# Mercedes 609d or 709d ? What is the difference please?



## Niall McOwan

I really appreciate all the help to date and do feel appropriately simple for all the questions that are probably obvious!!
I'm looking at a 1993 Mercedes 609d race truck. 4000cc non turbo engine with 175 kilometres on the clock.
Family owned and maintained for moto cross. Looks a nice van.
The seller has said its a plodder 65 mph and gets you there with reasonable mpg.
They are changing to a quicker turbo'd , more fuel efficient van cause they are covering more and more of the country at weekends.
My questions is really what is your opinion of this model and can anyone tell me the difference between a 609d and a 709d please?
Phew!!  Thanks again


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## rolandrat

*Mercedes 609d or 709d ? what is the difference please?*

You will find that the only difference is the carrying capacity. The engines are bomb proof. Just have a very close look under the bonnet at the scuttle area and inner wings for severe tin worm. It could have been covered up with underseal.


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## Deleted member 3802

:ditto: :yeahthat:


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## paul h

as said above just weight issues i had a 709 years ago and they do go on for ever but non turbo does struggle up long hills .My truck does 60 on the limiter and after having fast cars and other vehicles find this a more relaxing drive in the truck


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## Byronic

My present van is a 709D self converted LWB owned for 16 years. The main thing to look out for is rust, especially the double skin sills, windscreen scuttle and pillars, they start rusting before they leave Stuttgart. I bought the 709D on the advice of mechanics who actually worked for MB in Stuttgart, the turbo versions according to them suffered more problems but still very reliable. The OM364 engine is just an updated version of the engine used in 508Ds etc never originally designed for turbo and turbo/intercooler.

The main difference between the 709d and the 609D are:

709D= 6.6 tonnes MGVW     609D=5.6 tonnes MGVW

The engines/gearboxes are exactly the same spec. the only differences mechanically are determined by the 1 tonne load carrying difference, ie the 609d has a higher diff ratio giving a max geared speed of 72mph whereas the 709D is geared for 63 mph. Tyre sizes differ 215 section as opposed to 225. 

Personally I would say the 609D is the preferred option, it's debatable whether the extra payload of the 709d is necessary for the average motorhome, and that extra massive 9mph is worth having!

The 609D ex factory weighs 3.3 tonnes approx that leaves 2.3 tonnes for the conversion work and payload.


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## Niall McOwan

*Thanks again.*

That's amazing knowledge there Byronic!! Many many thanks  to all.


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## BBBB

Byronic said:


> My present van is a 709D self converted LWB owned for 16 years. The main thing to look out for is rust, especially the double skin sills, windscreen scuttle and pillars, they start rusting before they leave Stuttgart. I bought the 709D on the advice of mechanics who actually worked for MB in Stuttgart, the turbo versions according to them suffered more problems but still very reliable. The OM364 engine is just an updated version of the engine used in 508Ds etc never originally designed for turbo and turbo/intercooler.
> 
> The main difference between the 709d and the 609D are:
> 
> 709D= 6.6 tonnes MGVW     609D=5.6 tonnes MGVW
> 
> The engines/gearboxes are exactly the same spec. the only differences mechanically are determined by the 1 tonne load carrying difference, ie the 609d has a higher diff ratio giving a max geared speed of 72mph whereas the 709D is geared for 63 mph. Tyre sizes differ 215 section as opposed to 225.
> 
> Personally I would say the 609D is the preferred option, it's debatable whether the extra payload of the 709d is necessary for the average motorhome, and that extra massive 9mph is worth having!
> 
> The 609D ex factory weighs 3.3 tonnes approx that leaves 2.3 tonnes for the conversion work and payload.





My 709d really struggles to go anywhere past 50mph - she's 1995, has a limiter and taco on her, is beautifully converted with wood and a burner etc ... any advice?  I don't especially want to burn masses of fuel ...


