Thread: Mechanics

Sorry mate, didn’t realise yu still had the driveshaft park brake setup. I thought you had drum mounted set up from the imbalance part. Ignore my post. Them driveshaft cardan setups are crap, and deadly, same as the stupid telmar brake system they use on some euro trucks. I have a few horror stories from their failures.

Originally Posted by jamie

Sorry mate, didn’t realise yu still had the driveshaft park brake setup. I thought you had drum mounted set up from the imbalance part. Ignore my post. Them driveshaft cardan setups are crap, and deadly, same as the stupid telmar brake system they use on some euro trucks. I have a few horror stories from their failures.

Telmar's are only a retarder, not a foundation brake

Originally Posted by No.3

Well I guess in their defence, if they fark them on the brake machine it is likely that they wouldn't have worked when needed. The weakness as it is (although you are relying on one drum, with two shoes rather than on the wheels with four shoes and two drums which is 50% more redundancy) is in the driveshaft and pinions - that's where the failures seem to happen with them. The driveshaft either unwinds itself with the sudden shift from load side to unload (it was explained to me as similar to trying to grab reverse at 30Km/H and slowly releasing the clutch) which causes the pinions to flop about. If there is any wear and play the things take a hate to you most ricky ticky.

The problem is that they are a stationary holding brake, so applying them on the brake rollers doesnt even simulate how they would be used in real life.
I have seen trucks roll away with the cardan applied, one wheel on the road, other wheel on the grass. it spun the wheel on the grass forwards and just rolled away down the hill

Yep exactly, there was a prang in Tauranga like this a while back, the truck skidded down a grass hill with alternative wheels rolling and skidding... There should at a minimum be a limited slip diff or similar on those setups. Or a driver that knows they cannot leave the cab or must fit a hold-down to the brake pedal if the have to park on unformed surfaces and get out and leave the truck...

Where the damage risk on testing them on the rollers is on the dynamic reversal on the driveshaft pinions - very correct in saying that that is not what they do in real life. Although if they do explode something on the rollers likely the setup was not warrantable anyway.

There has been a lot of talk on the motorhome forums about cardan brakes and failing COF's

Originally Posted by Happy Jack

There has been a lot of talk on the motorhome forums about cardan brakes and failing COF's

Yes. They have to be in supremely good condition to now pass the test. Pretty much a full teardown, clean up and sand the drum, brakeclean, new shoes, adjust etc etc.

How to the GQ patrols and safaris get on now? I haven't talked to anyone who's had any issues which sort of surprises me.

But it's bollocks isn't it.
Those cardan/driveshaft brakes are for parking only. Not an emergency brake.
They will never be as efficient as even shabby back drums let alone modern disc brakes.

Originally Posted by No.3

How to the GQ patrols and safaris get on now? I haven't talked to anyone who's had any issues which sort of surprises me.

Its currently only for COFs, not WOFs. Thank f@ck!