Aggressive Viscous Coupling

1
 
I have been driving around with the shaft out as VC was binding up on the 800k drive home when I bought the Syncro.  But might as well have bought a 2WD and wasn't learning anything about the problem so put the shaft back in and have been driving to work for about a week with the shaft back in.  I think the VC is only mildly aggressive but still a problem.  I think the best solution is a de coupler but money is tight at the moment and I may have to sell the vehicle so not keen to spend money at the moment.  I have been "managing" the problem in a number of ways and trying to work out ways to live with it.  Best technique I have found is to just drive straight but can't keep knocking down letterboxes and driving through people's backyards :)  Have found that stopping regularly such as at traffic lights relieves the wind up as does running two wheels on the dirt or on the grass every now and then. My tyres are 205R14 from 3 different brands so probably not identical diameters.  I would like to try 4 new tyres but once again not keen to spend big on tyres if I have to sell the vehicle especially since I suspect the problem will still be there.
Today, did the VC test; put rear end up on a trolley jack on level ground with 2" wood blocks in front of the front tyres and engaged G gear with engine idling.  On loading up the clutch the rear wheels begin to turn very slowly but I can't let the clutch out all the way without the front tyres climbing effortlessly over the wood blocks so I guess that is a fail :(.  Now am a bit more nervous about my "management" techniques although I reckon I have become very good at feeling the windup in the steering and the gearbox.  Has anyone else done the VC test and does anyone have a correctly functioning VC?  Anyone got any other techniques for living with the problem?  I am going to take the shaft out again until I come up with a solution; probably a decoupler,

Neil.
2
Does anyone know where to buy the VC fluid?


From: "neil smith jackthebearau@yahoo.com [Syncro_T3_Australia]" <Syncro_T3_Australia@yahoogroups.com>
To: yahoogroups <syncro_t3_australia@yahoogroups.com>
Sent: Thursday, 8 September 2016, 14:56
Subject: [Syncro_T3_Australia] Aggressive Viscous Coupling

 
 
I have been driving around with the shaft out as VC was binding up on the 800k drive home when I bought the Syncro.  But might as well have bought a 2WD and wasn't learning anything about the problem so put the shaft back in and have been driving to work for about a week with the shaft back in.  I think the VC is only mildly aggressive but still a problem.  I think the best solution is a de coupler but money is tight at the moment and I may have to sell the vehicle so not keen to spend money at the moment.  I have been "managing" the problem in a number of ways and trying to work out ways to live with it.  Best technique I have found is to just drive straight but can't keep knocking down letterboxes and driving through people's backyards :)  Have found that stopping regularly such as at traffic lights relieves the wind up as does running two wheels on the dirt or on the grass every now and then. My tyres are 205R14 from 3 different brands so probably not identical diameters.  I would like to try 4 new tyres but once again not keen to spend big on tyres if I have to sell the vehicle especially since I suspect the problem will still be there.
Today, did the VC test; put rear end up on a trolley jack on level ground with 2" wood blocks in front of the front tyres and engaged G gear with engine idling.  On loading up the clutch the rear wheels begin to turn very slowly but I can't let the clutch out all the way without the front tyres climbing effortlessly over the wood blocks so I guess that is a fail :(.  Now am a bit more nervous about my "management" techniques although I reckon I have become very good at feeling the windup in the steering and the gearbox.  Has anyone else done the VC test and does anyone have a correctly functioning VC?  Anyone got any other techniques for living with the problem?  I am going to take the shaft out again until I come up with a solution; probably a decoupler,

Neil.


3
Neil,

An aggressive VC is excellent for off-roading.

You just need a de-coupler for when you dont need 4WD.

I would leave it as is and get the de-coupler from (my preference) AA transaxle.

They make a good product and the Aussie Dollar to US dollar conversion is not too bad.

Cheers,

Skot

On 8/09/2016 2:56 PM, neil smith jackthebearau@yahoo.com [Syncro_T3_Australia] wrote:
I have been driving around with the shaft out as VC was binding up on the 800k drive home when I bought the Syncro. But might as well have bought a 2WD and wasn't learning anything about the problem so put the shaft back in and have been driving to work for about a week with the shaft back in. I think the VC is only mildly aggressive but still a problem. I think the best solution is a de coupler but money is tight at the moment and I may have to sell the vehicle so not keen to spend money at the moment. I have been "managing" the problem in a number of ways and trying to work out ways to live with it. Best technique I have found is to just drive straight but can't keep knocking down letterboxes and driving through people's backyards :) Have found that stopping regularly such as at traffic lights relieves the wind up as does running two wheels on the dirt or on the grass every now and then. My tyres are 205R14 from 3 different brands so probably not identical diameters. I would like to try 4 new tyres but once again not keen to spend big on tyres if I have to sell the vehicle especially since I suspect the problem will still be there.
Today, did the VC test; put rear end up on a trolley jack on level ground with 2" wood blocks in front of the front tyres and engaged G gear with engine idling. On loading up the clutch the rear wheels begin to turn very slowly but I can't let the clutch out all the way without the front tyres climbing effortlessly over the wood blocks so I guess that is a fail :(. Now am a bit more nervous about my "management" techniques although I reckon I have become very good at feeling the windup in the steering and the gearbox. Has anyone else done the VC test and does anyone have a correctly functioning VC? Anyone got any other techniques for living with the problem? I am going to take the shaft out again until I come up with a solution; probably a decoupler,

Neil.

