[Paul D]

Calling all who have replaced rear ARB bushes with Superflex polyurethane...:

Please can you advise how long Superflex (or similar) rear ARB bushes are typicall expected to last?

I can hardly believe that they can fail an MOT for being too much movement after only 3 years and 20k miles.

Especially as the standard Saab original rubber units (which are Soft - with a capital 'S'!!) passed every MOT for 6 years of which were on Saab before I replaced them with Superflex units.

Is this MOT failure reasonable, or completely at odds with member experience?

NB: Garage doing the MOT is a franchised Vauxhall service garage.

Thanks in advance.

 

[mark e]

90k odd miles and 7 or so years for mine... although to be fair I can't remember which brand they were. Doesn't sound right to me.

 

[Saviour]

Calling all who have replaced rear ARB bushes with Superflex polyurethane...:

Please can you advise how long Superflex (or similar) rear ARB bushes are typicall expected to last?

I can hardly believe that they can fail an MOT for being too much movement after only 3 years and 20k miles.

Especially as the standard Saab original rubber units (which are Soft - with a capital 'S'!!) passed every MOT for 6 years of which were on Saab before I replaced them with Superflex units.

Is this MOT failure reasonable, or completely at odds with member experience?

NB: Garage doing the MOT is a franchised Vauxhall service garage.

Thanks in advance.[/b]

Are you sure you put the right ones on in the first place, 19mm on an 18 mm RB ? I don't mean that to sound bad, by the way!
Mine have been fine for 3 years and 20K

 

[mark e]

I'm pretty sure Paul has a CS, so no. It was the CD and early CC variants that had the 18mm.

 

[AlanG]

I thought the CS had 19mm and bought PU bushes for mine. I found they fitted very easily, and it passed MOT's for several years, but I never found the improvement others raved about. Then I decided to measure properly and found that they were 18mm so replaced them, to good effect. As my car is a '94 CSE I guess it is a case of the common Saab malady of fitting what was available on the parts line.

 

[mark e]

Very interesting, Alan. Could it perhaps be that you had some corrosion on the bar? There is only one part no for all CS models on EPC.

 

[AlanG]

More a disappointment than interesting to me Bubbles. It was not corrosion, still had some paint on it. Maybe a Friday afternoon car when the couldn't tell the difference between a CD and CS (although I thought that was more Frod than Saab).

 

[Paul D]

Good points all - thanks for the feedback.

As Bubbles notes, my car is a CS (CSE Anniversary, 1998), which has the 19mm ARB as standard (same as Aero).

The Vauxhall garage put my car back on the ramp this morning and showed me the play. Left rear Superflex ARB bush is fine, no play. Right hand had approx 0.5mm visible (probably 1mm top and bottom). I fitted them myself (3yrs ago) so know it was done properly.

In conclusion:
The gap/play, in my view was due to paint flak plus some corrosion on the ARB. I'm pretty sure ARB bushes had same size holes when I checked before fitting (3yrs ago) so not a design fault. So buying new bushes would not solve the problem.
The Vauxhall MOT engineer removed the clamp, applied insulation tape, and refitted at no extra costs, then issued my MOT this morning!

Probably an MOT garage which sees more older cars would likely have passed it. That said, I'm happy with the final result, but wonder how much tape will be still present at next years MOT - and hopefully checked by another tester!

1) If anyone notes greater ARB wear on bar under right hand bush, I'd be glad of any further feedback?

I did apply all the grease supplied with the Superflex bushes -
2) Can anyone recommend an after market grease which is compatible with the polyurethane for re-lube’ing bushes?

3) I noted the two ARB hangers, which fix to underside of car, are fitted in opposite directions. Right hand unit has 45degree end facing towards rear of car. Left hand hanger has 45 degree end facing front of car. I think this is normal (and definitely as fitted by Saab when car was made - as I know full service history), but MOT tester raised a query. Can anyone verify this is correct?

