D3/4 driveline strength

[Slunnie]

Hi folks,

Has anybody heard much about driveline failures in the D3/4/RRS? I had never heard anything about it until recently where a D4 broke a CV. Just wondering if this was freak or if the incidence of failure will increase with harder use and age.

[Jamo]

Not really Slunnie!

I have heard of some snapped CV joints in D3's, but these were when in extended mode at full lock. I daresay there would be increased risk with those vehicles that run shortened height sensor rods. But i's definitely not a common thing.

There is (I believe) a mob in the UK who are (have?) developing a tougher CV joint.

[Graeme]

..in extended mode at full lock.
I cringe at the thought of applying much power at all on full lock with such a tight turning circle.

[stig0000]

no "brakes" as such,,, just clunking cv's, wineing diffs;) stuff like that

[DiscoSaffa]

but these were when in extended mode at full lock.


I cringe at the thought of applying much power at all on full lock with such a tight turning circle.

This used to be a big problem in the early days of "Hot Hatchs". Turbo charged 4cylinder motors developing 200+kW…… didn’t cost much money……. And as a result 200kW in the hands of 18 year old plonker……. Pulls up at a traffic light turning left……. Wheels to full lock and dump the clutch……. Snapped CV…….

The amount of power, and for more importantly in this discussion, torque that is going through those front CVs on a D3/4, at full lock, with the added strain of extended mode, and the inertia of a 3 ton vehicle, scares the hell out of me……. I tend to be careful with the power application (and I only have a V6) and try to avoid planting the right foot in anything but a straight line…. :burnrubber: I am probably over cautious, but the point I am trying to make in a roundabout way, is that one needs to understand one’s vehicle, the mechanical limitations (not necessarily unique to a specific vehicle), and drive accordingly……

Just my 2 cents…….

[Tombie]

No engineering solution can make up for common sense :cool:

[DiscoSaffa]

No engineering solution can make up for common sense :cool:

X2!!

I am sure you get them here too, but there is a special kind of 4x4er we get in South Africa...... you will all be standing around an insurmountable obstacle, pondering options…… a tricked out cruiser will pull up, a large gentleman steps out and says to the closest person “heer, hou my dop, nou wys ek jou ‘n ding” which loosely translated means, “here, hold my drink (brandy and coke more often than not), let me show you something”……. Said person sets off…. Net result is a broken cruiser, a smashed ego, and a few grinning Land Rover drivers……. Oh, and the obstacle is still insurmountable………

[trobbo]

I wonder if transmissions will become a more common failure as these vehicles get older.
Transmissions are being replaced on vehicles used for towing.
Towing will result in higher atf temps which may be replicated with extended off road use.
As these vehicles become cheaper they will be used more off road, the maintenance will drop, that $100 a litre atf fluid wont get replaced and transmissions will go bang.

[Tusker]

G'day Slunnie

Not a breakage as such but Herve's D3 once snagged a CV boot at Jenolan. If that wasn't picked up it would no doubt lead to premature failure.

Regards
Max P

[rmp]

Interestingly, the D3, the car that can tell you if so much as a brake light sensor malfunctions for a nanonsecond, has no way to let the driver know a CV joint is snapped. You may think the driver would notice, and of course you know something's wrong, but not what.

A tip, if you need to drive out with a broken CV use Rock Crawl as that prelocks the centre diff which is what you'll need to do to avoid all the drive going to the broken CV. Other modes work but RC is best. It's perhaps the only time I've wished I could lock a D3's centre diff manually.

[Slunnie]

Interestingly, the D3, the car that can tell you if so much as a brake light sensor malfunctions for a nanonsecond, has no way to let the driver know a CV joint is snapped. You may think the driver would notice, and of course you know something's wrong, but not what.

A tip, if you need to drive out with a broken CV use Rock Crawl as that prelocks the centre diff which is what you'll need to do to avoid all the drive going to the broken CV. Other modes work but RC is best. It's perhaps the only time I've wished I could lock a D3's centre diff manually.
Rob I was under the impression that the centre diff wouldn't lock if a CV was broken - just to clarify, you're saying the CDL can be locked still and you can still have drive?

[rmp]

Yes. The car has no idea a CV is broken, as I'm sure if it did there'd be about 2000 warnings shown. Therefore, as far as it's concerned the front right wheel say is just very easy indeed to turn, like it's in the air. Differential theory tells us that's where all the torque would go, unless something stops it. In the case of the D3 the centre diff locks and at the front the ETC works as best it can to equalise the torque, which it's never going to be able to do. Rock Crawl helps as it preloads things more. The car (not mine, I would like to clarify) was able to drive out but not up an incline till it was put into RC. If the CDL hadn't locked we would not have been able to move the car.

In the same way if you break a CV on a car with ETC pull the ETC/ABS fuse to disable the system so the ETC doesn't work on the front axle.

[gghaggis]

Yes, you can use Rock Crawl if you break a CV. BUT ..... if you break a front CV joint (who, me?:angel:), you'll have great difficulty negotiating corners - the drive will disengage the centre diff and you coast to a halt. So the the technique required is to build up the momentum you need prior to negotiating the corner.

I had the locking rear eDiff, and it was still a pretty hairy trip home! Hills are also a drama, due to the 'hill' mode the transmission uses.

In my experience (and opinion), the D3/D4 has one of the strongest drive trains ever put into a production Landie. I've bashed the hell out of it, things that continually broke my heavily modified D1, the D3 just shrugs off!

Cheers,

Gordon