So Ive been offered a free D3

[Blknight.aus]

Someone out of the blue has offered me a free D3,

PRoblem is it apparently has a blown oil cooler.


How much heartache am I in for to sort this or am i better off parting it out?

[loanrangie]

If thats the only issue then someone with your certain set of skills wont have a problem fixing it, time and space is all you need.

[Jeffoir]

Hi Blknight,

I worked with my Indie to replace the oil cooler in our 2012 D4 with 280,000 kms, last Christmas. It was not too difficult. The Indie said that the D3 is an easier job than the D4. There are videos on You Tube.

We used an aftermarket Nissens oil cooler. Economical and reliable.

If oil has contaminated the coolant sysytem, this will need flushing. The top hose is where a lot of the oil will rise to. I replaced it. Also, the coolant bottle, with its compartments, traps oil. I replaced it after flushing. I did all of this part myself. I used Cummins Fleetguard Restore to emulsify and flush the oil. Brad C put me onto this product. This is a high strength Potassium Hydroxide (strong alkali) solution. It did an excellent job. I made two flushes with extensive rinsing between. An aftermarket coolant bottle is not very expensive.

Best wishes, Jeff

[loanrangie]

Hi Blknight,

I worked with my Indie to replace the oil cooler in our 2012 D4 with 280,000 kms, last Christmas. It was not too difficult. The Indie said that the D3 is an easier job than the D4. There are videos on You Tube.

We used an aftermarket Nissens oil cooler. Economical and reliable.

If oil has contaminated the coolant sysytem, this will need flushing. The top hose is where a lot of the oil will rise to. I replaced it. Also, the coolant bottle, with its compartments, traps oil. I replaced it after flushing. I did all of this part myself. I used Cummins Fleetguard Restore to emulsify and flush the oil. Brad C put me onto this product. This is a high strength Potassium Hydroxide (strong alkali) solution. It did an excellent job. I made two flushes with extensive rinsing between. An aftermarket coolant bottle is not very expensive.

Best wishes, Jeff

Nissens is OEM so its a good choice.

[DazzaTD5]

As the engine oil cooler can either leak externally filling the V of the engine with engine oil and/or leak internally putting engine oil into the cooling system.

If the later then once the job is done clean the cooling system as much as you can, do a bit of driving as its going to require numerous go's to get it clean, until then forget running coolant just fill with tap water or distilled.

Once clean, you will need to replace all the coolant hoses, expansion tank, cap, water pump as you will run the risk of all these items failing at some point. Cooling system are not designed to have hydrocarbon in them.

[Lionelgee]

Hello All,

I had a Jeep Commander fitted with the Mercedes V6 Diesel OM642. When the Jeep was made it was manufactured by Chrysler Daimler - hence the Merc diesel. As per some experiential learning - learning from experience, the oil seals on these motors blowing is case of 'when' not 'if'. Oil through the coolant lines throughout the engine. Then pumped out through the overflow tank spreading out everywhere. No warning at all. The following link runs through the replacement of the seals .... accessed 20th August 2025 from, https://www.youtube.com/watch?v=yDDPajzdlrU&t=358s

My mechanic replaced all the parts in the cooling system that could be easily removed and new parts fitted - including all the parts that Dazza suggested and then some more. The mechanic told me that there could be a couple of two dollar 'o' rings located deep in the motor that were designed only to handle coolant - never oil. I was advised that these cheap 'O' rings were compromised and could just give way without warning at any moment and have catastrophic results. It was recommended that I hold on to the car for a reasonable amount of time and then get rid of it. Its fate was sealed [no pun intended] when the starter motor went a couple of months after the major repair. I thought that replacing a starter motor would be a trivial thing to do. I located the starter motor and noticed its lack of ready access, so I paid a professional to suffer the inconvenience. It was the last straw - so off to the a local car yard it went.

The engine is a crate motor. Designed to fit into a specific space within sedans to vans and four wheel drives. Pity any poor sod who comes along and tries to do maintenance and repairs. The thought of driving somewhere like over the Gateway Bridge and having a $2 o'ring go and then not long after the motor self destructing just preyed on my mind too much. For some strange reason I expected reliability in the most expensive vehicle I had ever owned. Instead, it paid me back by providing the most expensive mechanical repair bill I have ever had to pay. Goodbye money pit!

A couple of mechanics recommended getting Fairy dishwasher tablets and filling the radiator with water and using the Fairy to clean out all the oil within the coolant system. Drive until it comes up to full operating temperature. Then drain and hose out - keep doing the Fairy until the lines run clear. Rinse and repeat.

Kind regards
Lionel

[loanrangie]

Whats the general condition and mileage, age, spec etc ?

[Tins]

There's currently a decent 2.7 Territory on MP for $3K... Well, there was yesterday. I'll see if I can find it.

[Tins]

The one I was thinking of seems to be gone, but there's this.

[Tins]

Here it is