4 wheel drive ??

[tezzer]

a pal of mine has a disco, we were having a discussion about 4 wheel drives, could anyone clear up a quiery, if for instance we were to chain his disco to a tree in a muddy field, 1- how many wheels will be turning in nornal drive, -2 then select centre diff lock how many wheels turn then,


i thought that disco's drove one front and one rear in normal drive with bias to rear wheels say 70-30 or 60-40 , and with centre diff lockin 50-50, he seems to think with centre diff lock all 4 wheels will turn?, i thought that only happened if axle diff locks were fitted






tezzer

[zippy656]

Originally Posted by tezzer

a pal of mine has a disco, we were having a discussion about 4 wheel drives, could anyone clear up a quiery, if for instance we were to chain his disco to a tree in a muddy field, 1- how many wheels will be turning in nornal drive, -2 then select centre diff lock how many wheels turn then,

i thought that disco's drove one front and one rear in normal drive with bias to rear wheels say 70-30 or 60-40 , and with centre diff lockin 50-50, he seems to think with centre diff lock all 4 wheels will turn?, i thought that only happened if axle diff locks were fitted

tezzer

im suprised youve not got him to change yet Tezzer...

i though the disco was always 4wd, so only the slipping one would trun, then with the dif lock all four would turn.

a T2, both back wheels would trun, then in 4wd low all ours would turn.

thats what i think, but like to know if im right?!?

[tezzer]

hi zippy, he wont change, he winds me up about my truck he calls it "GAY MOBILE" so i sent him some of the pics off this site last night showing that nissans & mavs go where disco's go, im still waiting for a reply.









tezzer

[daveg]

hi tezzer

I thought the disco was permanent 4wd and when diff on, it changed locking diff. I have had a disco in past, but recall. it was always breaking down, so got rid of it. then went to toyota, what a joy and now nissan and no problems with them either...so far...

dave g

[Deleted Member S]

Hi Tezzer a disco is perm 4WD but IIRC can easily go to 2WD (1 rear & 1 front wheel) as they are open diffs (no LSD or locker) unlike a T2 which can go down to 3WD (both rears & 1 front as the front diff is open)

[tezzer]

hi sweety, so if we chained his disco to a tree in a muddy field, and i drove it in normal range, how many wheels will turn??









tezzer

[Terranosaurus]

Thought someone would have got it right by now.

Disco is fulltime 4wd (most but not all have selectable centre diff lock)

Disco in normal mode - 1 wheel will spin.
Disco with diff lock - 1 front and 1 rear wheel will spin.
Disco II TD5 with traction control - will stop and start each wheel trying to get traction using the brakes, but probably wouldn't even pull the chain tight.

T2 in 2wd - both rear wheels will spin
T2 in 4H or 4L - both rears and one front.



This is why ARB sell locking diffs for landrover axles

[tezzer]

Originally Posted by Terranosaurus

Thought someone would have got it right by now.

Disco is fulltime 4wd (most but not all have selectable centre diff lock)

Disco in normal mode - 1 wheel will spin.
Disco with diff lock - 1 front and 1 rear wheel will spin.
Disco II TD5 with traction control - will stop and start each wheel trying to get traction using the brakes, but probably wouldn't even pull the chain tight.

T2 in 2wd - both rear wheels will spin
T2 in 4H or 4L - both rears and one front.



This is why ARB sell locking diffs for landrover axles

hi Terranosaurus, ok but he has phoned me today while out fishing he tried it, in normal drive (his son was watching) both front wheels spun and no rears? which seemed strange to me, i always thought disco's had one front and one rear wheel driving with a bias towards the rear and when centre diff was engaged both axles drove at 50/50 so wheels pushed and pulled together if get my drift.






tezzer

[Timbo_1975]

It would come as no surprise then, that his Disco is f*cked!

Tim

[Thomas-the-Terrano2]

would leave it chained to tree, mind who would nick it?

