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Need advice about V6 diesel faults!

miggit

Active Member
Joined
Mar 25, 2016
Messages
102
Location
Milton Keynes UK
Car
2000 ML270CDI Manual
We'll I'm in a bit of a pickle, my very long in the tooth ML270CDI is about to self destruct and I need to replace it.

So I was going to get a ML320cdi. And then I found out that they do NOT have a low range gearbox, D'OH!!

I tow Event Toilets about, so I need something that has a bit of grunt behind it, especially off road. So I hit Autotrader and have come to the only conclusion that a Jeep Grand Cherokee CRD will do what I need....
BUT, it's a Jeep:eek:, but it does have the Mercedes V6 CDi engine and I assume a Mercedes gearbox... so how bad can it be??

There is a lot of talk about injectors failing at around the 100k mark due to multiple firing at tickover to reduce diesel knock.. is this a Jeep thing or Mercedes thing?

I have also seen a bit about failing oil coolers, again is this common and how easy is it to do... yourself :wallbash: did I really just say that, Oh dear :confused:

And I've also been warned that they can suffer from backdeath... But that doesn't worry me, I can sniff out backdeath from 20 paces, I just haven't mastered getting the injectors to stay put in my worn out head:(.

I've been looking at a Jeep that's got 104k described as slightly smokey engine, and is at a price that I can afford to pack it off to my local Bosch Diesel Centre and have them pluck the injectors and repair as needed, gaining 6 good injectors and new seals without getting my hands dirty :)

So assuming that I can't detect backdeath, am I on to a solution or a one way trip to the fun farm?

Oh and I'm open to suggestions on cars.. just not a Range Rover... Had one, it ate recon gearboxes at the rate of 21k.. and a Discovery looks good until you see the lists of common faults... Land Rovers have never had good wiring, and the newer they get the more there is to go wrong, and it does!
Need something rated at 3.5 ton towing capacity and around 30 MPG when not towing, and it needs a proper low range gearbox!
 
If its anything like the Jeep/Mercedes the guy has at work then good luck! Ive never known a car to have so many issues.
Bodywork falling off, electrical gremlins and it eats tyres......
 
Discovery 1998-2004 model.... A colleague of mine has one , never let him down...Just rust is the main issue on the chassis.
 
A smokey engine could be a simple crankcase breather of a failing turbo, worn rings etc etc etc. Why consider a car with a known fault that is potentially expensive to fix?

For your needs a Landcruiser sounds ideal.
 
Landcruisers are great, but they do have a few shortfalls.... firstly they are priced as if they are made of gold and secondly they are very thirsty... I towed with Landcruisers for 8 years and I never got more than 25 MPG solo and 16 MPG towing. And don't believe anyone who says they don't break down... I've had some spectacular fails... front wheel drive flange gave way as I pulled on to a motorway roundabout, leaving me with no drive, with a 25 foot long trailer.. and I had a water pump give way without warning, sending the fan through the rad:eek:

As far as the Jap pickups go they have only been rated at 3.5 tons for a few years and I just can't afford newish:( everything that has enough power is rated at around 2.5 tons.

As far as Jeep reliability goes I would have said that they are less than perfect, but I was told by a member of the Range Rover forum it was the most reliable 4x4 he had owned... not sure if that's a good advert for Jeep or a very bad one for Land Rover:rolleyes:

Discovery 2 just hasn't got the power to tow what I have to day in, day out and the Discovery 3 has so many computers it makes my ML look stone age... even the manual has a sender unit in the gearbox and an ECU.. which goes wrong, and causes more than the on screen indicator to fail, WHY??

And my logic behind getting something with a known fault, is when the injectors are cleaned, tested and refurbed (as necessary) I would have a car with good injectors that should last another 100k, rather than a good example that will need the injectors overhauling at some point in the near future... lets face it they don't last forever and they are a serviceable item, albeit an expensive item and 100k seems to be about the service life of Bosch injectors.
 
X5 bimmers? Or a jeep early 2000 with manual transmission?
 
