This is just the next in serious problems that we've had with our 2006 XJ Sovereign X350 2.8 Diesel, I love the car but it has been most unreliable.

-It has only 55,000 miles on the clock and only less than 20,000 since the engine was changed for a brand new one (it had a catastrophic failure while being serviced at Jaguar!! ) this was 3 years ago or so.

-Ever since the official engine change by Jaguar, the car has never been as economic as it used to be, it's not bad but not as good as it was.

-This year it had a full service which included the gearbox, also needed the air compressor fixing and replacing as can be seen on my other threads.

-We've noticed since the engine change that when coming to a halt there is a heavy "snick" where the car changes into the first gear this snick coincides with the car jolting forward, Jaguar official service told us this is normal, didn't seem normal to me.

-Just drove up from London to Manchester on the motorway, I got the message "Gearbox Fault" I also noticed slowing down due to traffic to 30mph that I was stuck in a high gear and losing power, so I tried to keep my speeds up.

-5 miles to my destination the traffic unfortunately came to a halt at a red light, I heard a heavy crunch gear change and then I was stuck in 1st gear, I managed to limp the last 5 miles at 30mph with emergency lights on the motorway.

So having said all this does anyone have any idea whats going on?

 

Generally speaking, the mechanical components of this gearbox give no trouble; after all it is used by Mercedes-Benz and others. However, the electronic control software can prove troublesome, and my understanding is this is the responsibility of the car manufacturer, (albeit guided by ZF instructions).

Yet you state you have recently had a gearbox service ! The fault annunciator display will also be backed up by one or more fault codes stored in memory and these need to be read to determine the fault area. For my money, it will be in the software and you need this reloading. As these boxes wear in service the defined pressures defined on each change are checked by the faults watchdog, and this can put the car into 'Limp' mode if it thinks the fault is putting the gearbox at risk of failure.

So, you have to get the fault codes read, and probably a TCM reflash done.

I have to say that the place/dealer you are going to do not seem to be fully up-to-speed on these cars. Where do you live ? There are a couple of excellent Jaguar specialists in the Midlands if you want a second opinion.

 

Thanks Fraser, I've been to all the official Garages in Manchester, Reading and Brussels in Belgium, and they have all been shocking, incompetent and total rip-offs. The only decent service I have ever used is in Dresden, Germany but that is very far.

In Reading after a service they left an injector loose so that diesel was fouling everywhere and it nearly destroyed the injector, I have other shocking stories to relay from Stratstone and other official garages.

I'm based in London and Manchester at the moment, and the car is up here in Lancs (as I have no idea how I will drive down in it now).

I'm not sure as to why since the engine change, the gear always snicked and jumped upon stopping or starting from go, could this be an electronic rather than mechanical issue? The official Jag in Manc told us this was normal.

Other things like the drop in fuel economy since the engine was swapped concern me. The engine was swapped new in Brussels, where the service was atrocious so gives me no confidence.

It was my mother who took the car for the service, she mentioned the gearbox but didn't say exactly what was done.

 

Take the car to XJK Jaguar in Newcastle-under-Lyme, (near Stoke-on-Trent). Mention my name if you want. They are very good at working out how to fix faults like this.

 

Hi Fraser,
I took my other car, the S-Type (rather than XJ Sovereign) which was suffering vibration faster than 30mph, lurch and gearbox clunking but could actually go on the motorway to XJK Jaguar in Newcastle-under-Lyme, and although I cannot fault them I wasn't hugely impressed.

They did rule out a number things I believed could be issues such as prop shaft balance, and told me no surprise there was a gear box fault gear numbers 3 and 4 with no more information, so not telling me anything I didn't know.

They quoted me £3000-4500 for a new gearbox no warranty to my knowledge.

After this a family member took the car to a superb local garage in Rochdale called F & F motors, who took the car to a gearbox specialist towards Liverpool.

Turns out there is nothing wrong with my gears whatsoever the problem lies with the Torque converter, total cost for this job £1500 with a year warranty.

I cannot fault XJK but given they would have cost me an additional £1500 at least I don't think I'll be going to them again, and the car only has 28,000 miles so how could it reasonably have been a gear failure?

 

Ok, but has the £1500 job fixed the problem ?

My experience of XJK is they don't go out of their way to make things expensive, rather the reverse.

 

Yes the problem is totally fixed now and has a 1-2 year guarantee (I haven't seen the car yet as I'm not home so forget exactly how many years), no more vibrations whatsoever, my family members are driving it.

It cost 1500 + Vat for a new Torque Converter with F and F motors Rochdale and not 3500 + Vat for a repair job with a used gearbox at XJK.

 

Just a note the 2006 XJ Sovereign X350 2.8 Diesel at the beginning of the thread was completely fixed and had gear box checked with no issue.

The trouble was a failing battery causing all sorts of electrical gremlins.. Replaced and all cured..

 

Arghhhhh..............the good ole failing battery syndrome again, causes all sorts of strange, weird n wonderful issues.

Thank you so much for coming back to add that this has been fixed and also the source of the problem.

I'll now add RESOLVED to the title thread and this may help others in the future.

 

Any ideas please. I have a very intermittent fault with My diesel x350,not sure if its gearbox related. After the car has been driven for a while and i put my foot down its as if the clutch is slipping the revs go up but the car increases speed very slowly. This has happened on a couple of occasions. I have found however if I stop and immediately restart the car all is back to normal.
Thanks in advance
Steve

 

That sounds like torque converter surge, which is generally a sign of low transmission fluid level. My old Merc had a leaky transmission pan and every few months it would do this. Trouble with the ZF box on the X350 is that it is (so say ...) 'sealed for life', so there's no dip-stick to check with.

 

Thanks for that. Booked in on Thursday for repair.. All I need to sort out now is my bloody Air suspension.

 

£330 lighter. I hate this bloody car

 

That's why it's a Jag, you pay for grace and status..

There are plenty of Mercs, BMWs and Audis for lower class aspirants..