--
Best regards, Scott Pitcher SPB Consulting
4

I agree with Skot. The only way to go.  Peter from Port

5
Dear Neil,
check the rolling radius or the circumference  of each of your tyres.
One tyre significantly over/under size compared with the rest can engage the VC.
I’ve got this problem myself at present because I delayed a tyre rotation.
For the time being my decoupler is saving the day.
Peter





On 8 Sep 2016, at 2:56 PM, neil smith jackthebearau@yahoo.com [Syncro_T3_Australia] <Syncro_T3_Australia@yahoogroups.com> wrote:



  
I have been driving around with the shaft out as VC was binding up on the 800k drive home when I bought the Syncro.  But might as well have bought a 2WD and wasn't learning anything about the problem so put the shaft back in and have been driving to work for about a week with the shaft back in.  I think the VC is only mildly aggressive but still a problem.  I think the best solution is a de coupler but money is tight at the moment and I may have to sell the vehicle so not keen to spend money at the moment.  I have been "managing" the problem in a number of ways and trying to work out ways to live with it.  Best technique I have found is to just drive straight but can't keep knocking down letterboxes and driving through people's backyards :)  Have found that stopping regularly such as at traffic lights relieves the wind up as does running two wheels on the dirt or on the grass every now and then. My tyres are 205R14 from 3 different brands so probably not identical diameters.  I would like to try 4 new tyres but once again not keen to spend big on tyres if I have to sell the vehicle especially since I suspect the problem will still be there.
Today, did the VC test; put rear end up on a trolley jack on level ground with 2" wood blocks in front of the front tyres and engaged G gear with engine idling.  On loading up the clutch the rear wheels begin to turn very slowly but I can't let the clutch out all the way without the front tyres climbing effortlessly over the wood blocks so I guess that is a fail :(.  Now am a bit more nervous about my "management" techniques although I reckon I have become very good at feeling the windup in the steering and the gearbox.  Has anyone else done the VC test and does anyone have a correctly functioning VC?  Anyone got any other techniques for living with the problem?  I am going to take the shaft out again until I come up with a solution; probably a decoupler,

Neil.



6

Yes, lots of things can affect the radius, not just tread wear, tire pressure, tire construction (if they are all different brands), even tire age.

These all however affect binding up while driving, they won't affect the test you did, so it would seem it is a little tighter than standard and will be loading up you GB.


how you fix it is really up to what you want to do with it. If you want the added safety of permanent AWD, the VC will need repairing. If you do get new fluid, don't; forget to replace the seals!

If you are happy with 2WD and 4WD only when off road, the decoupler is the way to go and leave the VC as is.


Richard



---In Syncro_T3_Australia@yahoogroups.com, <peter@...> wrote :

Dear Neil,
check the rolling radius or the circumference  of each of your tyres.
One tyre significantly over/under size compared with the rest can engage the VC.
I’ve got this problem myself at present because I delayed a tyre rotation.
For the time being my decoupler is saving the day.
Peter





On 8 Sep 2016, at 2:56 PM, neil smith jackthebearau@... [Syncro_T3_Australia] <Syncro_T3_Australia@yahoogroups.com> wrote:



  
I have been driving around with the shaft out as VC was binding up on the 800k drive home when I bought the Syncro.  But might as well have bought a 2WD and wasn't learning anything about the problem so put the shaft back in and have been driving to work for about a week with the shaft back in.  I think the VC is only mildly aggressive but still a problem.  I think the best solution is a de coupler but money is tight at the moment and I may have to sell the vehicle so not keen to spend money at the moment.  I have been "managing" the problem in a number of ways and trying to work out ways to live with it.  Best technique I have found is to just drive straight but can't keep knocking down letterboxes and driving through people's backyards :)  Have found that stopping regularly such as at traffic lights relieves the wind up as does running two wheels on the dirt or on the grass every now and then. My tyres are 205R14 from 3 different brands so probably not identical diameters.  I would like to try 4 new tyres but once again not keen to spend big on tyres if I have to sell the vehicle especially since I suspect the problem will still be there.
Today, did the VC test; put rear end up on a trolley jack on level ground with 2" wood blocks in front of the front tyres and engaged G gear with engine idling.  On loading up the clutch the rear wheels begin to turn very slowly but I can't let the clutch out all the way without the front tyres climbing effortlessly over the wood blocks so I guess that is a fail :(.  Now am a bit more nervous about my "management" techniques although I reckon I have become very good at feeling the windup in the steering and the gearbox.  Has anyone else done the VC test and does anyone have a correctly functioning VC?  Anyone got any other techniques for living with the problem?  I am going to take the shaft out again until I come up with a solution; probably a decoupler,

Neil.



7
Slightly different tyres I think led to a gearbox rebuild for me.  I thought my VC was passive, did little to nothing offroad, but not completely passive obviously - when I lost a rear half shaft it would slowly inch forward from the passive vc, and I think that was enough overtime to help destroy the gearbox.  Expensive learning curve.  A decoupler and aggressive VC now is great, 2wd all the time until off road, or the AWD safety I also pull on if heavy rain.  Unless very closed match diameter on tyres I would run 2wd unless a lot of slip available on the surface being driven on.
8
Hi Neil,  Can you call me...   0411 202 895

Peter