Citroen XM timeline doubts

[diuco]

Hello there.
I'm a bit confused on when all the restylings and features appeared. From what i've read in 1993 hydractiva II was added to the XM (though probably the one with 7 instead of 8 spheres), and later in 1994 a 2.5 TD engine was added as well as the general restyling.
My question is did the 2.5 diesel appear before the restyling? Also, did those pre-1994 "phase 1.5" models have rear wheel steering? What features were added only after 1994, and do those later cars have any suspension advantage over doing this to an older one https://frenchcarforum.co.uk/wiki/Modif ... Regulation?
Thanks for sharing your knowledge.

[CitroJim]

As far as I know, the 2.5 TD came along with the Series 2 'facelift'. I've never seen a series 1 or 1.5 with the 2.5 TD in the UK...

I'm not aware of any changes to the rear suspension throughout production that might change the rear-steer feel...

The difference between Hydractive I and Hydractive II is very, very significant. Night and day in my experience...

[xantia_v6]

I agree with what Jim has said. The 2.5 was only available in the series 2.

The rear wheel steering was achieved with compliant rear subframe mounts which were fitted throughout production.

Note that antisink was not fitted to all variants at the same date, for example the PRV engined V6 never got antisink, although in production till the end of 1996.

[diuco]

Thanks for clearing my doubts so far.
So for the v6 it's diravi or anti-sink...
As for the rear passive steering wikipedia says it was added with the facelift so that's why I asked.
The 1993-94 models already had hydractiva II (though not sure about the diesels before the 2.5 arrived), so were there any other major additions after that date? Does the antisink variant ride better?

[Michel]

The difference between Hydractive I and Hydractive II is very, very significant. Night and day in my experience...

Having owned 3 XMs, with and without Hydractive II, I wholeheartedly agree with Jim. Everything about the car changes with H2, and all for the better. Ride, handling, roll control, steering feel are all vastly improved. The brakes were also more normal.

[CitroJim]

Does the antisink variant ride better?

Anti-sink makes absolutely no difference to ride quality at all but as Michel says, Hydractive II certainly does...

Anti-sink is simply a series of valves to isolate the suspension system in such a way that the car does not sink when the engine is off and it's been resting for a few hours...

[diuco]

Does the antisink variant ride better?

Anti-sink makes absolutely no difference to ride quality at all but as Michel says, Hydractive II certainly does...

Anti-sink is simply a series of valves to isolate the suspension system in such a way that the car does not sink when the engine is off and it's been resting for a few hours...

Interesting, though according to wikipedia changing the valves for the ones in the Xantia wouls improve the ride even more:
"Although the Hydractive suspension coped superbly with undulations and driving at speed, it could be unexpectedly harsh if a sudden change in road height was encountered at moderate speed - e.g. lateral ridges or speed bumps. Citroën finally addressed this, and for Xantia (which shared the Hydractive system with XM) came up with a modified design of the suspension (centre sphere) regulator valves, which made them immune to hydraulic impulses produced by the road surface, and which could push the older-type valves into Firm mode, just when this wasn't needed. The modified valves were fitted to production Xantias from 8 March 1999 (and were available as replacements), but were not fitted to XM, which was nearing end of production. Interest in these new-type valves has led to a good few XM owners successfully fitting them, and benefiting from a noticeable improvement in smoothness and consistency of ride."

Perhaps these were the H3 improvements...

[CitroJim]

Interest in these new-type valves has led to a good few XM owners successfully fitting them, and benefiting from a noticeable improvement in smoothness and consistency of ride."

Yes, I know of a few early Xantia owners who've fitted the late sphere blocks (referred to as 'valves' above) with reportedly good results. Definitely worth trying them on an XM if you can find any. They're a bit like hen's teeth...

They can be identified by having bleed nipples similar to those found on a brake caliper on them... Don't try to open those nipples... Likely they'll be well seized in place and will shear... There's no need to anyway...

[diuco]

That's nice to know... Is there any other signifficant improvement that didn't make it to the XM before 1994 but could be adapted that you know of?

Does the antisink variant ride better?

Hydractive II certainly does...

Also how comfortable is the H2 compared to the "regular" hydroneumatic? This probably doesn't belong to this thread but I've heard so many people in the internet saying the CX hydroneumatic was softer... just curious about your thoughts on it.

[CitroJim]

I've heard so many people in the internet saying the CX hydroneumatic was softer... just curious about your thoughts on it.

You can't really compare the two. Apples and pears.. The CX, along with the DS and GS, have a very different suspension arrangement at the front especially and this, in conjunction with the long travel of the suspension at both ends and very soft spheres accounts for the legendary comfort of these fine cars but with considerable roll on corners and not particularly 'sporty' handling even though roadholding was always very good. The Early hydraulic Citroens were lovely to travel in - a bit like riding along on a comfy old sofa and their 'magic carpet' ride was well justified.

Hydractive was a very good way to have the best of both. A comfy ride with very good handling... Hydractive II achieved this and was more or less perfected with the Xantia Activa system which combined good comfort with zero bodyroll.

The Hydractive II XM and Xantias were very lovely and comfy but all was put in the shade, in my opinion, by the hydraulic C5 X7 with Hydractive III. The most comfy car I've ever ridden in and it seemed to go round corners well enough too.

I've never ridden in a C6 but I'd guess it was as good or maybe just a bit better...

[xantia_v6]

I have fitted the late Xantia valve blocks to both my Xantia and XM. I would say that they address design defects rather than being a step towards H3+.

See the long version here: viewtopic.php?p=494381#p494381

[myglaren]

I've never ridden in a C6 but I'd guess it was as good or maybe just a bit better...

Trainman's C6 was a wonderful experience. Not quite like other C6s in that an update had not been done to the suspension software and he refused to let them do it. Exceptionally soft and floaty, like a waterbed almost.