Club 80-90 Forums

http://cgi.ebay.co.uk/vw-syncro-t2-t3-z ... dZViewItem good price too!!!!!!!!!

Every few months this person puts up a few decouplers.They are not complete kits though.No pipe work or valves with them.
Good prices though.

Uh oh... you mentioned the "D" word........

Only suitable for moving vehicles.

not contradicting previous rants are yer!!!

Not long now... finish in Belgie end of the month... then try the French red tape again...

I'm not saying they're the way forward, but there's no point fitting them to a non-moving vehicle now, is there?

nope... but I could polish it and put it on the mantlepiece

Please excuse my ignorance............but what exactly is a decoupler?

It offers fixed drive or 2WD, forsaking all of the lovely effects of full-time 4WD for a drivetrain that lacks any centre differential effect which is offered by the VC as standard.

It effectively stops you benefiting from the 4WD on road as your vehicle will suffer transmission wind-up (which is different to forum wind-up).

Only really suitable for America where you drive in straight lines for so many hours you can't remember what a corner is.

VC and fun on roundabouts for me every time.

For further stuff look here

A decoupler is a device which disconnects the drive from the gearbox to the front differential unit by means of a vacuum assisted control operated from the dashboard.

When fitted at the factory, the vehicles did not have a Viscous Coupling and when the vehicle was used on hard surface, only 2WD was used. Once in the mud or snow, the Decoupler was activated to give 4WD and no slip between front and rear wheel speed. Note, doing this on a hard surface could damage the gearbox, front diff or any of the transmission system.

The setup can be bought and used either with or without a Vicous Coupling now so that you could save the life of your VC and run in 2WD daily.

Usually the VC is replaced by a straight drive piece when a Decoupler is fitted.

If you have a Syncro with diff locks, you'll see that on the diff lock control panel, there is space for 3 control knobs. The Decoupler uses the centre of these.

MG

Doesn't it fit with the VC efectively allowing you to "drop the prop" without actually having to get out of the van or indeed even stop the engine?

Certainly the stuff behind the link would suggest that you can choose to also replace the VC.

"Forum Windup" heheh

it *could* Euan, but people offer billet shafts to replace the VC, eliminating that useful differential effect.

dumb question alert

erm . .reading all that, and before anyone starts I'm not advocating spending so much cash on something you might need once (i.e if the VC failed closed), am I right in thinking you can run a de-coupler with the VC still fitted?

An added benefit is the protection it provides the viscous coupling by preventing damage (churning) when driving on twisty roads or the freeway in the heat for prolonged periods

and is there a general concensus of opinion as to which is more harmful for the VC, leaving it to do it's job under normal usage or dis engaging it and letting it 'rest'?

(ok, I was typing mine while others replied)

It takes in excess of 10 years, or 100-200,000miles for a VC to fail. Not bad for a sub-£400 investment.

I think in the period of 100-200,000miles or ten years there is likely to be at least one incident where you'd want the benefits of 4WD when you weren't expecting them (wet roads etc). At precisely this unexpected point your decoupler becomes a very large waste of money and quite possibly your insurance premiums go up.

Apparently they improve the vehicle's performance in sand, which isn't terribly useful unless you're going to a desert, which some people on here are doing.