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Discussion Starter · #1 ·
Following the demise of my trusty X type, thanks to a M5 driver pulling out, plans have been moved forward to replace it with an X350. As things stand today, It will be used for round trips of about 60 miles, with 50+ of those miles being motorway - around 10K miles/year. I am not looking for a low mileage "show" car as the use it would have would not be dignified for such an item.
Questions is petrol or diesel?
 

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Jaguar XJ X351 Portfolio 3.0 V6 D Caviar
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Big battle going on in my head right now there is o_O:ROFLMAO::ROFLMAO::ROFLMAO:

Pros & Cons:
Diesel - noisy, dirty, fuel costs more at pump and great mpg
Petrol - quiet, clean, fuel costs less at pump and not so great mpg

Then I look at my cars and these old arguments don't hold up, so I'm afraid that I'm not much help sheddist with reasoning a sensible answer. for you, but perhaps if I tell you out of all the cars and vans I have owned, how many of each there have been, this might be more helpful ...

Diesel - 99%
Petrol - 1%

Best of luck with you new feline ;)
 
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Discussion Starter · #4 ·
Yes, the advantage of diesel is better MPG, but as the car will likely to have 90K+ miles, it would be foolish not to factor in turbo rebuilds, inlet manifolds, EGR and even DPF. All money better spent on a full brake and suspension rebuild! Petrol cars seem a little cheaper, so based on my use, the fuel on cost is about £30/month at current prices. What is the real world MPG?
 

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Jaguar XJ X351 Portfolio 3.0 V6 D Caviar
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Yes, the advantage of diesel is better MPG, but as the car will likely to have 90K+ miles, it would be foolish not to factor in turbo rebuilds, inlet manifolds, EGR and even DPF. All money better spent on a full brake and suspension rebuild! Petrol cars seem a little cheaper, so based on my use, the fuel on cost is about £30/month at current prices. What is the real world MPG?
Wow! You got me there my friend! :oops:

These things don't enter my psyche so better wait for the more big cat educated and experienced folks to pop along and provide some better advice and help me thinks ;)
 

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Yes, the advantage of diesel is better MPG, but as the car will likely to have 90K+ miles, it would be foolish not to factor in turbo rebuilds, inlet manifolds, EGR and even DPF. All money better spent on a full brake and suspension rebuild! Petrol cars seem a little cheaper, so based on my use, the fuel on cost is about £30/month at current prices. What is the real world MPG?
I bought petrol x 350 v8 8 months ago in reasonably good condition with similar daily usage...sorted it...and am very happy with it.
Good luck
 
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It depends on your usage. 25mpg for a V8 is a good average 20mpg if short journeys or heavy foot.
30mpg on a run.
The V6 will do 1 or 2mpg more than a V8 and the supercharged V8 about 1mpg less. The V8 is a bit faster, more linear and smoother when revved.
 

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So I was going to buy a TDV8 Rangie L322. Figured 25mpg average on my runs, and trouble and rust... Always missed my X308 but didn't miss the rust. Decided on an X350. Ok, diesel will do about 40mpg+ for me I reckon. But the engines are not exactly known for reliability and tbh I've been getting sick and tired fixing modern fragile diesels. I wanted a V8 petrol but they were a lot more expensive to buy and fuel would definitely be more. Then I remembered I'd regularily get 34mpg on a run in my XJ8 3.2 so surely the newer ones would be better ? Reckoned I'd get mid/high 30s on a run and about 30 average. Then things made more sense as much more reliable so I'd save on garage bills AND have a nicer engine. In the end I kept reading about the Super V8 and it's rare offering of the sporty engine but luxury ride and trim. I never liked the blacked out trim on the XJR- Jags should be black with chrome trim and cream leather as far as I'm concerned. I missed a Sovereign diesel but accidently forgot to enter diesel in my search and found a black Super V8 with cream leather. And very, very cheap... Drove it back to South Wales from Yorkshire a few weeks later and got 38mpg. Wow... Nowadays doing my 100 mile each way -half motorway, 35% country A road and 15% shitty Oxford- I get 35mpg. Do much around town and I average 26mpg over a tankfull. And no diesel nastiness. I drive nice and easy but it's good to know the supercharger is there should some oik need putting in their place within society and I know I'd always regret it if I'd bought anything less. It's not just the mpg, it's the cost of the fuel and maintenance too. Look at the bigger picture. Then get the V8.
 

