XJ6 STRANGE GEARBOX ISSUE???

[smakkar]

Hi everyone. I'd be grateful if someone could shed some light on my car's somewhat strange behaviour recently.

I will be cruising at let's say 40 mph, and the gearbox will be undecided as to which gear to be in. It will fluctuate from a gear giving 1800 revs/min to one at 2000 revs/min, and then back, and so on, fluctuating every second or so. If i speed up, slow down, or change my throttle position, it then stops happenning. This issue isn't just at this one speed, it happens at differing speeds but always between two gears giving <2000 revs/min.

The car has done only 32k miles and is a 53 plate 2003 X350 XJ6 3.0 auto.

I would be grateful for your expert knowledge in this area. Many thanks in advance.

[numptie-boy]

Very common gearbox fault on these cars. You can get a gearbox re-flash done at the main dealers and possibly a software upgrade. This should cure it.

If the fault persists, it can be a torque convertor problem.

[Redeyes]

Had this problem with my 03 and when speaking the Jaguar service manager is said that they could re-flash the box. However he also said it may cure it or only for a short time. His suggestion was to put a new torque converter in, it was on the way out.

This is what I had did, car had 60000 miles on it, same thing going on that you have. It was expensive but it never liked back, also the transmission oil is changed which needs done every 60000 no matter what Jaguar say, this is from the service manager who seems to know what he is talking about.

[numptie-boy]

Quite ridiculous that a torque convertor should need replacement at all, let alone 60,000 miles, worse still, 32,000.

I am so glad that i sold my X350, and you really need to question the reliability of some of the major components on these cars, never mind the corrosion issues.

[Redeyes]

Well said!

[smakkar]

Had this problem with my 03 and when speaking the Jaguar service manager is said that they could re-flash the box. However he also said it may cure it or only for a short time. His suggestion was to put a new torque converter in, it was on the way out.

This is what I had did, car had 60000 miles on it, same thing going on that you have. It was expensive but it never liked back, also the transmission oil is changed which needs done every 60000 no matter what Jaguar say, this is from the service manager who seems to know what he is talking about.

Did you not have the gearbox re-flashed then? How much are we talking for a re-flash or a new torque converter? Cheers

[roviw]

Hi, I had a gearbox reflash, they charged an hours labour for it, that was 20000 miles ago and the transformation was amazing, the jerkiness went as did the clunkyness. Well worth doing in my opinion.

[Redeyes]

The torque converter and the oil came to around £750, Still have the receipt, this was with discount! The Jaguar dealer quoted £500 for fitting!

However this is a straight forward job, so I with a little help fitted it with no problems. Hardest thing was removing the exhausts and the smell of the oil!

Gearbox was never re-flashed and the filter was not changed, this will be fitted at 120000 miles. Gear shifts are perfect, when the car was fluctuating by 200 rpm it was really annoying and reduced the driving pleasure. Well worth the money, but it should not have failed!

[dunks_uk]

I've had my 2003 x350 with 39000 miles and it's doing exactly the same thing at the same rpm...only about 200rpm variance but irritating. Doesn't do it all the time though. I hope the reflash helps. Just need to find out if my local specialist can do it.

[smakkar]

My main dealer have quoted £185 for a gearbox reflash! More than I was expecting. There's a specialist in Sheffield that has quoted £60 but I've been advised that I need to leave it with them last thing at night so they can reflash first thing in the morning on a completely cold engine. Although the gearbox is frustrating, it's a nightmare to organise dropping it off and picking it up 9-5 mon-fri, hence I've not done anything about it. I have learnt though that it seldom occurs over 60 mph, , Wonder if the Police would accept that as a reasonable excuse?