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I have also seen a bit about failing oil coolers, again is this common and how easy is it to do... yourself :wallbash: did I really just say that, Oh dear :confused:
As a V6 diesel owner (OM642) I was concerned about this (it is failing oil cooler seals) but my Indy said it isn't as common as people think - he said he had only done 4 so far and advised I stop worrying. Long job to do yourself though because of how much you need to strip off the top of the engine to get to them.
 
I went through a really bad patch with the V6 in my Vito at around 90k miles (I have owned it from new, FMBSH). Eight breakdowns (well, limp mode) over a period of about 8 months ... mostly different sensors failing, but also the EGR valve and (most costly) the turbo. That was caused by the manifold liners de-laminating and dropping debris into the turbo - this is a 'known issue' with the V6 in various MB models but apparently not that common so I guess I was just unlucky! Manifold replacement on the Vito is an engine out job.
 
X5 bimmers? Or a jeep early 2000 with manual transmission?

X5 BMW has the same feeble gearbox as the Range Rover... they last a little longer than the Range Rover as the X5 is 1/2 ton lighter, and as far as I'm aware they have only a high range gearbox... so they are a toy, not a serious offroader.
As for the Jeeps the only manuals they made were the Cherokee and the Wrangler... the 2000's are only plated for 2 tons.
It is a very small list of vehicles that are legal to tow 3.5 tons and an even smaller list of those that are manual...
Landcruisers - silly money.
Discovery's either not enough power or too many things to go wrong and enough power... I have discovered that the gubbins that they stick in the manual gearbox also measures clutch slip... get a too enthusiastic with the loud peddle and you are in instant limp mode... doesn't bode well if you're trying to do a hill start with a heavy trailer..
Ssssang Yyyyong things, I wouldn't buy a motor that I couldn't pronounce the name properly;)
And my trusty, but very well worn manual ML 270 CDI... which are like rocking horse poo to find, especially with sensible mileage. And if I'm totally honest the rear suspension really doesn't like the bashing that I give it... and that is with NEW +30% springs and dampers, plus the setup isn't user friendly when it comes to up-rating, basically you can't:(

So I'm forced to get an automatic:mad:... would love an ML320CDI.... but Mercedes have decided that they are going to make a toy, not a real 4x4.

That is why I'm looking at a Grand Cherokee, granted it has the build quality of a poorly assembled Airfix kit, so I will be expecting to stick it back together... but it does have Mercedes underpinnings so it should be better than their first diesel which had a VM :eek:

Larkone, thanks for the info, I only raised it as it was mentioned on a Jeep forum... along with lots of moaning about the price, just under £300 from Chrysler... that panicked me a bit, but then I hit the parts manuals and it bares more than a striking resemblance to the V6 sprinter oil cooler.. which I found new, with 2 year warranty, for about £60!

BTB 500, also thanks, from what I can see the worn injector is a Jeep issue, they must use a different engine map.
 
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Have a neighbour who runs a garage and works on a lot of Discoverys - his comment was it is embarrassing talking to customers because almost every major fault costs around £2500 to fix.

Re the oil cooler, it is advised to change the oil cooler when the seals go as a precaution but the actual seals are only a couple of quid. Its the 10+ hours to do the job that costs.
 
^ funny that... I found the same thing with the Range Rover... gearbox 2.5k, another gearbox 2.5k, front struts and air compressor only came in at 1k (got off lightly there:rolleyes:) and the list goes on...

RE oil cooler, I think that a few Jeep owners reach for the rad weld when things start to go wrong which causes blockages... or it could be the wrong anti freeze / water? don't know how fussy they are... the Range Rover needs Tibetan mineral water, that is raised and bottled by Virgins, from the upper slopes of Everest... that soon adds up !
 
Does any body know anything about the swirl flaps? and can they be deleted like on the 270cdi?...... Best mod I ever did to my ML, do away with the little gits!!
 
Yes - 4.7k ohm resistor in the two centre connections on the plug.
 
The GL has low range and you can lock the diffs, I have one, it’s a good piece of kit
 

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