Why do 2.7 cranks break?

**101RRS** · 25th November 2021, 07:31 PM

Originally Posted by DiscoDB

From what is known they did redesign the crank and bearings, and changed the oil spec. But they may have potentially also made other changes to the lubrication system and even the crankshaft damper/balancing to mitigate the weaknesses of the 2.7/3.0.

So most, if not all, of the contributing factors sound like they should have been addressed. Would be good to see the full details on the design changes made. I bet it is a long list.

Good news is the 3.0 Powerstroke has been confirmed for the new Ranger so we may yet find out more on what Ford did to improve the reliability of the engine. Ford will still need to explain more to address any reliability concerns given the same engine was discontinued for the F-150 after only 3 years.

Yes they simply made the journals a couple of mm thicker so it is now strong enough so it doesn't break.

**Tins** · 25th November 2021, 07:46 PM

Originally Posted by Homestar

The Ford badge screwed to the rocker cover provides superior reinforcement than the Land Rover badge…

Why? They're both oval....

**PerthDisco** · 25th November 2021, 08:05 PM

Originally Posted by 101RRS

Yes they simply made the journals a couple of mm thicker so it is now strong enough so it doesn't break.

I keep bashing on about this and maybe I’m wrong but I propose that the crank breaks after the bearings shag out and maybe rotate but only sometimes as many just get the death rattle. I guess 8/10 owners don’t pick up on change of note and drive on till it seizes at a bearing and snaps the crank. Or if it happens at 100kph it’s pretty instantaneous.

**ramblingboy42** · 25th November 2021, 08:05 PM

Someone said something about inherent weakness in V6 engines....

Really? How many V6 engines are pulling road trains around this country? I've not heard of any exploding.

Truckies comments welcome.

**DiscoDB** · 25th November 2021, 08:58 PM

Originally Posted by ramblingboy42

Someone said something about inherent weakness in V6 engines....

Really? How many V6 engines are pulling road trains around this country? I've not heard of any exploding.

Truckies comments welcome.

V6 absolutely can be built tough. But they are just one of the worse for harmonics and balancing which induces flexing of the crank. All of this can be designed out - Ford/PSA just pushed the boundaries too far.

**DiscoDB** · 25th November 2021, 09:18 PM

Originally Posted by PerthDisco

I keep bashing on about this and maybe I’m wrong but I propose that the crank breaks after the bearings shag out and maybe rotate but only sometimes as many just get the death rattle. I guess 8/10 owners don’t pick up on change of note and drive on till it seizes at a bearing and snaps the crank. Or if it happens at 100kph it’s pretty instantaneous.

Given we can’t just change the crank, the spun bearing induced failure is probably the one failure mode that we can be most alert to.

**Discodicky** · 26th November 2021, 06:49 AM

No one has brought up the suggestion that the broken cranks are subject to a manufacturing problem/defect such as machining/heat treatment etc which was recognised/remedied and LR is aware of the range of engine Serial numbers which are applicable?

No doubt there'd be an LR Service News relating to this if in fact it was the problem.

**scarry** · 26th November 2021, 07:11 AM

Originally Posted by Discodicky

No doubt there'd be an LR Service News relating to this if in fact it was the problem.

Maybe not,I can guarantee they know a lot more about the issue than anyone else,apart from the engine manufacturer.

If it’s not a safety issue,and it’s going to cost huge $$ to sort,wouldn’t they stay quiet ,which is what they have done?

**Tombie** · 26th November 2021, 07:42 AM

Originally Posted by DiscoDB

When you change the oil and filter it feels like an eternity waiting for the oil pressure light to go out.

Really?

Mines out in under a second.

**PerthDisco** · 26th November 2021, 07:53 AM

Originally Posted by Tombie

Really?

Mines out in under a second.

For sure it’s double the time of a normal start up after an oil and filter change for me but measured in seconds though.

Through this learning curve I’ve been conscious of how much cranking on startup. With the latest battery I put in it’s semi-instantaneous. In the darkest coldest winter morning I maybe sense it cranking before starting.

I do think for those in colder parts of Vic would be advised to change glow plugs on older cars.

Thread: Why do 2.7 cranks break?

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