T4 syncro bearing driveline problem

[Jezza]

Hi there. I have a bearing type sound in my 2000 model LWB Syncro (180,000 kms) that has been getting progressively worse over the last few months. I thought it was the wheel bearings, having experience with other vehicles but took it to a generic mechanic today and he thinks it may be play in the driveshaft going to the back wheels. There are two mounts for the shaft along its way to the back wheels. The front one has 2-3mm of play. The rear one has none. Me thinks my shaft could be whirling as well as spinning and making the bearing type noise. Has any one had experience with this? Jezza

[Seano]

Jezza....play in the rear main driveshaft couplings is something of a necessity. Both of mine have some measure of play. But that is tempered by the resistance of the rubber mounts. If yours move without that resistance then I'd agree that the coupling might have a problem. But I truly doubt it.

Is the noise you hear speed matched to the driveline or the engine?

[Jezza]

Hi Seano. Sorry it has taken while to get back to you.
There is play in each rubber mount but it is just in the rubber, no slop. As you said probablr fairl normal allowinf for engine movement , flex. etc.. But in the first front tail shaft, just where it joins into the next shaft before the front mount, there is some play in what I assume is some kind of CV joint or spline. I reckon it would be a CV joint. There would be at least 1-2 of clearance.
I took it to another mechanic the other day. He reckons it could be the rear diff. He sat in the back on a test drive and could hear the noise coming form the rear. It is a real whine, a bearing noise. To answer your question, it is definitly the driveline as it gets louder the faster you go. It had a major service done by Volkswagen in Perth recently and all fluids were replaced. I have done 50,000km since. The mechanic checked the oil in the diff. It was full and looked fresh. I have jacked up all wheels and spun each around by had. They all felt fine, not tight or any play in the bearings. Hmmm. any ideas.

[Seano]

Shaft play results in a different sound (thunktathunkatathunkata...) than diff whine (like what one can hear in the back seat of a Ford taxi).

If the rear diff is the culprit.......then you are possibly up for a rebuild. Which will be expensive. See if you can find a driveline or gearbox specialist to have a run at it first.....

[Jezza]

Yes, I definetely remeber the whine of the Ford taxis. This is more like the sound my machine makes. It is constant from a standing start getting louder as you drive faster. I live in Geraldton WA. There is no VW dealer here. I think the best way is to take it VW first maybe in Perth. What do you think?

[jets]

I hope you don't have to replace the crown wheel & pinion.
T4 Syncro rear diff - repair or replace? - The Brick-yard