I hope this is the right place to ask, I'm considering a future purchase and have a few questions. I've always loved the looks of the XJ ever since my neighbor brought home an XJ back in the early '90s. I think it may be a good time to get a car that I can drive while it's still relatively new.

My current car is a 2000 Cadillac Eldorado. I do like the car a lot, but it has its faults. For one, it's impractically small if I want to take more than 1 passenger. I have the non-touring model, which has the 3.11 final drive. Fantastic on the highway, 27 (US) mpg nominally, up to 30 mpg with cruise set. But very slow off the line unless I want to put my foot into it (which I don't). Also consumes an obscene amount of motor oil (1 qt/1000 miles).

But anyway, I'm wondering what kind of real-world economy the X350 models get? I've seen the EPA specs, but I would really like some owners actual mpg. At steady (70-75 mph) cruise speeds, do these get over 25 mpg?

What kind of everyday, off the line performance would I see? I realize that's difficult to see without actually test driving. I assume, though, that with a 6 speed gearbox it's got a good takeoff gear and can still cruise at an economical rpm.

Also, I'm still not sure if I should go back another generation and look at an X308. I do like the more classic looks of the 308, but in LWB it's not as nice as the X350. Is there a considerable difference between the two generations?

Sorry for the long post, and thanks in advance for any advice!
-Michael

 

At 70 to 75, my '06 Vanden Plas gets about 29 miles per gallon consistently. Actually, driving at slower speeds like 60 or 65 doesn't seem to help increase fuel efficiency. Must be something with the gearing? Around the (congested) city, it's more like 16-17 mpg, though. I get about 20 mpg combined with about half of the miles in uncongested highway cruise and the other half in stop and go traffic.

The X350 non-supercharged cars are pretty darn fast off the line if you put your foot into it, but you can probably out accelerate typical traffic by revving it up to about 3000 rpms or so.

 

I had a couple of the X308 before the car I have now, you will find that the X350 is more economical due to the aluminium construction and at 90mph the rev counter on mine shows around 2500rpm.
I have the 3.5 V8 and the very best consumption on a journey of 150 miles at a steady 75 to 80 gave me 35mpg, amazing !
Generally with motorway driving I can easily see 28-29mpg.
I think our gallons over in the UK are very slightly more than your US Gallons in quantity but not sure by how much.Shorter journeys can get it to drop to 23-24 but that is still very good for a big car like the Jaguar.
Best of luck with your choice.

 

Thank you both for the replies! Just what I wanted to know. 29 mpg hwy with the 4.2L sounds great. That sounds much better than some of the other cars I was looking at.

So all the X350s are the aluminum body? I wasn't sure if all were, or just the later models (I have the '08 brochure, it sort of made it sound like only the newer ones were).

Are there any odd issues with the 4.2L V8? Like ridiculous oil consumption due to a faulty ring design, or cold start knocks or anything? I remember reading some of the old 4.0L V8s had their block material and tensioner issues--none of that in these new engines?

Roviw, if you don't mind me asking, since you had both the 308 and 350, which do you like better overall? I'm still undecided--I like both generations too much LOL

 

Hi, I personally preferred the sleekness and shape of the 308, I had two of the long wheelbase models, both had about 140000 miles on them when I sold them, very good cars and always got nice comments about them.
The 350 is generally a better car, more economy, better built, a really modern design in 2003 due to the aluminium construction. The car is not so sleek as the earlier ones, you notice how much taller it is when you try to wash the roof !
The 350 also has the brilliant 6 speed box and more toys, I have the television, the sat nav and touch screen and it is in a superb metallic red which really looks stunning as well. Again lots of very favourable comments as well.
There are some issues with wishbone bushes and also the air suspension can cost a bit if it goes wrong, you will find these things on the forum if you search for them.
Also have a look at the UK forum as well, you should find it interesting as well.
http://www.jaguarforum.co.uk/index

My car had 52000 miles on it when I got it 4 years ago, it now has 155000 and really is running very very well, no rattles or squeaks, anyone in the car is amazed at the mileage and condition. I rarely put much oil in, it is brilliant on oil consumption.
I am so pleased with it that I intend to keep it for a few more years, its worth surprisingly little with the high mileage.
On Wednesday I am collecting a New XJ LWB, never ever had a brand new car before , been saving and planning for 2 years now, chose the Claret metallic so they will match !
Will be interesting to compare , it has a lot to beat as the 350 is brilliant in my eyes.
Look forward to hearing what you end up choosing, whichever one , I am sure you will be pleased, this will be my 8th XJ in about 19 years, so a real addict here haha

 

Darn, you're not making my choice any easier I do tend to like the looks of the x308 better, but the x350 is by no means bad. I agree that the x308 is sleeker, it's a very beautiful car. I need to go and actually test drive one of each. I could go with an '03 model, those seem to have solved the engine problems. But the aluminum body, 4.2L and 6 speed are big selling points on the x350.

