Centre diff lock

[bainswor]

Hi I own a 1977 rangie, I was wondering if there is any simple way to work out if my centre diff lock engages when I lift that button. The big red light comes on, but I dont know if it is locking.

Cheers guys.

Regards Barnaby

[ISUZUROVER]

Jack a front wheel off the ground on a trolley jack and try to drive very slowly and carefully. If the CDL isn't working only that wheel will turn.

[bainswor]

ah sounds to easy!

Cheers for that!!

Regards Barnaby

[Nick (in the Falklands!)]

...with those vacuum switches, & plastic pipe, leaks in old systems are'nt uncommon.....you can drive the difflock actuator with a footpump plugged
onto either hose once detached from the switch..

If the indicator light does'nt work (or stays on after use) it can be a gummed-up switch button on the gearbox...they clean up OK...& you can check with a screwdriver tip if the actuator is doing its sttuff through the
hole....

[daddylonglegs]

The centre difflock light switch operates directly off the difflock selector fork, so if the light comes on when you pull the switch and goes off when you push it down then the difflock must be working.
Bill.

[Ralf the RR]

I asked this question on the Aust RR and Disco forum a while back because the light was not coming on.

Jack a front wheel up.
With the diff lock disengaged, the wheel should turn.
Engage the diff lock, and it won't.

Another response was to jack the whole axle up (both wheels) and perform the same test as above.
Withe the diff lock disengaged, both wheels turn (in different directions., and engaged the wheels cannot be turned.

[bainswor]

ah ok! I jacked it up and it spun with no diff lock engaged, and then when it was engaged it tried to drive me off my axle stand.

The light sometimes stays on after I have disengaged the lock, but turns off once I have driven a little way.

The reason I thought it was not working was that I saw a video,, of me in the mud and the back wheel was spinning alot faster than what the front appeared to be.


Thanks for all the helpful input.

Regards Barnaby

Does anyone know if it is alright to change from low to high whilst moving? As the manual says it is, but I am unsure??

[daddylonglegs]

The reason your rear wheel was spinning much faster than the front is that when a vehicle without difflocks loses traction at one wheel, that can wheel can spin up to twice the speed it would if the diff were locked, so I would suggest that on the video, both your front wheels were spinning, but only one back wheel was turning. Nothing to worry about, this is normal.
Although Rover give directions in the drivers manual on changing from low to high on the move when towing heavy trailers etc, I personally have failed to perfect the technique on the Rangey 4 speed LT95 transmission.
The old series landrover t/cases, no problem. LT 230, Not bad either.
Bill.

[Ralf the RR]

ah ok! I jacked it up and it spun with no diff lock engaged, and then when it was engaged it tried to drive me off my axle stand.

Sorry.
Should have been more specific.
Turn the wheel by hand!

[Nick (in the Falklands!)]

........Bill, I was interested in what you said about Lo-Hi shifting with
LT -95 gearboxes...

I've never seen an owners manual for the Rangies to know what the
Rover Co. technique/advice was, but I wonder if its not actually more to do with individual gearboxes.......??

My reason for wondering this is because having 3 of them in running vehicles (2 x V8 101"s & a Perkins 236 engined 109" Hi-Cap), they are
all different in transfer characteristics.

The scruffy 101" will up-shift from low to high at low speed provided that the main box is knocked into neutral first...anything fast & teeth grind, but the gears themselves otherwise shift smoothly & it has an excellent main box.
The good 101" (which has a 3-speed (2,3 & 4)main box ever since I got it.....it does have a 'bottom' first gear;.....its in the bottom of the gearbox
...or at least the teeth are..the rest of it is just a bush on the shaft.. )
...this will shift up at any speed as we have always used low box 2nd as a
'first' gear....but again, main box has to be in neutral, so two-hand shifts are sometimes needed....but this T-box tolerates shifts down as well from
Hi to Lo...with the main box engaged...has to be slow moving, with large bootful of right foot to synchronize shaft speeds with double de-clutch..

The Perkins will accept Lo-Hi shifts in 1st & 2nd, but 3rd & 4th only in neutral.....& heaven help us if we try to go the other way without stopping first...!! Yet its a superbly smooth box otherwise.....

How they are different must just be a matter of minor tolerances etc, I've no other clues..!

Anyone else..?

[Thonger]

All our 110's I've driven I've been able to shift from low too high on the move, but as you said it's reving in 4L then g/box to neatrual double clutch to H then slot it to 2nd, always worked for me. Maybe it's just all our gearboxes are clapped out

[daddylonglegs]

Hi Nick, Yes the operators manual does suggest the method you describe.
ie, put main box in neutral, shift transfer from low to neutral, engage clutch, pause, disengage clutch, shift to high range, select desired gear in main box and engage clutch. I have rarely been able to make a smooth grate free change, and when trying to get and keep heavy trailers rolling, by the time I have completed the above procedure, a lot of momentum is lost, and instead of the original desired gear being say 3rd, I would have to go to 2nd or even 1st.
I perfected the high to low and back again years ago when I towed a 2 ton caravan around Australia with a 4 cyl 2A. I used to try to avoid using 2nd gear as much as possible because that is the gear that fatigues the layshaft. The series transmission do not require shifting the main box to neutral while range changing.
it may be that that the difference between high and low on a series 2At/case is only about 2:1, whereas with the LT95 it can be in some instances, depending on the model, over 3:1. Or it may be lack of familiarity on my part. Athough I have worked on and driven many Landeys and Rangeys with the Lt95, I have never actually owned one.
Bill.

[DionM]

The reason I thought it was not working was that I saw a video,, of me in the mud and the back wheel was spinning alot faster than what the front appeared to be.

Don't forget the open diffs front and rear. You can lock them front to back, but that doesn't stop a wheel on the axle spinning uselessly.

[Rainbow Warrior]

If the light comes on it's engaged basically, the light runs off the engagement fork, I did have the vacumn actuator die and managed to pry it open with a screw driver and silastic the perished rubber bellows. It worked fine for the next 12 months till I sold it.