Why do 2.7 cranks break?

**4bee** · 26th November 2021, 07:13 PM

Originally Posted by scarry

Starting an engine when its cold is generally when the most wear occurs.An engine that never stops or never gets a chance to cool down,should last the longest.

Synthetic oils help to reduce this wear.

Have a look at this.

The Million-Mile 2007 Toyota Tundra Pickup: The Teardown

Paul, been meaning to ask about your S1.re mileage, engine condition, other mechanicals, history etc.

How about a short rundown please?

**DiscoDB** · 26th November 2021, 07:42 PM

So this is the list of some of the changes that Ford made for the 3.0 Powerstroke:

- A new forged crankshaft.
- New bearings using different materials.
- Dual stage oil pump.
- Tuned crankshaft damper.
- Revised build tolerances, fillet specs, heat treatment etc.

Add to this we know the oil pump had previously been upgraded for the 2.7 (strengthened and increased oil flow rate), plus the 3.0 got locating tabs on the main bearings.

From this we can conclude the Ford engineers came to the same conclusions as most of the theories out there.

The new Ford Ranger sounds like it will be getting a decent engine after almost 20 years.

**Tins** · 26th November 2021, 08:16 PM

Originally Posted by DiscoDB

So this is the list of some of the changes that Ford made for the 3.0 Powerstroke:

- A new forged crankshaft.
- New bearings using different materials.
- Dual stage oil pump.
- Tuned crankshaft damper.
- Revised build tolerances, fillet specs, heat treatment etc.

Add to this we know the oil pump had previously been upgraded for the 2.7 (strengthened and increased oil flow rate), plus the 3.0 got locating tabs on the main bearings.

From this we can conclude the Ford engineers came to the same conclusions as most of the theories out there.

The new Ford Ranger sounds like it will be getting a decent engine after almost 20 years.

They also going to use it in the new Amarok and whatever they call it in the US?

**scarry** · 26th November 2021, 08:40 PM

Originally Posted by 4bee

Paul, been meaning to ask about your S1.re mileage, engine condition, other mechanicals, history etc.

How about a short rundown please?

No worries,

It has a heap of history.

I will do it in the S1 section,and tag you in.
A bit off topic for this thread

**Tombie** · 26th November 2021, 09:39 PM

Originally Posted by DiscoDB

By comparison, this is from the Citroen C6 2005 Handbook. In this case the diesel is the 2.7 without DPF.

Interesting that for “temperate” to “hot” climates they recommend a Semi Synthetic 10W-40 oil to ACEA B3 spec.

For most of us here in Australia, the HPR 5 or HPR Diesel 5 looks to be the best choice.

Just because it’s the same engine doesn’t mean it isn’t assembled market specific.

Could easily have different pistons, rings, bearings etc. even different tolerances.

Don’t just go by the designation.

**PerthDisco** · 26th November 2021, 09:42 PM

Originally Posted by Tombie

Just because it’s the same engine doesn’t mean it isn’t assembled market specific.

Could easily have different pistons, rings, bearings etc. even different tolerances.

Don’t just go by the designation.

The Citroen’s do have the thermostat in the top plastic fitting that is confusingly referred to as the thermostat on the LR TDV6

**incisor** · 26th November 2021, 10:15 PM

as an aside, when did the uprated oil pump with the heavier boss, uprated flow etc become available ?

**PerthDisco** · 26th November 2021, 10:18 PM

Originally Posted by incisor

as an aside, when did the uprated oil pump with the heavier boss, uprated flow etc become available ?

The updated oil pump after MY08

**Tins** · 26th November 2021, 11:22 PM

This is a fascinating thread. I'm going to give my TD5 a little pat on the head tomorrow.

The ZF 4 speed not so much

, although the one I have now seems pretty OK.....

**DiscoDB** · 27th November 2021, 09:15 AM

Originally Posted by Tombie

Just because it’s the same engine doesn’t mean it isn’t assembled market specific.

Could easily have different pistons, rings, bearings etc. even different tolerances.

Don’t just go by the designation.

From what I have read the bottom end is common. Bearings are matched to the crank and block, but share the same parts between Ford, Jaguar, Peugeot and Citroen.

It is possible that PSA said let JLR have the tight fit tolerances, and give us all the sloppy bits and we will just use a thicker oil in hot climates, but I doubt it.

. (I am just joking - in reality this is possible as there is a sound basis to optimising clearance tolerances with oil specs and the JLR and PSA engineers may have been divided on this one).

I believe the reason for the differences in oil specs is Ford actually specify a Ford standard (913

but then each car manufacturer has their own supply agreements with different oil suppliers who then together select an appropriate best match to the Ford spec for the market they operate in.

Most of the differences are subtle and relate to oil standards which are compatible with each other, but Citroen look to put more effort into matching the oil spec to the climate conditions being operated in and as such suggest a broader range of oils use.

If operating in warm to hot climates, I personally wouldn’t use 5W-30 and feel the 5W-40 is the better option. I am also not convinced that we should use a true A5/B5 spec oil, but comfortable knowing that A3/B4 is a compatible alternative and meets both Land Rover’s and Citroen’s specs and should offer better wear protection.

However, if you believe that thicker oil can cause a bearing to spin at high revs, then I understand why a low friction / low viscosity 5W-30 A5/B5 spec oil is being recommended by Ford and Land Rover, and even Citroen for cold climates. I am yet to be convinced on this but I get the theory.

On this one you really need to select which theory you believe is more credible - if in doubt just follow the recommendation in the owners manual.

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