Hey guys, new to Discos here so forgive me if this question has been explained ad nauseum.

The Disco I series all come with CDLs, correct? Unlike the Disco II where only the 2004 series had them. How does the CDL on the Disco I work? Is it just a lever one pulls to lock the diff? Are there any advantages to installing a third-party locker (like an ARB or something.)

Also, what kind of suspension does the Disco I have? Is it independent or one solid axle?

Thanks!

 

Yes. They all have it. It's controlled with the transfer case shifter, just move it to the left to lock it. All this does is lock the two drive shafts to spin together. At this point it behaves just like a regular 4wd, when in 4wd. It has nothing to do with the axles... so all of the normal stories apply to adding an ARB or detriot or whatever. The only thing is you don't want a detroit on the front of a rover regularly driven on the road.

Solid, full floating axles front and rear, with coil springs.

 

Yeah I have no idea why I wrote axles when discussing the CDL. But it sounds like the Disco has axles similar to, say, a Jeep Cherokee?

What are the normal stories about adding a third party locker?

 

Probably a little stronger than SOME of the Cherokees, but hard to say because they have so many different axles over the years. The suspension is a little better on the disco, than the Cherokee... the Cherokee has leaf springs in the back and some wimpy looking control arms in the front.

The normal stories are... more traction. You have open diffs front and rear and if you want to have all four tires powered you'll need lockers or something like them. You'll be amazed at how far you get without them though. My D1 would go all kinds of crazy places, probably because of how much articulation the stock suspension has. If the tires are always on something solid, lockers aren't needed as MUCH as when, say, a tire is in the air.

Though part of why my D1 was so good off road, for a stock vehicle was that it only cost me $1200 and so I wasn't scared to break something.

 

Depending on the year/model Cherokee it has a solid axle in the rear and independent suspension in the front with coil springs in the front and leaf springs in the rear.
All DI's have solid axles front and rear with coil springs on all four corners.
DO NOT drive on dry paved roads with the center locking differential locked, you will destroy it.
Normal driving the LR is a full time 4x4.
As for a locker, if all you are doing is camping and 2 tracks or the like a locker is not needed.
Unless you are rock crawling or mudbogging all you need is skill, a Hi-Lift and a recovery strap.
Watch this video, best advice is to test your truck before you spend money on modifications that you probably do not need.
Get it in good running order before spending money on offroad gear.

Trail Issue 4x4 Land Rover Stock Off Road Test

 

Yeah, I was talking "Cherokee" not "Grand Cherokee" All of the little ones should be solid axle front and rear.

 

Maybe I'm misunderstanding something.

Under normal driving condition, the differential is open, and the wheels can turn at different rates. But if one locks the CDL, doesn't that cause the wheels on the left and right side to turn at the same rate? Or does the CDL do something different?

 

No, your differentials are 'open' regardless CDL status. Open differentials (front/rear axles) will only send power to the wheel (L/R) that is turning. An 'All Wheel Drive' vehicle driven on dry pavement must have a provision for slippage between the front and rear axles. With the CDL unlocked the front and rear differentials can turn at slightly different speeds such as during cornering, etc. I'm not completely sure how it does this...either with clutches or fluid pressure I'm thinking. Once the CDL is engaged the front and rear differentials now are 'locked' together and must turn at the same speed like any standard 4X4 truck or jeep with a transfer case.

As far as 'locking' the left and right on the same axle, you need a locker or limited slip to ensure they both get power in situations like one wheel/tire in mud/ice or a wheel/tire is in the air. Hopefully that answers your question...

 

Somewhat...

So the CDL control only the rates of turn on the front/rear axles and not the left/right wheels? So its not really a locker then, which is what I was under the impression it was.

So then, what are the advantages of the CDL then?

 

Unlike most other four-wheel-drive vehicles, all
Land Rover products have permanent
four-wheel drive.
Discovery is enhanced by the inclusion of a
lockable differential (diff lock) between
the front and rear drive shafts. With the
differential locked, the drive shafts to front and
rear axles are, in effect, joined together, causing
both to rotate at the same speed.
This feature enhances traction on difficult
off-road surfaces. However, with the differential
unlocked, the different running requirements of
the two axles can be accommodated, thereby
enabling Discovery to operate permanently in
four-wheel drive for both normal AND off-road

use.

When to use the diff lock
As a general rule, the differential should be
locked only in order to drive on loose or
slippery off-road surfaces. ALWAYS unlock the
differential for normal road driving or as soon
as a surface giving good grip is reached

whether high or low gears are selected