Limited Slip Diff?

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Steptoe
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Limited Slip Diff?

Post by Steptoe » Mon Jun 23, 2014 10:41 am

When pulling away from a junction, or turning sharply (either way) with a moderate throttle, The inner rear wheel 'scuffs', as though the diff is locking up. In normal use, however, it drives fine with no obvious problems with turning or pulling as it would if the diff were locked solid.

Is this a 'feature' of the Limited Slip Diff which is on some models? Or does this suggest a potential problem? I'm having the transfer box levels checked as we speak, as well as various other jobs, so this may sort it but I wondered if anybody else is aware of this.
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Muzorewa
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Re: Limited Slip Diff?

Post by Muzorewa » Mon Jun 23, 2014 10:51 am

Sounds normal, ours does that and has done for the last 250,000km.
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teenmal
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Re: Limited Slip Diff?

Post by teenmal » Mon Jun 23, 2014 11:44 am

Steptoe,You need to get the Viscous Coupling checked ASAP.
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Re: Limited Slip Diff?

Post by Steptoe » Mon Jun 23, 2014 12:32 pm

teenmal wrote:Steptoe,You need to get the Viscous Coupling checked ASAP.
Couldn't this be a symptom of a GOOD viscous coupling? As the weight lifts off the back wheel, it tries to spin? It doesn't do this unless I give a bit of throttle leaving a junction or turning up a hill, which would lift the weight off the inner wheel.

I've seen reports of how to test the VC. Lift the front wheel and try to turn it. If it spins easily, then there is a problem. If it takes 30 seconds to turn with the defined torque, then VC is good. Last time I had the front wheel up, it was certainly an effort to turn it (although it did turn), so this was not a problem as far as I could tell.
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Simon Jones
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Re: Limited Slip Diff?

Post by Simon Jones » Mon Jun 23, 2014 12:47 pm

VC comments are only relevant if 4WD which has yet to be established. I've had 2WD & 4WD which both exhibit same characteristic of slight scrubbing on full lock.
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Re: Limited Slip Diff?

Post by teenmal » Mon Jun 23, 2014 12:50 pm

Simon Jones wrote:VC comments are only relevant if 4WD which has yet to be established. I've had 2WD & 4WD which both exhibit same characteristic of slight scrubbing on full lock.

I'm having the transfer box levels checked as we speak
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Re: Limited Slip Diff?

Post by Simon Jones » Mon Jun 23, 2014 1:04 pm

Reading thru Steptoe's first post: http://www.igmaynard.co.uk/bongo/forum/ ... 46#p625846 he does appear to be 4WD so transfer box should be on the checklist. He also mentioned uneven tyre wear which required a new set at the front. Mixing tyres of different rolling circumferences does open another potential can of worm. Even the size tyres from 2 manufacturers can have differing circumferences which can compound any differences caused by mixing new with part-worn.
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Re: Limited Slip Diff?

Post by Steptoe » Mon Jun 23, 2014 2:36 pm

Yep, 4wd.
The scrubbed tyres were fitted from another bongo when I collected it, as the originals were apparently worn. Visibly they looked ok, the wear was evident to the touch though when I looked into the high level of noise and vibration. Since I fitted new front tyres, it's been transformed. I doubt that wear is attributed to my van. Currently drives fine. The only question relates to pulling away on full lock under power. Other than this, there is no noticeable issue. I am aware of what a locked diff feels like as I previously had a Pajero with centre diff lock. It was horrible to drive on a hard surface when locked, and the bongo is nothing like that.
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Muzorewa
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Re: Limited Slip Diff?

Post by Muzorewa » Mon Jun 23, 2014 2:46 pm

If it's anything like ours, you'll find that the fronts will be good for ages and then you'll get uneven wear on the inside edges and the noise & vibration will be back. New tyres and it's like driving a different vehicle. Still 30-40k km on a set.
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Re: Limited Slip Diff?

Post by Steptoe » Mon Jun 23, 2014 7:36 pm

Apparently, transfer box was low so all topped up now. Will pick up tomorrow when the other jobs have been finished.
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