Thank you for the info and link! Glad to know these cars can rack up the miles. Lots to think about. I'm actually not ready to buy just yet, at least not until this summer or later in the year. So it may be a while before I have a post about my new car. But I'll certainly be back when I do

Good luck with your new XJ! They are impressive cars, to be sure. I'd be in trouble with all that power lol

 

Glad to have had some input and all the best to you, regarding the new XJ, I am going for the 3.0 diesel, over here they expect about 80% of their sales to be the diesel version, with fuel economy over 40 miles to the gallon it does make sense, considering we are paying in the region of $9.4 for every gallon of petrol and a little more for diesel I have to get maximum mpg I can.
the power is still good but not as much as the petrol ones, still hit 60mph in 6 seconds though !

 

Ah, I didn't even know the new ones offered a diesel. The US brochure shows just the 5.0L V8 options. Very powerful, but I couldn't go down to 22 mpg hwy for a daily driver (well, maybe I could if I could afford to buy a brand new Jag lol), but I wouldn't want to take a drop in economy from my existing car.

I saw the turbo diesel in the x350 (I think it was on Top Gear) and that was really nice. It's a shame we don't get diesels offered over here. They are really amazing compared with the diesels of 20 years ago; I'd be happy to drive one. And 60 in 6 seconds is very good! My 4.6L Northstar is 7 sec to 60 (heavy heavy car lol)

 

The diesel is not offered in the States!

 

running slightly off topic here but I think the top gear you saw with the X350 was the one where he drove from Switzerland to Blackpool in the north west UK and managed to get just over 50mpg, everyone over here was raving about that programme and the economy he got, he was initially driving at around 80mph with the air-con on and everything as he actually thought he had no chance of covering the distance on the one tank of fuel !
Autocar, the magazine, also did a proper economy run from John-o-groats in the highest point in Scotland down to Lands-End, the lowest point in the UK, they actually managed the trip and then got back up to a place called Exeter before running out of fuel, this gave them a complete trip of over 1000 miles on the one tank of fuel .
To see the range of models they are offering you could try visiting "jaguar.co.uk" instead of the ".com" site, it should show the cars available, together with economy figures etc,
whenever I have been in the USA I have always been amazed how much fuel you can put in the car for your money,I remember about 4 years ago in Las Vegas, you had to pay before you fuelled, I gave the cashier a $50 note and said thats what I was putting in, I think it filled at a bit under $30 , I went back in and she said she thought I was being optimistic haha.
the X350 here could cost about $150 to fill up, arghhh

 

That was the episode I had in mind! Must have been an '08 or '09 because I recall the car had the front fender vents. Gas isn't $9 yet, but no more $30 fillups here... so I'm certainly not looking to loose any economy in a new car lol.

Sorry for taking the thread off topic. Was just reading the '08 XJ brochure again, it seems adaptive cruise control was only available on XJR and Super V8 models?

 

Although I have seen 29MPG on a few trips, mostly flat interstate.. a more realistic expectation is 24-26 driving at 70-75 with the cruise set in a mildly hilly area..

 

I have the 3 litre V6 (not sold in the US), and get about 26 on the highway, and 19 pottering around town. So...........

I take the bus to work; as a pensioner I get a pass, so its only 65p a day, or about $1. Using the car would cost me over £5 (=$8) including the car park ticket.

Went out on the motorway to IKEA last night and wow this is a wonderful car for cruising at speed; a pleasure every time when the roads are reasonably clear. It was the M6 too, a motorway road (= US Interstate)that UK readers will know is notorious for very heavy traffic especially in Cheshire. I must have got lucky !

 

What about the air suspension, I've been reading up on the spring and compressor repairs, is it worth it? Is it noticeably smoother than the x308?

 

No it's not any smoother. I guess the only advantage is you don't get that "hooptie" look when you have a lot of cargo and/or rear passengers because the air suspension is self leveling.

I think the main benefit of the X350 over older XJs is it's a bit quicker, it is much more agile, and perhaps most importantly for a flagship luxury sedan, it's much bigger inside.

 

Oh, the old models don't have rear leveling? That's a bit of a surprise (but not a big issue for me).

Hmm, I didn't realize the 350s were that much bigger inside. That is imporant to me, one of the main reasons I'm looking at another car. I noticed the x350 has a longer wheelbase, but overall the x308/350 are nearly the same length.

I don't know... I can't make up my mind. I like the x350s, but there's something about the body that doesn't speak to me the way the x308 does.

 

Maybe they are, I don't know, but if it doesn't have an air suspension, I don't see how it could be self leveling (did some X308s come with air suspensions?).

 

Oh I don't know... I was thinking like what's in Cadillac (plain shocks with auxiliary air springs in the rear to compensate for loads) or Mercedes (hydraulic rear shocks). I would have figured Jaguar used some kind of load leveling, but maybe not.

 

The early higher-spec XJ40 saloons and the Daimler equivalents had self-levelling rear suspension, but most owners of the used ones ripped these out and went back to conventional spring/damper assemblies as they were so expensive to replace and didn't last long. The X300s and X308s had no self-levelling units.

The X350 models self-level because they have the air suspension with suspension height detectors as part of the system. Heavy loads in the boot are therefore fully compensated, and I can vouch that this is true as I took my daughter to university in the car. She has more luggage than Madonna on Tour, so yes, it does work !!

The 2011 XJ has air for the rear so also compensates for loads, but Jaguar seem to have given up on the front and gone back to steel springs. I hope they can be retrofitted to my car if I have an air spring go on the front, where most failures occur.