brake fluid life

[Alistair-49qrn]

Local Porsche centre is about to take £540 for a minor service on my other half's 718, they called me and say Porsche recommends brake fluid replacement every two years at £150.

I have usually reckoned on 3-5 years on VW, BMW and suchlike so I asked if it was a mandatory service item and they said no and mumbled warranty blah blah. I suppose I could get a local specialist like eporsch to do it for less - a litre of dot 4 is about £10 and it probably only takes an hour?

Back in the day people used to test brake fluid to see if it was still good, does anybody do that now?

[Twinfan]

It's a 2 year/20,000m replacement schedule and if your OPC follows the fixed servicing pricing system then it should be £95. That's what I paid last month for my 981 and my OPC as part of the first service (£590 for service and brake fluid change).

Welcome to Porsche ownership - it's not a cheap thing.

Edited by Twinfan on Wednesday 23 May 10:38

[gwsinc]

I'd say every 2 years is about right. Brake fluid absorbs water readily so if it's been standing for a while or kept outside condensation can make its way into the fluid and make the brakes a little spongey. If the brake lines are older and the seals less than perfect this will accelerate the process.

I had mine done for £95 at a specialist, still expensive but better than shelling out £150!

[Porsche911R]

gwsinc said:

I'd say every 2 years is about right. Brake fluid absorbs water readily so if it's been standing for a while or kept outside condensation can make its way into the fluid and make the brakes a little spongey. If the brake lines are older and the seals less than perfect this will accelerate the process.

I had mine done for £95 at a specialist, still expensive but better than shelling out £150!

"condensation can make its way into the fluid " how on a 2 year old car can condensation make its way into the fluid ?

A brake fluid flush every two years or 20,000 miles is really a precautionary measure to be on the safer side.

but yes I have only been charged £95 from my OPC.

[EGTE]

My Indy tests my fluid every year. Think my fluid has taken on absolutely no water in 4 years , so why change it, they say? My car is garaged.

[Pope]

Given the propensity for the bleed nipples to seize in the calipers I would stick to the 2yr bleed schedule at the very least it 'might' stave off the possibility.

The quality of the fluid can drop - and usually at the caliper rather than the reservoir (however marginal).

Edited by Pope on Wednesday 23 May 22:17

[IREvans]

Alistair-49qrn said:

Local Porsche centre is about to take £540 for a minor service on my other half's 718, they called me and say Porsche recommends brake fluid replacement every two years at £150.

I have usually reckoned on 3-5 years on VW, BMW and suchlike so I asked if it was a mandatory service item and they said no and mumbled warranty blah blah. I suppose I could get a local specialist like eporsch to do it for less - a litre of dot 4 is about £10 and it probably only takes an hour?

Back in the day people used to test brake fluid to see if it was still good, does anybody do that now?

I'd suggest getting it done, just try and negotiate on the price...

Any brake system cannot be a 100% seal from the atmosphere - as brake pads wear, the fluid level drops in the reservoir drawing in air containing moisture, which is absorbed into the brake fluid. The water 'could' cause premature corrosion of various components within the braking and ABS system....its good practice to replace the fluid, flushing clean fluid throughout the braking system, and gives the opportunity to loosen each of the 8 bleed nipples.

[R129 300SL]

IREvans said:

I'd suggest getting it done, just try and negotiate on the price...

Any brake system cannot be a 100% seal from the atmosphere - as brake pads wear, the fluid level drops in the reservoir drawing in air containing moisture, which is absorbed into the brake fluid. The water 'could' cause premature corrosion of various components within the braking and ABS system....its good practice to replace the fluid, flushing clean fluid throughout the braking system, and gives the opportunity to loosen each of the 8 bleed nipples.

I would agree if they indeed did it that way.

You may find that they do it by opening the nipple furthest away and flushing through with some sort of pressure device:

[Pope]

Approved method is using pressure bleeder; flush and bleed all four calipers inside and out and the clutch slave cylinder (if it's a manual).

[IknowJoseph]

Pope said:

Given the propensity for the bleed nipples to seize in the calipers I would stick to the 2yr bleed schedule at the very least it 'might' stave off the possibility.

The quality of the fluid can drop - and usually at the caliper rather than the reservoir (however marginal).

Edited by Pope on Wednesday 23 May 22:17

This is 100% the advice I've been given. My fluid has been tested, and is not full of water, but will be changed as per the schedule because the nipples seize when it doesn't get changed. I know this because I changed the fluid for the first time in years and the nipples snapped in the caliper.

[Pope]

Aware that this may be a slight thread derail, but worth mentioning the same if the question arises regarding spark plug replacement at 4yrs......

Low mileage so 'they'll be alright' or risk a cylinder head repair??

[ParkerG]

I changed my fluid a year after my OPC apparently did, it was rather dirty and I'm not convinced they actually did it!

Pope said:

Approved method is using pressure bleeder; flush and bleed all four calipers inside and out and the clutch slave cylinder (if it's a manual).

What PSI do Porsche recommend?

[Pope]

2 bar / 30psi

[ParkerG]

Pope said:

2 bar / 30psi

Thanks, that seems incredibly high though.

I think my pressure bleeder warns not to go above 25, in fact I did bled mine with 10-11PSI.

[Pope]

2 bar in the workshop manual; not seen one pop a reservoir off yet

At 10psi the OP might be charged 2 hrs!!