2wd and 4wd and the mysterys of how to use?!.......

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Scc28
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hi im new to the g world, ive got my first g a 1984 230ge swb. Ive been reading about how and when to change form 2wd to 4wd high but im confused by the transmission binding issue, from what i gather rightly or wrongly you can use 4wd high in a straight line and binding only occurs when going round corners is this correct? so in theory if you road was completly straight binding or windup would never occur? just dont want to blow up my gearbox!!!

Any help in simple terms welcome!

cheers simon

Quercus
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Re: 2wd and 4wd and the mysteries of how to use.......

When drives to both axles are engaged in a selectable or "part-time" set up like the 460 G, they have to rotate at the same speed. In a straight line, this is not a problem so the transmission does not bind or "wind-up". However, as soon as you turn the front wheels and the vehicle prescribes a curved path, the wheels on the front axle have to travel further than the wheels on the rear, just as the outside wheels on both axles go further than those on the inside. In fact, all four wheels have to travel at different speeds. Within the individual axles, these varying rotational speeds are taken care off by the differentials (it's their main function), but the axles are mechanically locked together without the benefit of a differential so the transmission starts to fight itself and wind-up occurs. On a dry road or high traction surface, this is very pronounced with the sterring stiffening up and the vehicle being reluctant to progress. On a slippery surface the discrepancies are lost by wheel slip/spin. In a permanent four wheel drive system such as the 463 model, or any 4WD that sports a centre inter-axle differential unit for that matter, this binding does not happen as the diff performs its function and takes care of it, unless you select diff- lock, of course, at which point it behaves just like a part-time system in 4wd. In terms of off-road performance, there is no difference between a locked permanent drive system and a selectable or part-time system like yours in 4WD.

In reality, assuming your vehicle's transmission is sound, you are unlikely to do much damage if you inadvertently leave it in 4WD high range on the road, specially if it is wet. It will very quickly become obvious to you that something is not right if it's dry. You may have difficulty de-selecting 4WD if the transmission has wound-up a bit. If so, just steer left and right a few times, if appropriate, or, failing that, run the wheels on one side of the vehicle or another on to a soft verge. This will allow slip to take place and relieve the wind-up so you can revert to 2WD. In a severe case of wind-up, and if all else fails, jack one front wheel off the ground so the torsional forces are released. It is unlikely you will ever have to do this, and I haven't since my youthful days with old Land Rovers, Gipsys and Bedford RL's. Have fun.
Hope that helps. :)

foneman
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Re: 2wd and 4wd and the mysterys of how to use?!.......

very well put mr Quercus

Scc28
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Re: 2wd and 4wd and the mysterys of how to use?!.......

many thanks for that, so basically if its snowy or slippery engage in the straights and disengage for the bends? or is that to simplistic a view?

twodogs
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Re: 2wd and 4wd and the mysterys of how to use?!.......

as long as the track , trail , or road will allow a bit of slip ie,graval , wet, mud you will be able to use hi-range 4x4 including bends .
Twodogs

marcus
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Re: 2wd and 4wd and the mysterys of how to use?!.......

No,
If conditions merit the engagment of 4WD , leave it engaged for the corners, but remember to disengage ASAP when conditions improve, as Quersus mentioned you should feel the "windup" requiring an extra bit of effort on the steering input required, or the steering feeling "strange".
I once apon a time rallied a wee cut wing around the backroads of Stirlingshire, in the autumn, the roads were wet and there were quite a few fallen leaves, she went MUCH better with 4WD engaged, but then I was probably only on three wheels going round the corners, OH and it was an Army vehicle, and it never done a bit of harm.
So its all down to judgement.
Cheers,
Marcus

peter perfect
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Re: 2wd and 4wd and the mysterys of how to use?!.......

guys dont know if you noticed but he lives in manchester, so my advise is leave in 4wd, cos, IT ALWAYS FCUKING RAINS IN MANCHESTER, well every time I been there it has :shock: .

twodogs
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Re: 2wd and 4wd and the mysterys of how to use?!.......

:D

Scc28
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Re: 2wd and 4wd and the mysterys of how to use?!.......

only 90% of the time the other it snows so a perfect vehicle would be happy on any advice on off road driving using diff locks etc, is there no other north west g owners out there? and its not manchester its just to the north sunny bolton!!!!

LEEU
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Re: 2wd and 4wd and the mysterys of how to use?!.......

I'm in St George, close to Abergele. +- 1hour away. if you want to come and test all these 4x4 gadgets, I live on a 7000 acre farm....

Scc28
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Re: 2wd and 4wd and the mysterys of how to use?!.......

cheers leeu, may take u up on that?! would be good to have some one local who knows about g's. need to do my rear light panels any experience in this? cheers simon

marcus
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Re: 2wd and 4wd and the mysterys of how to use?!.......

That will all be arable then LEEU, all 7000 acres ?
Cheers,
Marcus

LEEU
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Re: 2wd and 4wd and the mysterys of how to use?!.......

Most of it Marcus. I do the deer culling on a lot of farms in the area, giving me access to a few interesting places. Martin (Buckelec) has been here, maybe we must do a camp weekend.

scouse g
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Re: 2wd and 4wd and the mysterys of how to use?!.......

He's got the best house on the estate (veiw included). LEEU doesn't know he's born! I've been there.....it's fcuking mavellous! If there was any Texan's around they'd pay to cull, you'd be a millionare. he he !