15 Aug 2007

VIN Numbers 100042-175505

@PaulTyrer

Thanks for that info

I'll take it for a drive Sat and if it happens again will get it changed under the guarantee. Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

Well took it for a test drive with tin tent on back and it happened again!!! So a new rad tomorrow (today). Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

Changed the radiator and took it for yet another test (towing the tin tent) and this time all ok. Past the point where it went wrong last test and on for another 30 mins driving. Big test will come in Oct when we go down to Bournemouth - so fingers crossed.

Thanks for everyone's help  Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

First of all, so sorry for not updating this! Didn't realise how long it had been since my last post!

Anyway, trip to Bournemouth was not very good vehicle wise, lots of judder etc. - in fact got moaned at by stmbo because I spent so much time researching the problem instead of enjoying holiday.... Oops! Plenty of poor advice out there by those that profess to be experts - so ignoring that and sending off for correct oil (20 litres) on my return I had it changed by my own garage - result!!! No more judder, no more 'humming'

But now another problem has arisen: when pulling away after being stood overnight, I can hear a metallic whirring sound that increases and decreases with engine revs (can't replicate when stationary so not engine). Is this the gearbox also, or transfer box? The best way of describing sound is as a similar sound to enervating starter again (when already running) but not as loud.

Trying to decide if this RR is a 'keeper' or do I move it on before having to spend 000's

Thanks Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

Whirring could be centre propshaft bearing. Worth checking if noise coming from just behind driver seat - you will need a passenger to locate source of sound.
.

Gazellio@

Would the sound 'increase and decrease in pitch' with engine revs if it was propshaft bearing? Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

^ It get louder as you increase speed then stays same to ear as engine revs/road noise starts to cancel it out at speed. Pitch stays same though I think.

Doesn't get louder & louder, clears after a few hundred yards, then doesn't return until after been stood overnight again! Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr

NOT the prop bearing then.

Gearbox? Transfer box?  Current: 2004 Vogue 4.4 V8 - 2004 Discovery 2
Previous: 2000 P38 DHSE - 1995 P38 DT Man - 1990 3.9 SE Classic, 1980 3.5 Classic 2dr