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Discussion Starter · #9 ·
Thanks Spacemonkey, it is indeed food for thought. Agreed that the diesels can be a PITA once injectors/sensors drift out of calibration, together with the other potential issues. We also have a D4, which is a body off job to change a turbo! The big advantage of the X350 is its light weight, especially with a petrol engine. The diesel is lugging around an extra 120 Kg which negates that somewhat.
 

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Discussion Starter · #11 ·
Could be... The V8 have a lower diff ratio so cruising rpm are less than with v6. I had an XK8 with the 4.0 V8. I was not happy with that and remain convinced it was detuned to protect the 5 speed box, which when mated with 2.7 diesel in the discovery 3, resulted in shredded transmissions. No such worries with the 6HP. Daft thing is that I can drive a V8 into the Birmingham clean air zone, but not a 1.5 pre Euro 6 diesel. Work that one out Greta!
 

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Could be... The V8 have a lower diff ratio so cruising rpm are less than with v6. I had an XK8 with the 4.0 V8. I was not happy with that and remain convinced it was detuned to protect the 5 speed box, which when mated with 2.7 diesel in the discovery 3, resulted in shredded transmissions. No such worries with the 6HP. Daft thing is that I can drive a V8 into the Birmingham clean air zone, but not a 1.5 pre Euro 6 diesel. Work that one out Greta!
It's the same for the 5L so why is it in the highest road tax band if the engine is so clean 🤔
 

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Road tax is co2 based. Which is daft but designed to slow global warming. Clean air zones are for the air quality at street level.
What isn’t fair is that a four year old £1m Bugatti pays less road tax than a 15 year old Jag. When the Jag is cleaner on all counts.
 

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In regards tax my 2004 4.2 v8 is £360, same engined car registered after march 2006 will be £630

So if tax is something you are taking into account then maybe look for a pre march 2006 car.
 

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Discussion Starter · #16 ·
Found a 4.2 LWB Sov. Very tidy inside and out with 92K and been sat at the dealers place since Dec 2021 when they took it as a PX. Good MOT history - with previous owner doing less then 5K miles in 5 years.
Was a bit sold when it started, bonnet up - needed to be jump started due to low battery, so a very cold start. Started instantly with not a rattle then settled into a silent idle. Much better than my 4.0 XK on cold start. Bit surprised that it has a cassette slot!
 

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I think until 2004 came with cassette.
2005 had c.d..
How much they asking?
 

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Discussion Starter · #19 ·
Well, just picked it up and serenely wafted home. Jobs planned:
  • Clean out tree debris from plenum. Car spent 11 months parked under some trees. At least the pigeon population did not find the trees attractive.
  • Sort out cabin filter retaining clips
  • Fit late X type bluetooth module and aerial - parts in hand for this.
  • Make jacking blocks so trolley jacks can have same interface as the screw jack- more axle stand options
  • Wheels off and have a really good look underneath. Grease registers and studs. I am expecting a bush or two to need replacing.
  • Tease all the various underbody bolts and screws, replace with stainless where they are not into aluminium and replace self tappers/screws into steel clips with m6 stainless screws into tapped plastic blocks. Hopefully all the cover/liner/bumper cover fastners will become a 10mm head nut/screw. Big timesaver for servicing and dealing with issues to come no doubt.
  • Check behind headlamp earths
  • Polish headlamp lenses
  • Treat leather to some leather balm
 

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Well, just picked it up and serenely wafted home. Jobs planned:
  • Clean out tree debris from plenum. Car spent 11 months parked under some trees. At least the pigeon population did not find the trees attractive.
  • Sort out cabin filter retaining clips
  • Fit late X type bluetooth module and aerial - parts in hand for this.
  • Make jacking blocks so trolley jacks can have same interface as the screw jack- more axle stand options
  • Wheels off and have a really good look underneath. Grease registers and studs. I am expecting a bush or two to need replacing.
  • Tease all the various underbody bolts and screws, replace with stainless where they are not into aluminium and replace self tappers/screws into steel clips with m6 stainless screws into tapped plastic blocks. Hopefully all the cover/liner/bumper cover fastners will become a 10mm head nut/screw. Big timesaver for servicing and dealing with issues to come no doubt.
  • Check behind headlamp earths
  • Polish headlamp lenses
  • Treat leather to some leather balm
Superb, great news Sheddist, and love the plans already in place

Next thing is to get some pics added, the sooner the better too, especially if she needs a good clean etc as that way the transformation will be even better

Cheers
Jim
 
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