I was there : Selling the Rover SD1’s rear suspension

First, a couple of component assembly shots. Note how delicate the radius rods and the Watt linkage rods look. This stemmed from a deliberate design strategy to avoid any component doing anything more than strictly necessary – so the rods operate primarily in tension and don’t need to be heavy. The car is pushed along/braked by the beefy torque tube and its cross member – the other bits just guide the axle gently!

Second, is a page from CAR magazine December 1976, from Leonard Setright’s four-page section ‘Any Other Business‘. Len had previously made some dismissive remark about the Rover SD1 live axle, and I had given him the full treatment, including sending him a copy of the patent document.

Bless him, he did take it on board, though he took the patent drawing a bit too literally – as usual with patent drawings, the artwork is rather schematic, and doesn’t represent the exact proportions and angles of the various parts – as you will see from looking at the photos of the actual suspension.

Ingenious thinking

The patent was taken out by a Solihull Engineer, Dennis Warner, who I was sent to see by Spen King while gathering the technical story of SD1. When I later did the Design Award submission for SD1, I had further discussions with Dennis, an interesting guy to talk to. An important part of the design was the way it helped to package the fuel tank in a ‘safe’ location well forward of the rear wheel and thus clear of the rear crumple zone.

We didn’t win the Design Award for this one, largely because the Chair of the Awards Panel was Raymond Baxter to whom we had rather foolishly loaned a pre-production SD1 which had several glitches, such as the faulty oil pressure switch that shut the engine down because it thought wrongly that there wasn’t enough oil pressure – inconvenient at times to say the least!

Also on the panel was Marcus Jacobson, then Chief Engineer of the AA, who objected to things like the need to work inside the car to access the fuel pump in the tank. I pointed out that AA Engineers might be very pleased about this on a wet day!

Rover SD1

A decent solution

Generally speaking, when properly set up, the rear suspension seemed to work quite well. There was one drawback that was discovered by John Bolster and Joe Lowry during the press launch.

They’d gone off our carefully chosen route (of course) and arrived at an unexpected downhill T-junction rather too fast, braking to a halt with the nose sticking well out into the busy main road, John Bolster had rammed it into reverse and given it maximum welly, whereupon the car did a bucking bronco impression – just like a torque-tube Austin Seven, he noted.

Back at the Chateau Impney, our launch base, Mike Brookes decided to try it for himself.Parked the car facing downhill on one of the Chateau roads and did an idiot start in reverse. It shook the car so much that it flung the bonnet open!

Why the P6 arrangement wasn’t used

But it was sad to lose the P6 de Dion rear end. It was partly for packaging reasons but probably more because of the on-cost, which was very substantial. A figure of £35 was quoted early on (over whatever was deemed ‘next best’ – an SD1-style live axle I’d guess). Spen King didn’t like random camber changes!

That was in the days when the P6 retailed at around £1300, so a lot in cost-control terms. It wasn’t very easy to assemble either – in fact, Rover turned the P6 shells upside down to insert all the suspension etc. Something many owners or service mechanics would have liked to do to change rear brake pads!

When we did the Press Launch, Spen King’s opening words referred to ‘schoolboy enthusiasms’ for exotic specifications such as de Dion suspension, as he justified the more rational design for low build and service costs etc.

A lack of drama?

It was ‘schoolboy enthusiasms’ that led Spen, Peter Wilks and George Mackie to concoct their own de Dion rear suspension on the P3-based Rover single-seater race car, and that led to de Dion on the T3 Turbine Coupe and the P6. The P8 was going to have a variation on the theme, too!

I ran several 2600 SD1s and never really found any issues, except one night going a wee bit too quickly in a dark country lane, suddenly seeing loads of weird green lights hovering around a few hundred yards ahead – not a UFO, but a flock of sheep who had got out of a field.

I then heard a large bang, followed by several other bangs as I stopped pdq. The first bang was my foot hitting the brake really hard before I’d actually decided to brake, the other bangs were the rear axle tramping! The sheep survived…

If you were at the coalface and have a tale to share, please do get in touch!

