Discovery 2 TD5's offroad at Yarwell Quarry

Small video showing a steep, stepped climb and how adding traction aids can improve things significantly.

Category:

Autos & Vehicles

Tags:

• Discovery
• TD5
• Land
• Rover
• Offroad
• Yarwell
• Traction
• Control
• ARB
• locker
• 4x4

[ciarlienchi]

@roloply and Discovery2TD5..... seems that both of you don't know much abt differentials, but the rear diff lock without the CDL engaged is useless.

If the Central Diff is open and the rear is locked all the traction will be transfered to the front diff that is open too and the TC will be called to control the front wheels that will spin. There will be no traction on the rear .

1st thing is to lock the CDL in this way the torque will be splitted 50% on front and 50% on rear. follow on next comm

[Discovery2TD5]

@ciarlienchi

At which point was it mentioned about an unlocked CDL ??

I think you need to see the title and specs of the vehicle in the vid tbh before you say "we dont know much".

[ciarlienchi]

@Discovery2TD5 You're right, I missed the word "CDL" on the second attempt, so I thought you have engaged the ARB locker without the CDL. Btw my indications are not wrong. It would have been better if you made an intermediate attempt with TC and CDL locked (on 1st attempt the CDL was open and just the TC was working), and then then last attempt with all locked. Bye, Ciarli

[Discovery2TD5]

@ciarlienchi

Agreed, another attempt (which incidently has been done since with the first vehicle now fitted with a CDL as well) would have been good to show all 3 scenarios, but that needs to be done all on the same vehicle and same driver to make it a fair comparison.....the actual video was not "aimed" at seeing the differences as such, thats just how it turned out.

[ciarlienchi]

follows from previous comment:

Then if you lock the rear too you will have 25% torque on each back wheel and TC will just control the remaining 50% torque on the front axle.

But without the CDL (or the CDL opne that is the same condition) and the rear diff locked you will simply transfer the total traction to the wheel with less grip (on the front axle). you must always follow the 3 steps: central, rear , front when locking differentials. No way it works if you lock just the rear. Bye, Ciarli

[Discovery2TD5]

@ropoly It simply would not do that as both rear wheels are travelling at the same speed / rotation.

[ropoly]

@Discovery2TD5 ok .. so the abs is on and the rear diff is lock. You brake and abs comes on what happens when it's applying more brake power on one wheel and less on the other ?

[Discovery2TD5]

@ropoly No your right the TC does use the ABS system to "detect" wheel spin and then apply the brakes to the spinning wheel to transfer torque to the other wheels. When you add physical locks, the TC system cannot compare an average as the wheels are spinning at the same speed (locked together), therefore it simply does not "need" to work.

Why the ABS turns of on a mitsi is something I dont know about tbh........seems a bit weird, but ABS not needed when offroad tbh,

[ropoly]

@Discovery2TD5

I'm telling this because on my Mitsubishi when i lock the rear diff abs turns off automatically and as far as i know TC is based on ABS or i might be wrong.

[Discovery2TD5]

@ropoly

Any physical locks you add just makes the TC more redundant.