[Terranosaurus]

Originally Posted by tezzer

hi Terranosaurus, ok but he has phoned me today while out fishing he tried it, in normal drive (his son was watching) both front wheels spun and no rears? which seemed strange to me, i always thought disco's had one front and one rear wheel driving with a bias towards the rear and when centre diff was engaged both axles drove at 50/50 so wheels pushed and pulled together if get my drift.

In normal mode there is a 50/50 split but only because an open diff gives a 50/50 split not because of anything special like say the ford xr4x4 or cosworth set up that gives 33/66 F/R through the use of a viscous coupling, though some rangies have viscous I beleive and some disco IIs but they're just 50/50 ones.

On either axle of a LR or the front of a T2 if the difference in resistance/grip of two wheels on the same axle is similar enough they may both spin, it depends if one breaks traction before another, if both go at once and then they are both equally free to move they will both spin. When 1 wheel spins with a open differential (and the other is stationary) it spins at twice the rotational speed it would have otherwise, so its a play off between accelerating the wheel and the other having close enough the same amount of grip.


Bottom line is though if you cross axle a disco you'll get stuck, if you cross axle a T2 the rear LSD will allow you to continueing driving - see piccy of sweety on daes trip with rear wheel 18" above the ground.

[(RIP) PLANK]

you realy need to get back tot he work of your favourite and mine Albert Einstein E=MC2 and all that, simply put:


it depends how big the tree is

[Thomas-the-Terrano2]

ref viscous diffs from solihull.

the very early classics had them before the manual locking centre diff was introduced,

the series 2 discos have regular centre diffs but with out the lock option, the lock up is
effected by the traction control linked to the abs. having seen cameramans series 2
the transfer is standard but the option to lock manually is blocked off. seems there are
kits available to retro the feature when the electricary fails.

why does the spinning wheel rotate twice as fast, isnt the output to the shafts defined
by the speed of the prop?

[iandouglas]

HI FOLLOWED DINKY ON XMAS RUN GOT TO A HILLSIDE WITH LOOSE ROCKS DINKY SAILED UP ,MY DISCO 3OOTDI SAILED THEN SUNK
TWO FLAT ROCKS "WET" AS SOON AS I HIT THEM IT WAS ALL OVER .
I WAS IN 2ND LOW WITH CENTRE DIFF LOCKED ,HAD TO TAKE REAL FAST RUN AT IT AND BOUNCE TIGGER STYLE ALL THE WAY TO THE TOP.
TALKED TO TWO DIFF LOCK LADS IN DISCOS 200TDI ,THEY GOT UP NO PROBLEM ,BUT THEY USED 4TH LOW CENTRE DIFF LOCKED .
RELIED ON ENGINE TORQUE TO PREVENT WHEELS SLIPPING.
NOW THINKING OF AN ARB OR DETROIT REAR DIFF LOCK
THE OFF ROAD GUYS JUST WELD THE REAR DIFF UP.
rgds.iandouglas

[Thomas-the-Terrano2]

Originally Posted by iandouglas

HI FOLLOWED DINKY ON XMAS RUN GOT TO A HILLSIDE WITH LOOSE ROCKS DINKY SAILED UP ,MY DISCO 3OOTDI SAILED THEN SUNK
TWO FLAT ROCKS "WET" AS SOON AS I HIT THEM IT WAS ALL OVER .
I WAS IN 2ND LOW WITH CENTRE DIFF LOCKED ,HAD TO TAKE REAL FAST RUN AT IT AND BOUNCE TIGGER STYLE ALL THE WAY TO THE TOP.
TALKED TO TWO DIFF LOCK LADS IN DISCOS 200TDI ,THEY GOT UP NO PROBLEM ,BUT THEY USED 4TH LOW CENTRE DIFF LOCKED .
RELIED ON ENGINE TORQUE TO PREVENT WHEELS SLIPPING.
NOW THINKING OF AN ARB OR DETROIT REAR DIFF LOCK
THE OFF ROAD GUYS JUST WELD THE REAR DIFF UP.
rgds.iandouglas

hmmm Ian, or could just trade disco for t2, again, or reinstate old un!