Ian Elliott


  1. Magnificent part 1 of your story Ian. As an ex-owner in Australia of a 1982 3500SE series 2, I’d love to hear more about how the car developed. My own shock with the suspension was going over corrugations on a dirt road to pick up some bits from a wrecker for the car. The darn thing was shaking so violently at a mere walking pace I was going to turn around, but needed the bits too much. It survived, but it was a disappointment for what had been my dream car as a kid when I was in the UK.
    Actually, it was disappointing in many ways, but also very sublime in the right conditions and a joy to have as a ‘thing’, if not an actual car.

  2. Seeing it laid out there you can see just how cheap and nasty the whole chassis arrangement on the SD1 was. This was a premium executive car designed to go head to head with Mercedes and BMW for goodness sake. Even the Ford Granada had properly sorted independent rear suspension. Throw in the cheap and nasty interior and always Friday build quality and the poor SD1 didnt stand a chance.

  3. Using a well location solid axle is perfectly acceptable but the problem was, the SD1 represents another example of penny pinching on a car that cost a fortune to develop. It has been outlined here that the SD1 project was a blackhole into which much of BL’s precious development funds were poured into in the 70’s. So it is hardly an example of a well costed car.

    Another example is the Marina, reusing Morris Minor parts is fine but if you’re going to do that, you should check the condition of the tooling you intend to reuse before starting and it is madness to spend a fortune on a new factory to produce a bargain basement model.

    The O-series is another example, they decided to recycle as much of the B-series as they could, to save money and then discovered the tooling for the B-series was on its last last legs. So they limited their design options for no good reason.

    I suppose I am trying to point out the difference between cost control and penny pinching. One is sensible business practice but it has to be applied to the whole project. In BL’s case it too often comes across as an ill thought out desperate measure to save money on projects whose costs were running out control and in general were badly managed.

    • And I believe the same-pinching, affected the Rover 800? When it was re-skinned as the more curvaceous MkII, the original (flat) roof was retained to save a few pence, for them to them realise they had to replace the worn-out original (flat) roof tooling. They could have included a new curvaceous roof to complement the rest of the MkII’s new bodywork.

      “In the autumn of 1991, the 800 was reskinned and re-engineered under the R17 codename, being launched on 12 November 1991. This saw the reintroduction of the traditional Rover grille and more curvaceous bodywork . . .”

  4. Penny pinching really did sabotage the SD1 straight out of the box. That basic looking suspension set up looks more appropriate for a budget model, not a premium executive car. Plus the cheap interior, as well laid out as it was, and every SD1 I’ve ever seen looked so ramshackle, even forgetting their age. You can even tell by the sound of the doors shutting; rather than a satisfying thud, it sounds hollow and ‘tinny’.

    I was wondering, as complicated as the de Dion suspension from the p6 was, would it have been cheaper in production terms to have simply carried it over to the sd1?

    • Was wondering the same as well concerning the de Dion suspension, especially if they could have embraced similar solutions to its problems like at Alfa Romeo and spread it to other models like the TR7, SD2, etc.

      The SD1’s front and rear suspension would have been better off used in the Marina or its replacement instead of a large premium car.

      • I coudn’t agree more . Having owned a 1.8 Marina as my second ever car many moons ago, and having driven a fair few SD1’s ,I thought thought they were both rubbish. The SD1 was an epic failure in many respects, but the way they drove were paticularly bad. The axle tramping was limiting to say the least and pulling out of junctions could be downright dangerous. I also found the feeling of driveline shunt off putting as well, perceived or otherwise. Under damped, under sprung, they were trying to compete with bmw.
        For a cost effective and better performing system they could have looked at what Hillman did with the Avenger. (No wait). Coil sprung live axle but with two up two down radius arms that would all but illiminate the tramping issue, but look at the angle of the top pair and rootes in effect created an A frame assembly, negating the need (for road use at least) the need for watts linkage / panhard rod set ups. With some outsourced spring damper knowhow perhaps, (the late John Miles springs to mind) my view is that things could have been much rosier for BL.

  5. At the time the SD1 was launched, money was very short in the group. This meant staff headcounts were less than they should have been, designs were simplified/cheapened and there was a hope that enough units could be sold at high enough margins in the first year to at least allow a neutral cash flow – a constraint other VM’s did not have imposed upon them. Fingers were crossed!

