I thought you might be interested in my experience with the transmission on my 2003 2.5 S-type which I bought new and intend to keep for as long as possible.

After 3 yrs (and warranty expiry) the transmission started to play up with the car dropping out of year when cold and re-engaging with a jolt. This behaviour got worse until it was dangerous pulling out at a road junction because the car would drop out of gear and roll to a stop! But only when cold.

Local dealer could not reproduce the problem. The stored fault codes said 'transmission failure' but it drove perfectly for him. I took it to a transmission specialist who removed a plug and smelt the oil, pronouncing it smelled of burnt cork and therefore the tranny would need replacing. Eventually I got the transmission replaced by another main dealer who also said he could not reproduce the fault despite keeping the car and driving it every morning.

Everything was fine for 18 months and the the exact same fault re-appeared. The car would drop out of first gear into neutral and the transmission would bang and lurch alarmingly. Once again he could not reproduce the fault but because the fault codes still said 'transmission failure' he assured me that another new transmission was needed.

Contemplating another £3000 ($4500 US) I got fairly firm with the dealer and complained to Jaguar. Eventually he had to swallow his pride and ask Jaguar for advice. They immediately told him "don't touch the transmission". "Just change the plugs".

That was 2 years ago and the car has driven perfectly ever since. I now know that the first transmission wasn't faulty either, and that by co-incidence the first dealer had changed the plugs at the time, fixing the problem.

So this is a problem perfectly well known to Jaguar that in some ways resembles some of the 'lurch' cases. But I have never read about it on any web forum, which is why I thought I'd contribute this post.

 

I've not read it, either. Thanks for the post.

What miles on the car the first swap and what miles the later occasion?

Also... were there any codes (DTCs) stored in either the PCM or TCM (the computers for the engine & tranny)?

(I'd expect misfires for bad plugs.)

 

Is this the ford 555rn transmission or the Zf 6hp24?

George

 

The 2.5 was only ever manual or ZF. Ahem - that's 6HP26, not 24.

(If it could have it, it would've been 5R55N. Someone's been typing in a hurry or a new phone LOL)

 

Lol in a hurry would be correct! Being in the US, I wonder how a 2.5 S-Type feels. The 2.5 in my X-Type feels anemic as it is, but then it is bogged down by the AWD system. Although that's the reason I keep it around for winter duty.

Take care,

George

 

A bit underpowered I think. The manual box would make up for it (somewhat?) - but a manual jag in this era sounds bizarre.

 

Thanks for the replies. It's certainly a ZF something or other.

The mileage was around 50,000 at first failure and 80,000 at the second. There were no codes associated with the plugs and the dealer didn't bother to find out what was wrong with them. The engine ran normally - no misfires ever. Presumably the whole thing is down to an EMC vulnerability in the design, with the plug HT voltage rising as the electrodes wear. I just wonder how many of the lurching stories have some relation to this.

The 2.5 is adequately powerful for English country roads and I've never noticed it being anaemic, but I'm not a fast driver. It overtakes very well and many people have remarked on the impressive roar that it makes. I couldn't tell the difference between the 2.5 and the 3.0 when I bought it and it was significantly cheaper, presumably because everyone else thought they needed the 3.0! Overall it's been a lovely car (110,000 now) and if only the dealers were a bit sharper ....

 

EMC? Hard to believe. Er... but I'm struggling for another - other than misfires you didn't realise it had. There are frequently some, which normally go unnoticed. Because there are, they won't be flagged unless they reach a threshold.

Anyone with any other ideas? Quite an attractive fix if it works!

 

Well certainly a cheaper fix.

 

Just for curiosity's sake I did some googling. I wasn't able to find C02 emissions or fuel economy figures for the S-Type R but if you have one, those aren't your primary concerns:

Here are the numbers:

2.5 v6

Power: 198bhp
0-62mph: 9.9 seconds /Maximum speed: 140mph
Fuel Consumption: 35.8mpg extra urban, 27.4mpg combined
CO2 emissions: 249g/km

3.0 V6

Power: 240hp
CO2 EMISSIONS: 249-259g/km
PERFORMANCE: 0-60mph 7.3s / Max Speed 146mph
FUEL CONSUMPTIONurban) 18.5mpg / (extra urban) 35.1mpg / (combined) 26.4mpg

4.2 V8

Power: 298hp
CO2 EMISSIONS: 274g/km
PERFORMANCE: 0-60mph 6.2s / Max Speed 155mph (limited)
FUEL CONSUMPTION: (urban) 16.5mpg / (extra urban) 34.2mpg / (combined) 24.5mpg

4.2 S/C (S-Type R)

Power: 390Hp
Performance: 0-60 5.3 secs / Max Speed 155mph (limited)

No wonder they wouldn't bring the 2.5 to the USA. 0-60 in 9.9 seconds wont cut it in a country where the party stops at 65-70mph.

Also amazing was that the S-Type R is almost a full 5 seconds or twice as fast as the 2.5 to 60mph.

Personally unless you had to have the type R (which I'm seriously contemplating). The 4.2 v8 seems to be the best blend of performance and economy. Granted I know there are other factors at play in europe, such as taxation based on displacement etc, drastically higher fuel costs etc, which we are not encumbered with here.

It's amazing that we are in a sense in the middle of a modern horsepower war with the highest real prices for fuel that the USA has ever seen.

George

 

STR official CO2 314g/km

You're right that even with our fuel price it didn't put me off buying the STR. I figured it was likely my very last (and first LOL) chance to have such a car