Rear diff lock

[Compressor.guy]

So, I have the HD package and the rear diff lock shows on the screen when I go into rock crawl mode, but when I look in the configuration on the IID tool it shows electronic rear diff is not enabled. What's up with that? Should I change the configuration or leave it alone since the diff is showing on my screen?

Thanks,
Jeff

 

[umbertob]

What menu / submenu of the IIDTool did you get that information from? IIDTool Main Menu > Car Config > (Press + to load the CCF) > IPC - Instrument Pack > Scroll down to Locking Rear Axle Diff. Should say "Fitted". If it says it's fitted, you are good to go, don't change any settings. "Not enabled" might be a live value or I/O value you are getting from a different IIDTool menu, not enabled meaning the rear lockers are not locked at that particular time - padlock on the touchscreen is green as in your photo. When the rear padlock turns rad (rear diff is locked, this happens automatically when off-roading in low range, you can't control it manually), IIDTool would probably display "Enabled".

 

[Compressor.guy]

Thanks Uberto. I checked again and I stated incorrectly when I used the word enabled - it actually says "not fitted".

I am sad now, because I crawled underneath and I see no signs of having the locking diff. I really wanted this feature when I bought the car and looked at a number of them. I incorrectly learned that if the display showed the rear lock symbol then the car was equipped with the rear locker. This seemed to make sense because most of the LR4's that I looked at did not show the symbol for the rear diff, but this one did (and one other). All of the ones I looked at were in the 2010-2012 year range. I don't understand why some would show the lock symbol for the rear and some not if they don't actually have the rear locker fitted? Oh well, too late now, I already purchased the car and not worth trying to trade it at this point. I just got my Comp 18" rims with BFG's installed so I'm ready to hit the trail and see how it does.

Thanks,
Jeff

 

[umbertob]

Ah, bummer. Yeah, the graphics on the 4x4 screen were a bit confusing up to MY2011, where it shows a lock on the rear axle even on vehicles fitted with an open rear diff, so the icon simply stays green all the time. Graphics were changed on MY2012+ to display the rear axle padlock only on cars fitted with rear lockers - and there is even a small gauge around the icon that shows how "locked" the diff is - since it is a variable ratio on this electronic unit. Pretty neat, and much clearer than earlier model years, but ultimately a bit useless. You won't be staring at the touchscreen while your diff is turning off and on, trust me.

Oh well, don't worry. The car is plenty capable without rear lockers, as many owners here who wheel regularly without HD pack can surely tell you. You have the basic bits you really need: A sweet and torquey V8 engine, EAS for ground clearance, a low range, and a terrific traction control system with point-and-shoot programs (Terrain Response.) Your 18" wheels and aggressive A/T tires will make a much bigger difference than a locking rear diff in most off-road situations. Congrats, and post some photos!

 

[PaulLR3]

As umbertob noted, these vehicles are very capable without the rear locker. We have one LR4 with a rear locker that we ordered new and a used one without it. (It was nearly impossible to find a used 2013 HSE-LUX with a locker) Both do just fine in deep sand on a nearby drive-on beach and in deep snow in winter. I think the rear locker comes into play when one of the rear wheels is off the ground.

Last year at a Land Rover off road event held at a sand and gravel pit, vehicles without a rear locker (Evoques, Range Rover Sports and LR4's) made it through a crazy obstacle course without any problems. The vehicles that got stuck were older models, including a Defender. One instructor explained that the newer electronic traction control systems are superior to older mechanical systems.

 

[TLB]

Rear locking diff. problem

Hi everyone.
I did not want to create another thread, so I am posting this here.
I have noticed a screeching / squeaking / chirping noise when shutting off my LR4. ( it is also present when you turn ignition off from accessory mode- engine not running). The noise originates from underneath the car.
Since I dropped the truck for service anyway, I asked my service advisor to look into it.
Well, ... I received a call today and was told that this sounds was coming from my rear locking differential. It has to be taken apart to see what is going on.
The truck is still under warranty so it should be covered.
This is 2013 LR4 Lux with HD package , about 33,000 miles. I do take it off roading quite a bit, so my rear locker is put to work regularly.
I did quick search and found a post where LR3 owner had similar symptoms and had to replace rear lockers motor/ solenoid.
Did anyone encounter something similar? What could be the cause of this?

 

[PaulLR3]

That LR3 owner was probably me. I had the exact chirping noise you are describing when turning off the ignition. I was told that catching this issue early is key. If not replaced, the solenoid can lock up permanently which will damage the entire rear differential. I think the repair only took a couple of hours.

Just one more issue that carried over from the LR3 to the LR4.

 

[TLB]

Thanks PaulLR3. Just got a call from a dealership
Rear locker motor was replaced.
Any idea why the motor would fail?
What is a chance of this to happen again. I am under warranty but once out of warranty it will be different $$$.

 

[umbertob]

It's an electric motor, so... I guess it can fail. FWIW, I am on my second Land Rover with this electronic locking rear diff. Both the first one (2006 Sport sold with 208K miles) and the current (2013 LR4 with 106K, and counting) never gave me any trouble. I replace the extremely expensive LRD fluid every 75K miles, that's all. No whining, no chirping, no problems. Hopefully I didn't just jinx myself.

 

[TLB]

Hi Umberto,
Glad to hear from you since my set up and off road usage of the truck is similar to yours. Except amount of higway driving. ( in the past my wife was doing +40 ,000 miles per year an at the same time I was doing about 23,000 per year and this when gas was almost $4.
I hope this new motor will last.
If you hear your LR4 chirping when shutting off at least now we know what causes it and what to do.
I am happy they fixed it so I still can hit the trails on Saturday and put my rear locker to work.