What a post. If properly maintained they are fairly reliable cars. Parts are pricey. Low volume equals higher cost and profit margins on parts. Parts cost are comparable to most higher end Euro imports.

As you mentioned Jags along with most other cars, once past 100K miles are rarely for sale because at that point most people drive them to their grave.

Well maintained ZF trannies in these cars can last up to 150K miles although 100K is more common. The drum is the weakpoint in this gearbox as they fatigue and crack. A good rebuild will cost about $2,400 and figure about 4.5 hours labor to remove and install. A good rebuilt with proper fluid changes (once ever 30K or miles or so) should give you another 120-150K miles of trouble free service.

My advice in just have a compression and leakdown test on the motor. A nikasil motor actually has better wear characteristics than steel liners. The nikasil coating is extremely hard and wears very well as long as it isn't overheated and low sulpher fuel was used. If it's a CA car then it shouldn't be an issue as low sulpher content fuel has been required in CA since the late 90's. Actually all things being equal, I'd rather have a nikasil motor over a sleeved motor if all the numbers were the same. Nikasil gets a bad rap, but has been used in high end motorcycles for years. Motorcycle owners tend to more fanatical about maintenance than your average car owner, especially your typical Jag owner.

I had a heavily modified '99 XJR that I sold to a friend and he is still driving the car with 210K miles. We ran a compression test on the motor for kicks last month the weakest cylinder still had a reading of 148. That's pretty darn strong.

The cars weakpoints are wheel bearings, ball joints, valve cover gaskets, and cooling system components, (thermostat, hoses, and distribution pipes).

All in all, if you can buy a good used car for let's say $10K and put another $5K into it (worse case scenario which includes a new trans and tensioners) and have $15k into it, what would you rather drive, a Jag or a 2 yr old Hyundai?

 

Phil:
I can give you a good answer to some of your questions and my anything but humble opinion on some others.

Do XJ300s last more than 80 k? YES! I own and drive an XJ6 with 235,000 miles on the original engine and transmission. I own and drive a 98 XJR with 230,000 miles on the original power train. My wife drives a '02 XJ8, bought new with 145,000 miles, with very little service history. All of these cars are driven hard, especially the ones I thrash about.

Are they trouble free? NO!. There are known issues with the X308s including water pumps, timing chain tensioners, wheel bearings, early transmission failure, Nikasil engine failures and a host of lesser maladies. Get past the Nikasil, or buy an '02 or newer (in which these problems were already fixed) and you are taking a smaller risk/

Will it be a money pit? If you buy a 12 year old car, and take it to the dealer for everything from oil change to new batteries, the answer is ABSOLUTELY YES. If you find a good independent, the answer is maybe. If you will work on it yourself, at least through water pumps, alternators, brakes, wheel bearings,and so on, they are not particularly more trouble nor expense than any other car. And for the most part, I find them fun to work on. Notice, I have the three mentioned plus a XJ-12 convertible in order to be fairly sure of having one in good working order for my wife and another for me to drive at a particular time!

Some of what I told you is probably true.

 

Hold on there Phil. I should have been clearer. As to Nikasil, there is some risk and a lot of concern about it, but I agree with Wazari. If the Nikasil; doen't succumb to premature failure, you get supercharged engine with 235,00o miles, burning no oil and with good compression amd lots of GO! All things being equal, I probably wouldn't seek one out because of the small risk of very bad consequences if the Nikasil corrodes.
Good luck and go buy a smile for your face.

 

Bottom line I guess is just have a compression test and leakdown test done on any motor. Nikasil doesn't really corrode, it breakdowns under the wrong conditions. Nikasil itself is a very hard, wear resistant coating, superior in wear characteristics compared to steel. 98 and 99's would have nikasil motors if its the original engine.

Tranny fluid changes should be down on a regular basis. A transmission flush is okay if done early in a transmission's life and on a regular basis with proper fluid. I don't know of anyone doing a tranny flush with the proper Shell or Esso fluid for these ZF trannies.

 

That's been a very good thread yet informative I should say and thanks for everyone for their valuable inputs
On the other hand the more I read the thread the more confusion runs thru my mind related to the nikasil .
What makes me puzzle is that since nikasil is very hard and wear resistant coating why on earth some engines blown away very shortly and been junk for a Jaguar engine ?
Then sulphur itself supercedes over nikasil either nikasil should not be used in any engine or nikasil engines used in those Jaguars which needs to be replaced must be crap or so

 

Nikasil (trade name) is a coating (plating) process. It was mainly used by Porsche and still used widely today. Low quality gasoline with a high sulphur contect would etch and eat away the coating therefore causing the engine to lose it's sealing and compression. The cause for nikasil failure is bad fuel or prolonged overheating but typically the former. The is why for example BMW speciifically called for a certain brand of gasoline in their owner's manual but how do you police that?

So as a long term cost savings measure some manufacturers switched to steel sleeves whereas some like Porsche continue to use Nikasil to this day. Nikasil is a low friction, low wear plating that works very well in internal combustion engines as long as it's not abused.

