Thread: Getting 2018 D5 SD4

14,

I've had my MY18 SD5 since new. Happy to discuss my love/hate relationship with this vehicle.

Great economy.
14 weeks off the road with an unnecessary engine change. The issue turned out to be a leaking inlet manifold.
Dreadful customer service from JLR and the local dealer.
Fantastic ride and dynamics, especially on the highway.
Meridian sound system sounds great.
Can now play mp4 files en masse after 3 years of infotainment updates and a total lack of care from JLR.
Huge cargo capacity. I often use the car to do construction site deliveries and anyone unloading is always amazed what the thing will carry with the seats down.
Safety tech, while intrusive, works as advertised.
I think the D5 is better off road (on sand) than the D4's & 3 I had previously, but that could be down to less weight to haul around.
Turbo lag at intersections is annoying.

The above sounds like a whinge...which it is...but I'd buy a D300 Disco or Defender tomorrow if I could find one.

Cheers,

Mark

Fantastic car to drive. It Also tows 3000 kg caravan with ease. BUT…. The car requires a new long motor. It went into limp mode at Gundagai. No oil in motor. Further analysis revealed no pressure in cylinder one. Technician advised that the piston had shredded the cylinder wall. No explanation yet of why this occurred.

There is extensive discussion in other forums that the diesel particulate filter (DPF) regeneration process (which burns the soot out of the DPF) can cause diesel to drain to the sump diluting the oil.

It may be that the promoted service interval is too great and oil needs more frequent change. I am waiting a new motor and advice to prevent a repeat.

Here’s the thing. I know of one other D5 SD4 that has required a long motor replacement. These modern vehicles all use the JLR ingenium engine which is available in petrol and diesel formats and 3, 4 and 6 cylinders. It seems to me that the ingenium diesels are plagued with a design issue. During operation the diesel deposits particulate (soot / carbon) in the Diesel Particulate Filter (DPF). I have read elsewhere that a sensor detects the soot buildup and the car cleans the filter by directing hot gasses through it when the vehicle is working (passive regeneration); BUT short trips are a problem. The filter doesn’t clear. So what Landrover and others have done is implement a second process (active regeneration) that injects diesel into the filter which burns the soot out. I understand that Landrover uses the exhaust stroke of the piston to inject the diesel for active regen and this is where I suspect the problem may occur. Diesel injected this way is ok provided that active regen runs to completion (about 20 - 30 minutes); but if the motor is switched off during regen then diesel is left in the cylinder. This I think is bad from two perspectives. Firstly, the diesel drains into the sump diluting the oil. That’s why more regular oil changes are now recommended. Secondly, when draining into the sump the diesel washes the oil coating off the cylinder wall. On restart the piston rings are unlubricated and scour the walls of the cylinder putting micro metals into the motor. Over time these cause the motor to wear rapidly and result in the kind of failure that requires a long motor replacement.

I posted the above on an F-Pace forum in USA which raised a response about a class action. They appear to be a litagious mob in the states. Anyway, I responded in that forum with the following:

I should add that I purchased vehicle with 5 years maintenance and it has been serviced in accordance with the dealer’s service plan.

I am working on getting my theory on the design issue acknowledged firstly by JLR Australia and subsequently identification of any mitigating operating requirements, and assistance from them with implementation.

If I am correct, I imagine such things as more frequent oil changes, leaving the vehicle idling at short stops and disabling the engine start/stop function could be beneficial for motor longetivity and their may be others (eg fuel additives).

Litigation may be possible but it is extraordinarily slow here. There is also a legal requirement for a minimum 8 claimants in Australian law. I know of two. I also speak from experience having previously been involved in a successful class action against a large corporate that ran for nearly a decade.

Originally Posted by NWGG

I have read elsewhere that a sensor detects the soot buildup and the car cleans the filter by directing hot gasses through it when the vehicle is working (passive regeneration); BUT short trips are a problem. The filter doesn’t clear. So what Landrover and others have done is implement a second process (active regeneration) that injects diesel into the filter which burns the soot out. I understand that Landrover uses the exhaust stroke of the piston to inject the diesel for active regen and this is where I suspect the problem may occur.

The DPF load is both calculated by an estimated soot value in the ECU and measured by a differential pressure sensor across the DPF. The DPF loads up and requires burn-off.

All DPFs require active regeneration (burn off). That requires a significant increase in exhaust temperature and there's 2 ways to do it. The first is a downstream injector that pumps diesel into the exhaust pre-dpf. I believe some GM units do that. The other is extra diesel injection on the exhaust stroke. That's also very common among other vehicles.

So while there may be a design issue with the algorithm on those LR engines, it's a very common method of regeneration, and in fact has been used on DPF equipped Discovery diesels since the EU4 D3.

DPF equipped vehicles are just not suitable for short trip shopping trolleys.

Toyota just had a DPF class action verdict go against them.... lots of $$$ there...

Originally Posted by Pedro_The_Swift

Toyota just had a DPF class action verdict go against them.... lots of $$$ there...

Will be appealed no doubt so will drag on for a while.

I cant work out why LR dont have a burn switch which helps with the DPF issues,like quite a few other brands.

Although with the work vehicles we have, we have never had to use it,nor had any DPF issues,and some are close to 7 yrs old.

Originally Posted by scarry

Although with the work vehicles we have, we have never had to use it,nor had any DPF issues,and some are close to 7 yrs old.

I do have some regret about dropping the DPF from the D3, but its proper functioning relied on a considerable number of external sensors and systems which in a chain made it the "end of the line". Post event investigation showed what was indicated as a DPF failure (DPF full, call workshop) was actually caused by a failure of a thermocouple which prevented the system from initiating a burn off. In reality it wasn't a failed thermocouple but a wiring harness that had been rubbing on the driveshaft because the previous mechanics hadn't properly secured it after the last work they did down there (turbo replacement). So like most failures on the vehicle, it came down to crappy workmanship.

Having just suffered an EGR failure and replacement I wanted to plug those and the DPF relies on the EGR for burn off, so it had to go. It was nice however to never have any smoke, or that lovely cold-start diesel smell.

I posted on this quite a while ago.
There are two systems for DPF regeneration.
GM uses an extra injector on the DPF to squirt fuel into it to regenerate.
Land Rover just richen the mixture when regeneration required and if the regeneration does not complete the extra fuel dilutes the oil and can cause failure of the engine.

I do not know why Land Rover do not use the GM system as it seems intrinsically safer for the engine as there cannot be oil dilution.
maybe cost? maybe licence fee?
who knows?
Regards PhilipA