 

[Doive]

Very strange. My CSE is an MY94 car, and definitely has the 18mm ARB fitted as standard. I bought the red polybushes last year and fitted them, instant difference in corners despite the very soft suspension. The ARB hangers do indeed point different directions, and are quite flexible in torsion as I found when I tried to undo the nuts holding the old bushes in place. All I can say is I hope I don't need mine replaced every year for the MoT - the ones I replaced were clearly the 13 year old originals, and they still passed without problems.

 

[Paul Anderson]

Paul D,

All three 9000s which I have fitted poly bushes to had the 'unusual' hanger orientation so I think we can assume that this is the correct way so it just shows that your MOT'er doesn't see many 9000s. I think it's possibly something to do with the forces put on them by the orientation of the Panhard rod. ( gives side to side location of the axle ), since it is attached to the body at one end and to the axle at the other. This effectively makes the rear suspension 'handed'.

Paul @ Kippen.

 

[aeroadster]

I fitted some powerflex to mine over a year ago now and they are still ok.

On the subject of regular replacement, 3yrs isn't so bad. A former colleague of mine had a 5 series and over two years he had to replace his poly brushes twice. Luckily it was covered under warranty.

I don't necessarily see poly ARB bushes lasting loads longer than rubber and it doesn't necessarily make a massive difference (or at least I couldn't see the difference), but for the price and effort the little differences it does make are worth it.

 

[sgould]

I haven't fitted poly bushes for years. Never on a Saab. I was told that the poly bushes will last a long time if they are a good tight fit. If the surrounding metal has been previously worn away as a result of, say, a failed rubber bush allowing metal to metal contact, the poly bush will not seat properly and fail quickly.

 

[Doive]

A former colleague of mine had a 5 series and over two years he had to replace his poly brushes twice.[/b]

The 5 series, and BMWs in general, are notoriously hard on their suspension bushes. The E24 and E28 models needed their Pitman arm bushes replaced as a matter of course, and rear subframe bushes usually weren't far behind those. More modern E46 3 series and E39 5 series models are ferocious on the OE rubber bushes, it must have something to do with the suspension geometry and the torsional forces on the bushes, as compared to a car like the 9000, on which my bushes are only wearing out after 13 years and 160k miles.

 

[Paul D]

Thanks for all feedback.

Re. Hanger inverse orientation - confirmed correct via this thread. Indeed the Vauxhall MOT'er evidently doesn't know his 9000's!

Re. Rollbar size. Earlier CSE,s (i.e. 1994) may well be 18mm. My Anniversary model (1998) is definately 19mm (same as Aero).

Re. Rollbar wear under r/h bush. My soft Saab orinals never failed an MOT, and no metal to metal contact. They once recived an MOT 'observation' that they were very soft, and I changed them to polyurethane to solve this and improve roadholding.

Re. Roadholding, as Doive and others report, Polyurethane ARB bushes (front and back) made an instant imrpovement in flatter cornering, and less roll.

SGould - thanks too for the 'tight fit' advice. Makes sense - less movement of bar inside bush will cause les wear.

I also noted my hangers would easily twist when undoing/tightening the bush clamp bolts. Best to hold them steady with molegrips or risk damaging the upper bushes, etc.

Thanks again all..:
As I noted on this forum some 4 years ago, the quality of contribution and product knowledge on this forum far surpases most other car forums I have gazed at! Keep up the good work! :thumbsup:

 

[Doive]

I also noted my hangers would easily twist when undoing/tightening the bush clamp bolts. Best to hold them steady with molegrips or risk damaging the upper bushes, etc.[/b]

I did notice this with mine when I was swinging on them for all I was worth with a ratchet. I think I ended up holding the bracket with one hand while I undid the nuts with the other, or something, to prevent it from twisting and damaging the mounting point on the floorpan. I guess the mountings allow for lateral movement, while locating the ARB mounts fairly securely in the vertical plane.