4x4 Action Group

Manual vs Auto off-road

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XJ Junkie
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#46

Post by XJ Junkie »

ThysleRoux wrote:Neil, if the axles and transfer case are locked, braking on even only one wheel will result in the force distributed equally between all wheels. If only the TC is locked (difflock or bakkie type TC) the force will be equally applied to the front and rear axles
This simply isn’t true.
Disclaimer: Uninformed, no research, just very strong opinions

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ThysleRoux
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#47

Post by ThysleRoux »

Please elaborate on how you justify this claim? It's simple physics.

If the diff is locked, the wheels (or in the case of a center diff lock/ "bakkie" TC in 4x4, the prop shafts) are locked together and any force applied to the one side of the diff will be transferred to the other side.
I refuse to be POLITICALLY CORRECT to impress others - Deal with it
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Sennin
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#48

Post by Sennin »

All depends if there is a front and rear diff-lock with center diff-lock engaged at once, then force will be transferred to all other wheels

but in the instance where you only have center diff-lock, and rear diff lock, but braking force is applied to only one of the front wheels, the story changes
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Reenen
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#49

Post by Reenen »

Sennin wrote:All depends if there is a front and rear diff-lock with center diff-lock engaged at once, then force will be transferred to all other wheels

but in the instance where you only have center diff-lock, and rear diff lock, but braking force is applied to only one of the front wheels, the story changes
Voertuie rem in albei voor wiele, nie net in een nie. Altans, padvaardige voertuie. As jou voertuig nie remme het nie, dink ek nie hierdie bespreking tel regtig nie.

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XJ Junkie
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#50

Post by XJ Junkie »

ThysleRoux wrote:Please elaborate on how you justify this claim? It's simple physics.

If the diff is locked, the wheels (or in the case of a center diff lock/ "bakkie" TC in 4x4, the prop shafts) are locked together and any force applied to the one side of the diff will be transferred to the other side.
If I were wrong, then the front wheels wouldn’t rotate under throttle throttle with the handbrake on, but they do.

Whilst it’s true that the shafts will turn at the same speed, wheel rotation depends on the terrain & is decided by the diff.

But the handbrake trick isn’t meant to stop the vehicle, just stabilize it.
Disclaimer: Uninformed, no research, just very strong opinions

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Sennin
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#51

Post by Sennin »

Reenen wrote:
Fri Apr 26, 2019 10:08 am
Sennin wrote:All depends if there is a front and rear diff-lock with center diff-lock engaged at once, then force will be transferred to all other wheels

but in the instance where you only have center diff-lock, and rear diff lock, but braking force is applied to only one of the front wheels, the story changes
Voertuie rem in albei voor wiele, nie net in een nie. Altans, padvaardige voertuie. As jou voertuig nie remme het nie, dink ek nie hierdie bespreking tel regtig nie.
tot jou ABS inskop en net een wiel rem terwyl die ander een probeer traksie kry...
It's not a car, It's not a truck, It's not just another 4x4, It's a HUMMER
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ThysleRoux
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#52

Post by ThysleRoux »

Neil, think about what you just said - how do the front wheels manage to turn with the rears not rotating at all when the diffs are locked without something breaking?

You are miss understanding the "handbrake trick" - it works when there are no diff locks active/available, as the applied hand brake reduces the chance of wheel spin in the wheel with the least traction ensuring that some power is sent to the one with good traction. The rear wheels still rotate, though. Poor man's limited slip diff ;)
I refuse to be POLITICALLY CORRECT to impress others - Deal with it
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#53

Post by XJ Junkie »

It’s not my fault that you don’t understand it
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grips
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#54

Post by grips »

All I can say is that I crawled up Road to Hell first gear low range with little throttle input. Only lost traction at one particular section with even lockers engaged. Little momentum and I were through.
Have owned Auto 4X4`s and still owns one, have several manual 4x4`s.
I will take a manual everyday. As Andrew said that big diesel and low first have nothing to stop it.

Only thing I love about an auto is pulling away against a dune where you can limit wheel spin by using the brake.
But then I can do the same thing with the Yank Ranger and its Centerforce clutch.

Have seen to many auto`s boil their oil in severe conditions. That happened to my 4.0l Auto Ford Ranger on a few occasions in deep sand and crawling steep inclines.

Saw an Chev Blazer and Dico spitting auto oil all over the place in Kalahari dunes with temperatures souring pass 40 deg
You will never find me without Stroh or a 4x4 :D

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Sennin
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#55

Post by Sennin »

grips wrote:
Sun Apr 28, 2019 5:34 pm
All I can say is that I crawled up Road to Hell first gear low range with little throttle input. Only lost traction at one particular section with even lockers engaged. Little momentum and I were through.
Have owned Auto 4X4`s and still owns one, have several manual 4x4`s.
I will take a manual everyday. As Andrew said that big diesel and low first have nothing to stop it.

Only thing I love about an auto is pulling away against a dune where you can limit wheel spin by using the brake.
But then I can do the same thing with the Yank Ranger and its Centerforce clutch.

Have seen to many auto`s boil their oil in severe conditions. That happened to my 4.0l Auto Ford Ranger on a few occasions in deep sand and crawling steep inclines.

Saw an Chev Blazer and Dico spitting auto oil all over the place in Kalahari dunes with temperatures souring pass 40 deg
easy solution, I just installed a 40,000BTU ATF cooler, cant get my auto gearbox temps up above 70 degrees. need to install a bypass valve for cold places like lesotho etc :roll:
It's not a car, It's not a truck, It's not just another 4x4, It's a HUMMER
HUMMER H3 Adventure 5.3V8
MAZDA BT50 3.0CRDi

Ricof4e
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#56

Post by Ricof4e »

grips wrote:
Sun Apr 28, 2019 5:34 pm
All I can say is that I crawled up Road to Hell first gear low range with little throttle input. Only lost traction at one particular section with even lockers engaged. Little momentum and I were through.
Have owned Auto 4X4`s and still owns one, have several manual 4x4`s.
I will take a manual everyday. As Andrew said that big diesel and low first have nothing to stop it.

Only thing I love about an auto is pulling away against a dune where you can limit wheel spin by using the brake.
But then I can do the same thing with the Yank Ranger and its Centerforce clutch.

Have seen to many auto`s boil their oil in severe conditions. That happened to my 4.0l Auto Ford Ranger on a few occasions in deep sand and crawling steep inclines.

Saw an Chev Blazer and Dico spitting auto oil all over the place in Kalahari dunes with temperatures souring pass 40 deg
Die autoboxes van die voertuie genoem in jou post in nou nie bekend as die beste autoboxes nie :D

Maar ek stem saam, ek van 'n manual enige tyd van die dag bo 'n auto as ek moet "off-road"
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grips
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#57

Post by grips »

They say the Chevy TH400 auto box is one of the best out there. I do not know them, I am familiar with Ford auto boxes
You will never find me without Stroh or a 4x4 :D

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