VW t4 syncro troubleshoot

**Racemag** · 09-03-2020, 09:53 AM

My T4 syncro (470,000km on the clock) has been trouble-free for a long time, but I recently felt a bit of a 'clunk' when taking off from a stand still and a whine from behind the cabin at speed. Now I'm getting a vibration at 80kph. Initial thought was CV in the tailshaft, but I've just been under the car and it seems OK. Front driveshafts are worn, but seem sound. What else?
I'm about to check the rear diff.
I'm reluctant to spend much to fix it as I was going to sell it in the near future - we've had our fun with it and it's done a great job for us and the LPG conversion has made it a very cheap car to own. Sow what do I check from here?

**Racemag** · 09-03-2020, 10:09 AM

Well back in the air and the rear diff is fine. Rear driveshafts are OK too. Checking wheel bearings.

**Rebuild** · 09-03-2020, 10:23 AM

are these auto or manual?
I know the t4 autos give trouble

**Racemag** · 09-03-2020, 11:15 AM

Originally Posted by Rebuild

are these auto or manual?
I know the t4 autos give trouble

Manual. Gearbox is good. Engine starts and runs well. Rear diff makes a little noise when I spin one wheel quickly (the other going the other way) but really that's not the issue on the road at 80kph.

**LogicprObe** · 09-03-2020, 06:03 PM

Mine was making a weird noise before the driver's side CV decided to collapse.

**Seano** · 09-03-2020, 07:42 PM

Sounds like a bit of driveline lash. Which basically makes it CV joints or the central driveshaft. And there's a couple of wear points in the central driveshaft couplings. My T4 Syncro is a lwb so it has two shafts so three couplings and two bearings.

The last time we did CVs (last year, rear) my mechanic managed to source the joints separately and very economically and he rebuilt the rear driveshafts.

Incidentally, the central driveshaft bearings are almost the same as those found in the European version of the LT from the mid 90s...so they can be found very cheaply on eBay whilst they are unavailable for the T4. They just need some cutting off a small shroud near the main bearing...

**Racemag** · 09-03-2020, 09:27 PM

It is a DOKA, so LWB with the long shaft. There's play in everything, but then I'd expect there to be some. I could not spot anything obviously wrong so it's either off to the mechanic or sell it off cheaply.