Maybe, dunno. And have no idea why my mate thinks this. I suppose it is still possible that shells with no tabs could still have stayed in place. But tabs on shells are soooo flipping basic why on earth change them? Except for a tiny saving in manufacturing costs.
Td5 has no tabs., many engine have no tabs.

The shells move for one simple reason, the bearing has picked up.
 
They can be entertaining in small doses. At least they don't spout false crap all the time and correct if they do say something wrong
Yet they claim they know better about the 'correct' specification of engine oil for Lion engines.... Better than the whole development departments of PSA & Ford, with their engineering qualifications, and other bits of paper that say they know their onions.... So yes, these days opinions, if on Youtube, seem to trump actual documented, tested and proven 'facts'.
 
Wonder why the s type jag and citreons dramatically have lower crank issues

Could it be down to JLR increasing the amount of BHP and torque leading to excess strain on the engines components
 
Maybe, dunno. And have no idea why my mate thinks this. I suppose it is still possible that shells with no tabs could still have stayed in place. But tabs on shells are soooo flipping basic why on earth change them? Except for a tiny saving in manufacturing costs.
It's related to how the con-rods are manufactured - they're cast and machined as a one-piece item, then fractured to enable them to have shells fitted and clamped around the crank. Machining receptacles for tabs prior to fracturing wouldn't be possible / easy to do reliably.
 
Yet they claim they know better about the 'correct' specification of engine oil for Lion engines.... Better than the whole development departments of PSA & Ford, with their engineering qualifications, and other bits of paper that say they know their onions.... So yes, these days opinions, if on Youtube, seem to trump actual documented, tested and proven 'facts'.
Fair point but he does say it's his opinion.
It's not the first time a different oil spec is 'better' than stated by the manufacturer.. eg 20/50 in the RV8
 
Yet they claim they know better about the 'correct' specification of engine oil for Lion engines.... Better than the whole development departments of PSA & Ford, with their engineering qualifications, and other bits of paper that say they know their onions.... So yes, these days opinions, if on Youtube, seem to trump actual documented, tested and proven 'facts'.
Sadly this is very true.
and academics are now beginning to anaylse it and write papers on it.
"Influencers" versus peeps who really do know about stuff.
Believing "establishment" figures is seen as being so "sheeple" that a lot fewer can bring themselves to do it anymore.
Yet sadly by not doing so they simple join another flock of "sheeple" those who believe the influencer shepherds! :rolleyes:
 
Yet they claim they know better about the 'correct' specification of engine oil for Lion engines.... Better than the whole development departments of PSA & Ford, with their engineering qualifications, and other bits of paper that say they know their onions.... So yes, these days opinions, if on Youtube, seem to trump actual documented, tested and proven 'facts'.
Don't you dare tell anyone the magic 5/40 is rubbish, it's tried and tested don't you know!
 
It's related to how the con-rods are manufactured - they're cast and machined as a one-piece item, then fractured to enable them to have shells fitted and clamped around the crank. Machining receptacles for tabs prior to fracturing wouldn't be possible / easy to do reliably.
I have done some digging and it appears the tabs were only put there to make assembly easier. But "crush" is what is used to keep them in place.

You live and learn!
 
Yes as above tabs are only for location it is the calculated crush that holds their position tabs would not help the spinning, it's the million dollar question, my bet would be on under engineering of crank for application for the torque of a discovery, but two developments I suppose you could call them were higher output pump and king bearings with a oil hole two match the feed in the block looking at them here I was surprised at the difference in size with the originals. I am guilty as charged of running 10w 40 I mulled it over then when I bought a 07 it had been run most of it life on 10w 40 ( sure he wasn't a lr time viewer) so I continued using did a 1300 mile trip to France towing huge caravan no problems quiet motor even when red hot, have only had a few but every one when I dropped the oil was like hydraulic fluid the 06 with the broken crank was worst of all
 
Not wanting to get into a protracted debate on oil specifications, all I'll say is that viscosity is only part of the specification, HA, police and other high-mileage vehicles have somehow 'survived' on the specified oil for over 350k miles. That specification was developed with many thousands of hours of test-bed development and the skills of expereienced industrial chemists & design engineers.
 
I have done some digging and it appears the tabs were only put there to make assembly easier. But "crush" is what is used to keep them in place.

You live and learn!
The disco3forum lot were going on about tabs being the be all and end all of why the 2.7 failed many years ago, not realisng that the td5 was no tabs and many many other engines, I even mentioned that the shells will not spin due to no tabs, that created ww3 I can tell you!

But I was changing a camshaft and shells on a truck engine the other day, and was surprised to see they were tabbed.
 
Absolutely all my Previous D3s were run on 10w 30 and were all high mileage, have no problem buying a higher mileage D3 or D4 last one had done 270k the one I am using now has 208k to me they are tried and tested the 06 I have broke its crank at 138k
 
Re. 10/30 vs 10/40.. it's all circumspect

You can't wait for a failure then wind the clock back and see if it will fail on a different oil

Just because a particular engine runs ok on one oil, doesn't mean it would have failed on another. It might well have run it's life perfectly well on either oil. You will never know
 
The specified viscosity is 5W30 but that doesn't take anything away from your comment - possibly the best one i've read on the subject.
 
Yet they claim they know better about the 'correct' specification of engine oil for Lion engines.... Better than the whole development departments of PSA & Ford, with their engineering qualifications, and other bits of paper that say they know their onions.... So yes, these days opinions, if on Youtube, seem to trump actual documented, tested and proven 'facts'.

Plus 1 as I’ll also stay with the 5 /30 because as u say with the extensive testing that JLR have done

Wondered if he also went over to the 5/40 because he has a DPF fitted

Apologises if you’ve already seen this regarding the 19.5 oil pump, heard some reports saying it wasn’t built very well, does translate to English ok

 
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Found the report again of a guy getting a full engineering report on his failed D4 engine

Alas above my pay grade and know u guys have a lot more mechanical engineering knowledge than myself



Question 1: "Is there a fault in the car LAND ROVER DISCOVERY 4,".

Vehicle LAND ROVER DISCOVERY 4, to be in inoperable state due to engine failure. The
following defects are revealed:

- presence in oil of small metal inclusions formed by the process of mechanical friction;
- teaser and discolourations on and crankpins of the crankshaft, the crankshaft traces overheating
(buccal) in the region of the cylinder 2 and 5;
- welding by friction liner rod of the second cylinder.

- all indigenous damaged liners, the worn out portion of the internal and external, which is
adjacent to the block and closures of wear and scuffing does not except the liner third crank journal.
Insert a third crank journal (which is attached to the cylinder block) has a strong wear of the inner
surface and the part where the locking is completely split off. There is a deformation (flattening) radical
loose leaves in consequence of shock loads.

Question 2: "What is the cause of a fault in the car LAND ROVER DISCOVERY 4,

The short length of the crankshaft, and consequently narrow and crankpins result in high loads
on the liners. Narrow cheeks of the crankshaft through which pass yet drilling the oil supply lead to
high torsional loads on the crankshaft during operation and the stress concentration at the narrowest
section.

As a result of the engine, in consequence of the action on it of high torsional oscillations
perenagruzhaet radical loose, causing them to rotate. In the test engine was a displacement of the
insert with its indigenous partial destruction (split off the part where the liner disposed locking). The
displacement in turn led to the partial overlapping of oil supplying to the channel crankpin second
cylinder. overlap oil supplying channel result was a drop in oil pressure, and as a consequence of oil
starvation rod liner
 
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