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## Byronic

BBBB said:


> My 709d really struggles to go anywhere past 50mph - she's 1995, has a limiter and taco on her, is beautifully converted with wood and a burner etc ... any advice?  I don't especially want to burn masses of fuel ...



As standard they are limited to 63mph which is the engine  maximum of 2800 rpm. If you exceed 63mph in 5th gear (only possible downhill!) then you're overreving the engine. My van will get to 63mph on the flat but I stick to 50mph,
or if the conditions allow even less. If your van can only manage 50mph on the flat then it must need looking at, the usual things injectors, compressions, pump etc. The only way to get more speed is to get the optional high ratio diff.
(best of luck with that one!) or the 609d rear axle but that could mean down plating to 5.6t due to it being a lighter duty axle.  
You could get a bolt on  low pressure turbo conversion but with no other mods to take care of extra heat and increased cyl. pressures etc. not recommended. Merc.themselves changed a lot of other the features on the standard engine when they added a turbo. Probably the most economical way of getting more power is an engine swap for an 364L turbo or 364LA turbo with intercooler. 
As far as I'm aware the 50mph red light indicator on the tacho is just an HGV speed warning and doesn't limit actual speed.
The fuel injector pump has a mechanical limiter set at 2800rpm. Which can get overridden (overevved)on a steep downhill 
as I've already stated. There were so many options and variations and changes it's difficult to be 100% certain of some spec. aspects. Anyway hope that helps not to confuse you!


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## caledonia

Ones slow and the others even slower. My mate has a merc ex library and it's embarrassingly slow and underpowered and maybe the engine is reliable but the old braking system and bodywork is a never ending struggle. It's also to big to hide away in a nice wild spot so he has to spend his time and money on campsite thingys. Oh and very noisy to travel in.


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## n brown

also check for rust all around the gutter line and the outriggers from the chassis


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## GWAYGWAY

The weight , I had a few 809 for a contract running mail to Holland and we used them   very reliable  and plods along but cuts DEAD at 55 mph like a brick wall the governor just will not allow more speed. The bigger engine one were even worse as they suckered you into  overtaking with loads of go, but also cut at the same speed whilst the driver was alongside whatever he thought he was overtaking.  It is exactly the same as modern electronic governers but purely mechanical.


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## Byronic

caledonia said:


> Ones slow and the others even slower. My mate has a merc ex library and it's embarrassingly slow and underpowered and maybe the engine is reliable but the old braking system and bodywork is a never ending struggle. It's also to big to hide away in a nice wild spot so he has to spend his time and money on campsite thingys. Oh and very noisy to travel in.



All true. However all can be overcome to some extent, for the noise, ear defenders, for lack of speed fit the 
glass fibre body skirt kit and stripes at least that makes it look faster than it really is!
Seriously though if you find you're not willing to overlook the negatives in favour of the positives 
then it's a fait accompli. 
However for me it's the other way round I like the rugged build of the thing, the simplicity,
the unpretentious commercial look, I hate the more florid wall papered look of some coachbuilts, they 
almost seem to invite attention, not something I look for when wilding. 
I appreciate the rear twin wheel drive, the tyres that never wear out (date out) the 22+ consecutive 
trips to the med. without notable incident, giving some credence to the bullet proof 
mechanical reputation, in my experience at least. The 2.3t payload that permits 
carrying a 200kg m/bike or a 125kg m/bike, both if I wished. The fact that in far flung
places older Type 2s are still much used as town busses...reassuring!
Even the 27.8 mpg isn't bad, and before anyone says oh yeah downhill with a following
wind, well for 3 years I kept accurate records purely for interest sake, the other 20 years
I hardly cared. The 24 hour parts service turnaround and the fact that many parts are 
still manufactured by OEM firms can't be bad. It's quite difficult to get these attributes in
one vehicle.
These are the things that are important to me in a M/home. I leave all the electronic stuff 
and 7 speed autobox for my change every 3 years warranteed car.


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