Changing rear air spring

Hi Everyone

Just wandered how many hours a professional garage that has done it before should allow to change a rear air spring on a P38?

30 minutes. Never do one, always in pairs. Last one I did took around 15 minutes, it was a new one that had failed so all was clean and free.
DIY, it's easy with my guide in the "How To" section.

Not 3 hours then?? What is the reason to do in pairs? just to keep it level or on the basis that if one fails they are all likely to fail, or some other more complicated reason??

moatmeister said:

Not 3 hours then?? What is the reason to do in pairs? just to keep it level or on the basis that if one fails they are all likely to fail, or some other more complicated reason??

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If one has failed, then the others will also be knackered, the design life is 7/8 years 80K miles. A new bag will be more supple than the old bag and will have different characteristics.
Old bags leak and knacker the pump.
Garage are covering themselves, if the bags are old and have the alloy end caps, it can take a bit longer to get them out but 3 hours is taking the **** IMO.

Cheers I will have a go at the other side myself now we are up and running again and there is less time pressure! Is it important to use the same brand on both sides?

ps I have fitted the Mf31 -1000 battery as recommended!

If you know what you're doing and have the right tools 30 minutes is easily long enough. I did 2 rear ones in my time (because I didn't do them both at once..... ); the 1st took ages because it was rusted in and I didn't know whether I was going to break something trying to move it.... but once you work out that a bigger crowbar is the answer it's quite quick!
If nothing was stuck it would take as long as it took to jack and manipulate the pliers to get the pins out and in

The fronts probably take longer as there is less access, but I never had to do them.

I used an old steel coat-hanger to pull the top pins out on mine. They popped out quite easily. If your rears are done then the fronts won't be far behind. I took the wheel liner out on the drivers side for easier access to the front right and have no regrets doing so. Others don't bother.

I've done a full set or airbags on both of our P38's in under 2 hours (including a cup of tea)

Went for the Arnotts on both.

ukadamwest said:

I've done a full set or airbags on both of our P38's in under 2 hours (including a cup of tea)

Went for the Arnotts on both.

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That must have been a long cup of tea

if i had the wife trained properly i wouldnt have had to stop to make one !

ukadamwest said:

if i had the wife trained properly i wouldnt have had to stop to make one !

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If you had she trained properly then she would have done the air bags.

+1
3 hours is abit excessive no doubt they had a lift to do it too, so the hardest part should have been trying to prise the wallet out of your pocket
How much did they charge? Just for a laugh!

He was going to do it himself. Lovely day today so he's probably basking with a beer admiring his handiwork.

Do the Arnotts make that much difference other than articulation? Mybe the Boge dampers make more difference to the ride quality?

Grrrrrr said:

He was going to do it himself. Lovely day today so he's probably basking with a beer admiring his handiwork.

Do the Arnotts make that much difference other than articulation? Mybe the Boge dampers make more difference to the ride quality?

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Arnotts don't make any difference to articulation unless you fit GENIII. Even then you need extended travel shocks and modified sensor arms.

wammers said:

Arnotts don't make any difference to articulation unless you fit GENIII. Even then you need extended travel shocks and modified sensor arms.

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Arnotts gave a noticably more supple ride in mine, of course that could be because the old bags were hard and knackered.
At the time I fitted Arnotts they came with a lifetime warranty, that made them worth the small extra cost. The warranty has been reduced to 2 years and the price difference to Dunlops is now greater so I probably won't bother with them next time.

Datatek said:

Arnotts gave a noticably more supple ride in mine, of course that could be because the old bags were hard and knackered.
At the time I fitted Arnotts they came with a lifetime warranty, that made them worth the small extra cost. The warranty has been reduced to 2 years and the price difference to Dunlops is now greater so I probably won't bother with them next time.

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My new Dunlops gave a different ride than the old Dunlops. Have never seen Arnotts in the flesh, but they look wider than the Dunlops so maybe use slightly less pressure, and are therefore a bit less harsh, don't know for sure though.

wammers said:

My new Dunlops gave a different ride than the old Dunlops. Have never seen Arnotts in the flesh, but they look wider than the Dunlops so maybe use slightly less pressure, and are therefore a bit less harsh, don't know for sure though.

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I was under the impression you were the expert on old bags.

Hmmm. Need to have a go in someone who has Arnotts fitted in theirs and compare and contrast!

Grrrrrr said:

Hmmm. Need to have a go in someone who has Arnotts fitted in theirs and compare and contrast!

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I would add that Arnotts appear to use a better quality bag material than the Dunlops, if you can find them at a small premium to the dunlops I would say they are worth the extra especially if you are keeping the car lo9ng term as I am. Dunlops last 7/8 years, I'm hoping the Arnots last longer and take me to the end of my driving life.

I changed ours on Saturday. Even though the old ones had plastic ends, not alloy, the rears were a pain in the arse to get out. The body had rusted round the top mount and stuck them in tight..

I ended up using and old wood chisel to slice the tops off. They then dropped out easily.

I now suspect the compressor is a bit buggered because it now takes about 4 or 5 minutes to lift the car. Possibly it was driving 1 hour home with a holed air spring which killed it.