 

Thanks wazari for your post , bad fuel adversely affects nikasil engines more than steel lined ones I think . Anyway you should always use a good fuel that always counts for any engine

 

Just to be clear, I have never seen a report that there was a correlation between price or brand of fuel versus the sulphur content. It was by country or geographic region in the U.S., dependent on the refinery and source of crude oil, as I understand it. Apparently, the sulpher content is OK in all parts of the U.S.

 

No official correlation between between brand and sulphur content back then althrough one brand did use additives to try and neutralize the sulphur effect in their gasoline. It was both regulated by state and feds. Now it's no more than 30 PPM nationwide. CA was the first to mandate that standard in the mid-late '90's.

There is a correlation between brand and quality of gas. But that's another thread.

 

@ Phil

I think the most important thing to consider is that either of your choices is going to be an used car > 6 years old. In those 6 years there is huge potential for the car to have been abused, especially an XJR.

I think it's essential to be able to talk to the previous owner (hopefully there is only 1) and get a gut feel about how they've taken care of the car.

I looked at a lot of cars before I bought my XJR and I was amazed to see 2004/2005 XJRs that were basically destroyed inside simply because people hadn't looked after them (coffee spills, scratches everywhere, rips in leather, headliners, etc). On the other end of the scale I looked at a 96 6cyl XJR which was absolutely immaculate... I mean concourse... The guy had a 4 post lift in his garage (nice toy) and every week he took all of the wheels off and washed the insides of the alloys... you get the picture.

I finally settled on a 2000 XJR which was 1 owner from new, big stack of history/bills. 200USD valet every 2 months, etc, etc. When I asked the owner why he'd bought an XJR instead of an XJ8 his wife piped in and said she prefered the wheels on the XJR, so thats why he bought it for her ! She had no idea of the performance of the car and I succeeded in terrifying them both during the test drive :-)

Insurance costs : Geico told me the difference between XJ8 and XJR for me was about 100USD per 6 months

Performance and it getting you into trouble : I am constantly being overtaken on the freeways here while sitting at 80mph by pick up trucks and Pruises, etc, etc so the old saying about a car only being as fast as you drive it applies here. There is also no law against breathtaking acceleration down a freeway on-ramp so feel free to use this to get your speed fix.

Running costs : Tires, brakes and fuel --> bad. Mechanical bills...... I haven't had any in the 1.5 years I've had the car. (The auto dimming rear view mirror packed in which I fixed myself) This covers 82k to 96k miles

Feel good factor : Amazing. I used to have high end Japanese cars when I was in the UK and I know what you mean about utter reliability and for sure some of them are great to drive (ie 300ZX Twin Turbo) but at the end of the day a Jaguar is a Jaguar and it is different. They are also quite rare so they tend to stand out a bit more.

While I think it's great you are doing your homework and checking up on what could go wrong, I often think forum boards paint a much worse picture of the car than is reality (not just Jaguars, this is true of any car bulliten board). 99% of the posts here are because something has went wrong on someones car, and I do admit there are some horror stories out there and people have been seriously burned but there are never any posts to say "I had a great trouble free motoring experience in my Jaguar today" so don't be put off by the apparently huge list of things that "could" go wrong. You have got great advice from others about the Nikasil issue. Once you get to the same amount of info on the timing chain tensioners you should be able to make an informed decision :-)

Good luck and let us know what you finally get

 

You could also do what I did and buy an older V12 XJS as well. This makes an X308 XJ appear to be the most reliable car in the world by comparison :-)

 

what's this talk about crappy trannys? I own a 98 XJR and am reasonably familiar with all of their problems and quirks - but trannys only lasting 80K is a new one. In my humble opinion, the mercedes tranny is one of the best things about this car. I've seen a thousand threads in this forum on nikasil, thermostats, wheel bearings, and the dreaded tensioners ... but very few on blown transmissions. If one of us is misinformed on the reliability of the M/B 5 speed, I hope it's you.

 

As far as the question about an xj8 or xjr, my experience has been that the xjr's that I have looked at, some of which I have bought, were better cared for than the xj8s. I think people who know the difference take better care of their cars. Also, the xjr's are much more luxurious inside. While 370 hp seems like alot, you do get used to it. I don't know how I would react with an underpowered car. While I rarely tap the potential of the engine, it is true that I love empty freeway onramps.

 

In all fairness to the XJ8, I don't know if I would go as far to say that the XJR's interior is "much more luxurious". As far as I know, the main difference is the sport seats (which are a matter of taste, as I like the traditional look of the XJ8's better than either the sport or the Vanden Plas seats), and the wood/leather steering wheel. All other features (including premium sound) like navigation, heated rear seats, etc are optional across the board or standard equipment. While I admit the performance of the XJR is amazing, I wouldn't call the normally aspirated XJ8 at 290 hp underpowered, especially from a 4.0 engine.

 

On the other hand, some of us would call the stock XJR underpowered!