diff oil change yes or no?

[tony jr]

W163 ML270 cdi 2003 114K miles
I have been reading online all your views regarding ‘sealed for life’ automatic gear box and what this really means i.e. safe to just get past warranty period! This got me thinking is this the same for the rest of the transmission and should I look to change the front and rear differential oil say every 50K miles and maybe the transfer case as well. I assume this is just a case of draining the oil via the drain plug and filling back up with fresh oil till it starts to run out of the fill plug. If this is the case what oil (synthetic?) would you recommend (75W85 or 75W90 or 80W90 any thoughts?) and how much would I need for each diff? Is this worth doing? I also presume the transfer case take normal std automatic transmission fluid - is that correct? I assume with the ml I would have enough clearance to get access without the need to jack the car up on ramps. I have checked in the owners manual and none of this info is listed so would appreciate it if anyone can confirm what the oil grade should be, the MB spec and how much I will need.

Thanks in advance

tony

 

[steve333]

Hi Tony,i would definately change the diff oil at your mileage whatever mb say about sealed for life,as far as the transfer casings,one of the experts will i'm sure help you with that

 

[philepo]

No. Waste of time and money, unless this feeds your inner OCD cravings?
Oil in diffs and manual boxes has a very easy life.

 

[SilverSaloon]

for the cost, i'd change it if you plan to keep the car for atleast a few more years.

 

[kwakdonut]

No. Waste of time and money, unless this feeds your inner OCD cravings?
Oil in diffs and manual boxes has a very easy life.

And how do you come to that conclusion???

No gearbox has an 'easy' life per se.

It's a relatively cheap and easy job to do and gives you the satisfaction that it has been done, so no harm in it really

 

[Howard]

No. Waste of time and money, unless this feeds your inner OCD cravings?
Oil in diffs and manual boxes has a very easy life.

It's an autobox.

After my ATF was changed , the car changes gear noticeably smoother.

 

[Rovinghawk]

Filled for life.

Drained & refilled for longer life. Mine was changed at 100k & I feel a lot happier for it having seen the rancid crap that came out of the diff.

RH

 

[Smiley]

No. Waste of time and money, unless this feeds your inner OCD cravings?
Oil in diffs and manual boxes has a very easy life.

which is why it is not changed every 12 months. But after 5+ years and 100k miles all lubes on the planet will have degraded to some extent - therefore for a relatively small outlay it is worth changing the fluids imho.

 

[jaymanek]

I would agree that to an extent Diff Oil doesnt need to be changed with any regularity... It goes orrible the minute its replaced anyway... I would however at least check its level once in a while as they do tend to froth a bit of it away...

That said I change mine every two years without fail just for the satisfaction of it... its only a litre of a reltively cheap oil anyway.

Gearbox oil is in a different league altogether... especially Auto transmission...

 

[philepo]

And how do you come to that conclusion???

No gearbox has an 'easy' life per se.

It's a relatively cheap and easy job to do and gives you the satisfaction that it has been done, so no harm in it really

Autobox, yes go for it, transmission cluthes wear producing heat and debris so it makes sense. Hving said that mines done 140k and is smooth as you like with no oil changes done.

Manual box or diffs, for satisfaction, yes. In reality, no.

These do have an easy life in that they are free from combustion contaminents and extreme heat.

But for shear satisfaction, go for it.

 

[RBYCC]

As far as the auto transmission, ask any C43 owner with the revolutionary "sealed for life" transmission.
Failures began around 60K miles, of course beyond the warranty !!!
Important with the auto box is also to change the filter screen.

As far as the diff, I would do it every 40K miles along with the auto trans.

On my CLK63 Black Series, Merc warranty requires the diff and the diff cooler to be drained and filled within the first 3K miles.

 

[Satch]

One very good reason to change oil in differentials after extended use is that all Extreme Pressure lubricants will over time use up their additive packages which is actually what provides the required degree of protection rather than the oil itself.

Also diffs. tend not to have filters and simply recirculate wear particles.

General rule of thumb I have always applied is 5 years or 80.000 miles, although some vehicles will have requirements for a shorter change interval, especially off road and high performance.

 

[Setanta]

I would say change it.

In fact, am getting Olly at PCS to do it for me anyways

Prevention cheaper than the cure!

 

[Ted]

If you do change it, make sure that you can remove the filler plug BEFORE you remove the drain plug

 

[Rovinghawk]

But for shear satisfaction, go for it.

That's quite clever, actually.

RH

 

[kwakdonut]

Autobox, yes go for it, transmission cluthes wear producing heat and debris so it makes sense. Hving said that mines done 140k and is smooth as you like with no oil changes done.

Manual box or diffs, for satisfaction, yes. In reality, no.

These do have an easy life in that they are free from combustion contaminents and extreme heat.

But for shear satisfaction, go for it.

Have you seen how much swarf is produced on a 'crunched' gearchange in a manual??

I would change the gearbox oil of a reasonably high mileage manual car - in fact, I plan to do it on my current car as it has 125k on the clock, it takes less than 2L of oil and will take me probably 1/2 hour max....

 

[philepo]

Have you seen how much swarf is produced on a 'crunched' gearchange in a manual??.......

It's only my opinion.

If the swarf is that bad, then the box is doomed. If its minor then it will not be recirculating arounf the cogs wearing away as that would be catastrophic. It will be picked up and held by a magnet, usually the sump plug.

All I'm saying is if you change the oil every 50 k for peice of mind great, but if you would rather talk to your missus and play with the kids than spend saturday swearing at a stuck sump plug, then leave it, it will last the life of the car! (Probably)

To be serious, what do MB recommend?

 

[kwakdonut]

It's only my opinion.

If the swarf is that bad, then the box is doomed. If its minor then it will not be recirculating arounf the cogs wearing away as that would be catastrophic. It will be picked up and held by a magnet, usually the sump plug.

All I'm saying is if you change the oil every 50 k for peice of mind great, but if you would rather talk to your missus and play with the kids than spend saturday swearing at a stuck sump plug, then leave it, it will last the life of the car! (Probably)

To be serious, what do MB recommend?

You are very welcome to your opinion!

Mine is based on fact as I am a Mechanical Engineer.

Not sure what MB would recommend (let's face it, until very recently all the autoboxes were 'sealed' for life' and lo and behold, they now require at least a one-time change at 40-odd thousand). But for peace of mind, especially if you buy a high-mileage vehicle or intend to keep it for a while, then an hour or two changing the gearbox and/or diff oils will bring a little peace of mind.

Then you can go play with the wife and kids!

I am a great one for preventative maintenance rather than letting something more catastrophic, which may well have been avoided, happen

 

[philepo]

You are very welcome to your opinion!

Mine is based on fact as I am a Mechanical Engineer.....

Snap! :bannana:

I'm not saying you're wrong, just that you're not defo right. There are cars like mine with 140+ k with no oil change that run peachy because the oil is very lowly stressed in a cool and combustion contaminant free environ.

Peice of mind and pottering pleaseure, yes.

For sound eng reasons, IMHP no.

 

[Rovinghawk]

To be serious, what do MB recommend?

Buy a new car or at least new parts. This is more likely when the old one is knackered through lack of oil changes in its life.

RH