    Then an unfortunate blend of poor/cheap interior quality specifications compounded by low volumes of build and highly variable build quality, put paid to any positive cash flow! There were very many frustrated would-be owners in that first year who couldn’t by an SD1, only to later find mindless media hysteria directing them towards buying Teutonic alternatives – which incidentally were themselves not up to much at the time.

    But despite all the anti-Brit anti-BL mouthing off magnified principally by the media, there were many happy customers and I was one of them, having a succession of company V8’s. When I left BL I took my twin-plenum VDP with me and that never had any unexpected problems over 100k, build quality by then was superb although I did have one brainless prat in the car who decided it would be a really good idea to forcibly pull the headlining off.

    For me, the only major criticism of the whole SD1 series was that the rear axle was too far back and had insufficient weight over it. It was too easy to lose the back end and despite my Stirling Moss pretensions I managed to whack the back end on a kerb in the snow, resulting in a pair of new Boges and that Watts linkage buckled. No other damage – to me that translates to good rear suspension design! Then I wasn’t the only owner driving faster SD1’s with significant added boot ballast!

  6. All I will add is a quote by the late Peter Wilks on the subject of the Rover P6.
    Rover Technical Director Peter Wilks later explained the design philosophy behind the P6. ‘We had great arguments in those days with Maurice Wilks about all sorts of things,’ he said. ‘He was against the overhead cam because he said it would be noisy, and another thing he was dead against was the de Dion back-end, which he thought was unjustifiably costly.

    ‘We took the view, though, that for the sake of an extra £35 – which is about what it costs – it was well worth it just to be able to write de Dion in the specification of the car, even if it hadn’t turned out to be any better. We did in fact succeed in creating an image of engineering innovation which had an impact which the car might otherwise not have had.’

  7. I have read, can’t remember if it was here or elsewhere, that the SD1 was compromised early on after John Barber stuck his nose in with his cost cutting, and that a lit of cheaper materials were used because he was aiming for the car to be a Granada competitor sk it wouldn’t affect XJ sales.

    • You may be conflating that with an apocryphal story about P8, which was allegedly deemed too close to an XJ rival to be allowed to live. Various versions of the story have circulated, mostly citing Lyons influence/interference on the board, etc etc. In my understanding, which seems to be supported in the SD1 development article on this site, the P10 (as Rover had developed it originally) was always intended as a ‘Granada competitor’ to access higher volume sales. Conventionality is the order of the day for those markets, where servicing costs are key and the average buyer (usually a corporate) won’t gain the benefit of more advanced running gear. Rover seem to have actively planned this way, and I believe the torque tube suspension was set before the car became the Leyland project, as certain suspension mounting points are shared with the forward-facing de Dion of P8 which would have shared a floorpan (at least in parts).
      Of course the problem facing SD1 was that the cancellation of P8 (rightly or wrongly) forced the new model into the awkward position of having to maintain Rover’s upmarket image as the new flagship for the brand, whilst also appealing to (and being costed for) the fleet market. 15 years later, the E34 5-series did a pretty good job at doing just that, but I don’t feel comparisons to the German auto industry are always useful – especially in the mid 70s. So in many ways, SD1 was always going to be too uncouth to helm the Rover brand, but too costly for the fleet market. (All of the above ignoring build quality issues, of course, which were delivery issues rather than design).

  8. Having driven SD1s and having worked for decades with a man who was a BL dealer and who specialised them (he bought from closed sales and direct from BL management) I can say the only issue with the SD1 suspension was what it was bolted to. Or rather what it should have been bolted to. The quality was shameful and, quite often, sabotaged.

  9. One wonders if the trailing link and coil spring set up of the simple little Vauxhall Viva HB/HC range could have worked as well. It was cheap to produce, had no user servicing complications and (I think but could be wrong) served very well in the Viva GT with it’s much more potent slant four. I’m guilty as charged of thrashing these little cars about and whilst not possessing Lotus handling, the rear end never gave me a moments concern. From memory, the coils performed as good as if not better than the leaf sprung Escort of the same era. And as for quality, I never could align the beautiful ride and interior of my Dad’s P5 with creaky van-like interior of my son’s SD1! That they should both come from the same stable suggests inappropriate parenting at some point.

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