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Hi right for all the uk p38 dse/dhse owners who are wondering whether fitting fog lights will have any effect on running in respect to blocking off the gear box cooler i,ve just completed a 440 mile round trip doing 75 on cruise most of the way and about 60 mile on normal a/b roads and my 2.5 dse run like a dream with fogs fitted first time i,ve had it on a run since fitting and like many who have asked the question about will it have a detremental effect on running with no vent on to the cooler my answer would be no it doesnt . mine has had the ecu remapped and returned 27.2 mpg and i,ve still got quater of a tank left not a murmur out of the temp gauge (some on here say it will fry your head )again i,d say no . hope this helps for those of you thinking of doing these mods. neil `8)
 

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Solo driving I would back that up in the UK.

I had the gearbox get warm once - that was towing on a long hill on an exceptionally hot day and even then only at the very top; running down again it soon returned to normal.

That said it was enough for me; especially as I shipped it to SA where we have oh so much nicer weather. I took the lights out (they were not wired in anyhow) and put the grill in place instead. Mind you Cape Town is not known for thick fog mornings anyway.
 

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1995-2002 Range Rover P38A
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The auto box on my chipped DSE does run hot.
Solo driving you would probably get away with it but towing in hot weather is another matter.
I have had the gearbox overheat alarm come on whist towing a heavy caravan up a steep incline in the South of France in the summer months.
I found the fan on my gearbox cooler was caked up in mud preventing it from working. When I freed off the fan it cut in and the alarm reset.

Dave
:)
 

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Not that I know diddly squat about the diesels nor the particular issue, but highway driving and casual local road driving is not much of a stress on a gearbox when it comes to temps. Towing, slow slogging on hot days in stop and go traffic, and crawling around offroad/up and down hills, with a lot of idle time and not much air movement would be times to really examine the gearbox temps to see if there would be an issue.
 

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Yes I have a fan on my 2000 my DSE. I understand the fan was added to later models.
Landrover obviously knew there was an issue with the auto box overheating under heavy load in hot climatic conditions.
Also as a side issue my gearbox cooler is tucked under the LHS front wing. It is easy to whack it as I can testify.
Am I right in saying even later model DSE's - 2001 onwards - had the gearbox cooler at the front ?
I thought about doing the mod but there doesn't seem room.
It would solve the problem with the fog lights.

Dave
:)
 

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Microcat shows PGF101790 as fan/cowl motor assembly fitted from VIN XA410482

Just goes to show that every day is a learning day with a P38, as I never knew the later ones were cooled as standard, I just bought a motorcycle radiator fan as they are well sealed and small.

This is from the electrical section of RAVE. The 1999 on electrical section describes the electric fan, the 1997 electrical section does not. Interestingly the 2000 edition of RAVE that I have does not even mention this fan in the main gearbox section!!

Gearbox Oil Cooler – Diesel
The gearbox cooling process relies mainly on ram air
entering through an aperture in the LH side of the
bumper moulding and is dispersed over the oil
cooler. The cooled oil is fed back to the automatic
gearbox via the return pipe, which is located parallel
to the feed pipe on the LH side on the automatic
gearbox.

A small electric fan is fitted to the front of the oil
cooler to cool the gearbox oil during long periods of
elevated gearbox oil temperatures i.e. during
extended idle in drive or low speed towing. A
gearbox oil temperature switch is fitted adjacent to
the warning light switch on the oil cooler. This switch
monitors the gearbox oil temperature. When the
gearbox oil temperature reaches 95  C ± 3  C the
switch provides the ground for the oil cooler relay
located in the engine compartment fusebox.
The relay receives a power supply on pin 86 from
shorting link 8 (J792) in the engine compartment
fusebox. The ground for the relay pin 85 is provided
through the gearbox oil temperature switch. The
relay therefore will not energise unless the gearbox
oil temperature switch reaches its defined limit of
95C ± 3C.

A separate power supply is connected to the relay
pin 30 from fuse F28 (30A). When the gearbox oil
temperature switch energises the relay, power is
routed via relay pin 87 to the electric fan located on
the front of the oil cooler.

As gearbox oil temperature decreases the oil
temperature switch deactivates the relay by breaking
the relay coil ground circuit. As the ground circuit for
the relay is interrupted, the power supply is
disconnected.

The ground for both the gearbox oil temperature
switch and the electric fan is via a ground point
(E0557).
 

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Here is a pic of the gearbox oil cooler on my 2000 DSE showing the fan.



Dave
:)
 

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I may have to look at puting a fan on there even if manual - I do once in a while get a high gearbox when off roading
 
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