Hi Discodance,
Having owned various Land Rovers over the past 35 years I would say that I’m fairly well acquainted with their many idiosyncrasies and I did indeed tread the same path you are now contemplating.
After many years of reliable motoring in our old Tdi300 Disco 1 we decided we needed a bit more oomph to tow the (bigger) boat, to this end we started researching the Disco 3 TDV6 and on paper it seemed to tick all the right boxes, 445 Nm of torque, plenty of cargo space, relatively decent fuel consumption, luxurious air suspension, leather interior, fantastic sound system, ridiculously bright headlights (a far cry from the old Lucas stuff!) and what a handsome looking beast!
So after shelling out a huge wad of cash on a lovely 2007 HSE we took delivery of what was about to become the biggest mechanical saga of our lives so far…..
Having owned one V8 Disco2 (the horror) and two Td5 Disco 2’s, a series 2A, three Range Rovers and the aforementioned Disco 1 I was familiar with the mechanicals and the various foibles of these vehicles and I acknowledge that they do require a high degree of nurturing for lack of a better word, but nothing could have prepared me for what came next.
The first thing that needed doing was the timing belts as there was no record of them ever being done but to make matters more complicated (read: expensive) was that the general consensus at the time was that the earlier version of the oil pump housing (which the timing belt tensioner attaches to) was either of poor quality metal from factory or of an inadequate design and that slight over tensioning of the retaining bolts could crack the housing causing the idler/tensioner to become loose resulting in catastrophic engine failure (interference motor)
So after lightening my pocket of a touch shy of 3k we were back in business, next on the agenda was the transmission…
The 6 speed ZF Box comes with a throw away plastic pan that needs to be replaced each time the transmission is serviced however you can retro-fit the steel Range Rover pan which is of course re-useable and this is the option we went with, say goodbye to another almost 1.2k…ouch!
Next on the agenda: the lower control arms, not economical to replace just the bushes they said… have to replace the entire arm they said, at this stage we are just talking about the front lowers but in time, they will all need replacing, 2.1k just for the two front lowers…
Then came the broken EGR’s (there’s two of them) and the subsequent coolant reservoir bottle replacement, then the brakes and tyres, these things are heavy and chew up both brake pads/rotors and tyres like there’s no tomorrow!
Then the straw (more like a huge tree trunk) that broke the camel’s back… oil migration into the brake booster….
We had this fixed and traded it ASAP for a Hyundai and have never looked back…..
Needless to say there were many more less impactful expenses along the way but suffice to say that in less than 3 years of ownership we calculated that the servicing and maintenance bill was somewhere around the 20k mark and on our income this was just not sustainable.
Having said all of this I still to this day maintain that the Disco 3 is the most comfortable, best riding car I have ever driven, and I have spoken to one guy that has had no problems with his 2005 Disco 3 at all! (just the one guy)
The power was rather uninspiring, although I feel like this is largely due to the weight and power to weight ratio, the brakes were never strong, it wallows around corners like a prawn trawler and the interior felt overly plasticy with various bits having broken off, also the material lining the A pillars was beginning to come away and the whole interior just felt cheap and nasty.
I have since bought another Disco 2 TD5 and am much happier; in my opinion moving to a D3 is not an upgrade, if you can afford the monstrous maintenance I would skip it and go straight to a Disco 4, or better still, buy a Land Cruiser!!

