4x4 front wheel drive not working

[David Colbourne]

Hi
I have a SGL5 4X4 2.5D. First snow and icy roads of the winter and found out front wheel drive is not working-and finished up off the road. Ali at local garage checked today and topped up oil but no drive from transmission box to front wheels-any ideas what could be wrong and how to fix?
Many Thanks
David

[Northern Bongolow]

look on the internet on how to check a viscus coupling. it doesnt quite work how you think it might.

[Bob]

Do bear in mind that although the stickers say Full Time 4WD this is not actually the case.

The viscous coupling on the gearbox detects a rear wheel loosing traction then applies some of the drive to the front wheels as required, they're not actually driven all the time.

[Tony x]

Some convert the 4WD to 2WD - wonder if this has been done to yours

[hijimhere]

What makes you think the loss of control is related to the driven axles? Four wheel traction is only achieved on vehicles that have limited slip (racing saloons) or locked diffs. In the absence of diff locks most 4 x 4 s only have one driven wheel on each axle. These types of vehicles are mainly military off roaders.

[teenmal]

What makes you think the loss of control is related to the driven axles? Four wheel traction is only achieved on vehicles that have limited slip (racing saloons) or locked diffs. In the absence of diff locks most 4 x 4 s only have one driven wheel on each axle. These types of vehicles are mainly military off roaders.

Hi Jim, the front Differential is driven from the chain in the transfer box.

[briwy]

What makes you think the loss of control is related to the driven axles? Four wheel traction is only achieved on vehicles that have limited slip (racing saloons) or locked diffs. In the absence of diff locks most 4 x 4 s only have one driven wheel on each axle. These types of vehicles are mainly military off roaders.

Under normal (ie non slippy) circumstances drive will be from both both wheels on an axle with a diff. The diff compensates for the different wheel speeds when going round bends. A diff lock on a Bongo would be lethal.
Some Bongos do have a limited slip diff on the rear, identified by a sticker or putting the VIN into the Russian info thingy will tell if it has.

[Ian]

If this is the Bongo that's in a garage on the Isle of Skye, then the mechanic has checked and the vehicle does not have LSD.

[hijimhere]

Thanks for the info on the drive for the front diff. As the owner of many a 4x4 namely Frontera, Maverick, Series ll and lll Land Rover and prior to the Bongo a Freelander. The Freelander has the viscous coupling fitted on the rear propshaft. The principle is I understand the same with all viscous couplings to distribute the power when conditions require front/rear/front and so on.

However the two Series ll and lll both had the ability to "lock" the front differential. This condition resulted in both front wheels rotating at the identical speed (auto locking was intoduced later). So irrespective of turning left or right or speed travelled both wheels would attempt to rotate at an identical speed.

However, in my Freelander, Maverick and Frontera there was no differential lock fitted. So irrespective of turning l terms eft or right or speed travelled the differential would operat normally. That is to say turning left would allow the left wheel to turn slower than the right wheel.
The effect of the differential if you were in mud or on ice with wheel slip would be to allow one wheel to be driven while the wheel opposite would be stationary (an extreme situation.

To observe the effect watch any so called 4 wheel drive vehicle get out of trouble in a field. If you witness both wheels on the one axle rotating equally the vehicle has diff locks. On the other hand if you see one wheel spining furiously and the other barely spinning at all you are viewing a vehicle which does not have any diff locks. You are advised not to use any vehicle with the diffs locked for any distance on tarmac roads.

You simply cannot drive all four wheels unless you have locked the front and rear differentials - regretably our Bongos are not fitted with diff locks.

I hope I have clarified my earlier post without causing any upset.

[Muzorewa]

I'm sure no upset meant or taken.

You're wrong on the series II and III Landy though, they have free diffs on both axles and are part-time 4WD, when you engage 4WD the front & rear axles are locked together so the front & rear props turn at the same speed. But you only need to lose traction to one wheel on each axle to be stuck, being 'cross-axled' is an easy fail on trials. You can get after-market diff-locks for one or both axles but only serious off-roaders would fit them.

When you see a '4WD' floundering in mud, whether you see one or two wheels spinning furiously depends on which ones have lost grip, you could lose traction to both wheels on one side or on diagonal corners, depends on the ground conditions.

For a proper off-roader, you need something like a Mercedes G-Wagon (or Unimog) that have three diffs and they're all lockable. Then you have to be properly stuck to require assistance.

Next best thing is a 4WD Bongo with LSD on the back axle. With the good weight distribution from the mid-engine layout and drive to at least three wheels, you should struggle to get stuck. Ground clearance is the one thing that stops a Bongo being a proper off-roader

[ELZE]

Unsure if it is possible on a Bongo but if you could fit one of these bad boys?

http://www.ebay.co.uk/itm/Land-Rover-Di ... 27cf9a783a

[helen&tony]

Hi
The short answer...NO
If you want something better, get a second-hand LSD....or buy a Landie for those awkward moments....or a Unimog for even awkwarder moments....and you can upgrade to a Sno-Cat
Cheers
Helen

[briwy]

4wd Bongo, limited slip rear diff, winter tyres, No problem



Took a run a anything deeper than a foot and barged through.

Michael (Lone Ranger) took a similar route in his Bongo actually towing a caravan and got through

Come on snow.

[helen&tony]

Hi
The Bongo's pretty good in a foot or thereabouts of snow, but it's never going to be great....Ground Clearance. When the going's tough, I take the Jeep...Command-Trac and rear LSD...
Usually, though, I refrain from driving in the worst conditions, as the Bulgarians are real cowboys on the road, usually 3 sheets to the wind on Rakiya, and slumped in a ditch somewhere....I value my life too much to mix it with them!
Cheers
Helen

[Dodgey]

How does the power distribution work on the Bongo 4x4? I'm buying chains, and I'm assuming for the front (traction and steering, and best braking), unless there is some weird power distribution I don't know about.

I don't have the LSD model.