Thread: Why do 2.7 cranks break?

Originally Posted by RANDLOVER

Well to sum up he posits the theory of the the wrong class of 5W-40 oil, and says the engine was designed before the new low viscosity class was invented and they later recommended the new class oil for the engine, so old ACAE C3 vs the new ACEA B5/A5.

Definitely plausible as he states only LR went this way on the oil spec and not other PSA engine users hence the concentration in LR. The oil choice (thin) is for reduced spinning friction fuel efficiency and not longevity.

I’ve been waiting and hoping the oil gurus would take on this hypothesis. Ivan in the video seems to know a thing or two about oil.

And here’s me slavishly following the recommended oil spec. Think I’ll change to 20W-50 Dino from now on

What is interesting is what Penrite comes up with for the different versions of the 2.7.

Land Rover D3/4: A3/B4
Citroen C5: C3
Peugeot 407: C3
Jaguar XF: C1
Ford Territory: A5/B5

Should note that Citroen, Peugeot and Jaguar would have DPF’s hence the C spec oil. It appears only the Jag and Territory was bringing up the lower HT/HS viscosity oils (C1 and A5/B5) compared to the A3/B3, A3/B4, or C3 oils.

Was it being suggested we should (or shouldn’t) use the lower HT/HS viscosity oil? Awaiting to hear comments from an oil guru.

Oval Autos in the UK does a lot of TDV6 engine rebuilds and change outs and their observation was 9/10 times the failure was accompanied by injector issues.

Another person who works for another repairer in the UK made the same observation believing injector issues lead to fuel contaminating the oil and this results in the bearing failure that can then lead to a snapped crank.

DISCO3.CO.UK - View topic - Range Rover 3.6 TDV8 - anyone got a head gasket?

Interestingly a recent 3.0 failure reported on this forum also noted that the car had been misfiring for a few weeks before the crank snapped.

In the LR Time video, it was noted that Fabian could actually hear something had change prior to his failure. In his case, he detected the spun bearing before major damage had been done.

With a marginal crank and bearing design, it is plausible that a leaking injector could contaminate the oil and lead to a failure in a relatively short time - with the risk increasing if the oil change interval is extended - and LR probably push this envelope further than most.

No doubt there are many contributing factors, but what is clear is if you have a misfire or hear something that sounds different - stop and investigate.

Ok, think about this. LR injectors are just Bosch etc injectors used in millions of engines that aren’t breaking cranks. I’m also pretty confident that the other permutations of this engine would also use the same injectors and they’re not snapping cranks. So the idea that only in an LR an injector issue leads to a snapped crank, but not in anything else seems a stretch.

Injectors are also pretty reliable and thus it doesn’t explain the low Km, in some cases pre-first service vehicles that have failed cranks.

LR service intervals aren’t much different than many cars on the market these days. Yes they’re long but again, many cars with increased servicing have failed as well.

Remember we are primarily discussing the 2.7 failures not 3.0 and these failures tend not to be early in the life. Most 2.7 failures happen after 160-200K. Injector problems after 200K is not uncommon.

The 2.7 also uses different injectors to the 3.0 and the suggestion is that fuel contaminating the oil is enough for the poor bearing design and poor crank design to tip it over the edge. Same as using the wrong oil can lead to failure.

Interesting that two repairers in the UK (and one of them probably does a large portion of the work) made the same comment that they see injector issues accompanying engine failures.

No doubt there are many contributing factors - only have to look at the size of the crank to see it is a poor design. The size of the counterweights look much larger which would add to the flexing of the shaft, the webs look small, there is a known undercut issue, even the harmonic balancer looks under sized.

Add to this not using locating tabs on the bearing shells and you have all the elements that can lead to a failure for the unlucky few.

The 3.0 seems to be different again when it comes to failures, but the crank and bearing design is a common weakness. The extended oil changes and if using the wrong oil could be contributors as well.

The crank design is at the centre of all of this, the question then is how best to minimise the likelihood of having a rare failure.

Originally Posted by DiscoDB

What is interesting is what Penrite comes up with for the different versions of the 2.7.

Land Rover D3/4: A3/B4
Citroen C5: C3
Peugeot 407: C3
Jaguar XF: C1
Ford Territory: A5/B5

Should note that Citroen, Peugeot and Jaguar would have DPF’s hence the C spec oil. It appears only the Jag and Territory was bringing up the lower HT/HS viscosity oils (C1 and A5/B5) compared to the A3/B3, A3/B4, or C3 oils.

Was it being suggested we should (or shouldn’t) use the lower HT/HS viscosity oil? Awaiting to hear comments from an oil guru.

So it is the 3.0 that LR change oil spec to the low HT/HS viscosity oil - namely C1 like Jaguar. Whereas Citroen stuck with C3 for the 3.0.

Makes me think there is more to this oil spec theory.

penrite oil recommendation for the ford 2.7l tdci

ford 2.7 oil.jpg

penrite oil recommendation for the landrover 2.7l tdv6

lr 2.7 oil.jpg


both meet fords wss-m2913-b spec which is the original ford spec in 2012 but their oil specs website states that these days wss-m2913-d should be used where -b was originally recommended

penrite oil recommended -d oil

c3 2.7 oil.jpg

which is what my old vw 1.9l diesel caddy used and is the slipperiest oil i ever got on my hands over the years

oils aint oils it seems

is confusing as hell

Originally Posted by DiscoJeffster

Ok, think about this. LR injectors are just Bosch etc injectors used in millions of engines that aren’t breaking cranks. I’m also pretty confident that the other permutations of this engine would also use the same injectors and they’re not snapping cranks. So the idea that only in an LR an injector issue leads to a snapped crank, but not in anything else seems a stretch.

Injectors are also pretty reliable and thus it doesn’t explain the low Km, in some cases pre-first service vehicles that have failed cranks.

LR service intervals aren’t much different than many cars on the market these days. Yes they’re long but again, many cars with increased servicing have failed as well.

I also don’t believe an injector could fail bad enough to dilute oil and not give a code or fault. You’d see elevated oil levels also with enough diesel to contaminate it.