Thread: LR4 Crankshaft Failure?

Originally Posted by 101RRS

FFS then why not type D4 as we are in Aust not the US and LR4s do not have diesels.

Just to stir the pot a bit more, maybe he should have written JLRD4, or is it JLR-D4, or JLR D4?

Confused!

Apparently, and I speak under correction, a change to the crank was made at some stage for 2.7 to 3.0l, the only way to tell is the bolt for the crank pulley is larger.

Best advice seems to be service at or before 10000km intervals, dont stray from the spec'd oil and use a quality oil. Watch for leaking front main seals, a strong indicator that the crank thrust washers are worn and the end float of the crank is out of spec.

But basically we're all playing "crank roulette" with these cars.

Broken crankshafts - look at the harmonic balancer - wayyyyyy too small for a diesel with this much torque. Lr are relying on timing belt to remove harmonics.
3rd and 4th order harmonics can destroy any steel crankshaft without adequate damper.
All Cranks breaking at the front #2 journal which is same size journal as #6 , #6 is at rear of crank transferring all the power from the other 5 cyliners to gearbox - should snap there not #2. The torque converter is a big harmonic oil filled dampener that is why rear of crankshaft never breaks.
Need to dampen the front with gel damper!!!
Oh guess what else , spun bearings - this is a classic sign of broken or inadequate damper. 3rd/4th order Harmoics can cause crank to resonate and flex and then it picks up bearing and spins also blocking oil gallerys!!!
5kg+ gel/fluid damper!!!!
Cant believe no one has thought of this!!!
Look up harmonic dampers/ engine harmonics!!

If it were the case they would all be failing. Actual failure is around 1% so would be a lot higher if it was as you suggest.

Originally Posted by discoverypaul

Cant believe no one has thought of this!!!
Look up harmonic dampers/ engine harmonics!!

It has been thought of, but AFAIK not been implemented, https://www.facebook.com/Tdv6sdv6-Viscous-Harmonic-Damper-Interest-and-Discussion-384565665614752/'tsid=0.6841090610619096&source=result

I’m sure harmonics plus some poor machining/balancing is a factor, but not because the factory harmonic balancer is no good, but because the harmonics are accentuated through crank balance and design issues.
The poor radius of journal two as previously identified, plus possibly a less than good crank balance may cause the random failures were seeing. Breaking at the free end makes sense as it’s the “free” end where torsional flex is higher than compared to the gearbox end.

All speculation

240000klm on my "Discovery 4" here after "D4"

My D4 has been serviced every 6 months or there about's, The crank thing is a concern but what the hell I just live with it.

There are other more common issues that can be wallet damaging and I have had them happen.

• Split intake manifold (don't use an LR dealer for the fix find an indi)
• Split intake plenum crazy price for this part. I used a secondhand part
• Coolant cross over failure Easy Fix just do it
• AC compressor failures
• Torque converter issues

Stuff happens I keep fixing the old girl because its still cheaper than buying a new car at the moment.

[LIST][*]Split intake manifold (don't use an LR dealer for the fix find an indi)[*]Split intake plenum crazy price for this part. I used a secondhand part[*]Coolant cross over failure Easy Fix just do it[*]AC compressor failures[*]Torque converter issues

Both manifolds $1800 supply new and fit

The intake elbow is about $100 delivered from the uk. The Y piece a bit mire, but not hugely expensive.

Full service kit from X8R or similar around $150, no need to replace entire compressor.

New TC around $500, the cost is in the labour to get it out, whole transmission has to come out

agree, they are still worth fixing.