W212 Rusty sump pan (pans!) woes - Oil pan and transmission pan

[John N]

Do you think the rust indicated by the poor photo in the original post is too far gone?
I'm not too bothered by how long it might take to do a good job, but more about the cost at this point.

Whilst I do usually maintain my cars regardless of cost, it's been an expensive end/beginning to the year with 4x new winter tyres, new radiator and all hoses, new expansion tank, new PAS reservoir, DIY engine and diff oil change, a garage service and MOT (including another engine oil change) with ATF change plus new ATF sump pan, new transmission oil line, rear ride height sensor, air and cabin filters, fuel filter, batwing and all the seals on the air charging pipework. We're talking heading towards £3k even with the bulk of that being DIY.
And with some suspension components and a new engine oil pan on the horizon, it's stretching the pay packet a little right now.

I MAY be picking up the "Wrong Vibes" here, but I am under the impression that BlackC55 was hinting about the fact that if the Sump "fluid leaks out at a dramatic rate" it's "Game Over"

I stand corrected if not!

 

[Bellow]

A garage proprietor once told me that the crucial stage is when the steel starts to 'flake'. Unaddressed, more water and salt permeate under the flakes and corrosion from that point is accelerated. He was talking about subframes and the likes but steel is steel.

 

[BlackC55]

I MAY be picking up the "Wrong Vibes" here, but I am under the impression that BlackC55 was hinting about the fact that if the Sump "fluid leaks out at a dramatic rate" it's "Game Over"

I stand corrected if not!

The car will stop moving forward if the gearbox sump pan leaks. Permanent damage is unlikely as long as you don't attempt to drive with lack of ATF.

 

[MrGreedy]

Gearbox sump pan is replaced as that was only £69 extra during ATF fluid change.

Engine will of course quickly meet it's end if the engine oil sump pan develops a hole.
I'll report back in Spring when I've rotary wire brushed the rust off. If it's superficial, no problem.
If it's terminal and I find a hole, I'll have to get trailered to the garage to replace the pan as that's definately not DIY.

 

[Railwayman]

Gearbox sump pan is replaced as that was only £69 extra during ATF fluid change.

Engine will of course quickly meet it's end if the engine oil sump pan develops a hole.
I'll report back in Spring when I've rotary wire brushed the rust off. If it's superficial, no problem.
If it's terminal and I find a hole, I'll have to get trailered to the garage to replace the pan as that's definately not DIY.

Gearbox sump pan is replaced as that was only £69 extra during ATF fluid change.

Engine will of course quickly meet it's end if the engine oil sump pan develops a hole.
I'll report back in Spring when I've rotary wire brushed the rust off. If it's superficial, no problem.
If it's terminal and I find a hole, I'll have to get trailered to the garage to replace the pan as that's definately not DIY.

Sounds right to me, in the meantime I would apply a liberal coat of protective grease to the area to prevent further damage till spring. I've found that something like copper grease is quite good at staying in place and resists washing off quite well.

 

[John N]

The car will stop moving forward if the gearbox sump pan leaks. Permanent damage is unlikely as long as you don't attempt to drive with lack of ATF.

I was referring to the Main Oil Sump Pan!

 

[Justintyme]

Unluckily for me, from today's inspection at the independent Merc Specialist, both my transmission sump pan and my oil pan are rusty in specific places, with badly breached (missing) paint.
The transmission pan is really rusty around the drain plug hole.
The oil pan is really, really rusty around the oil level sensor hole.

I've had a new transmission pan fitted today as the car was in for an ATF change (last service was 4 years, 20k miles ago).
Original part number A2222700512, now replaced with A9062700501 (£69 for the part only for the specialist to fit, as obviously the old one was off for the fluid change).
Price seems pretty reasonable, as there are a good few used, genuine MB ones in not pristine condition available on eBay for £50 plus shipping. Who would pay that?

The oil pan (part No. A6420102028) is recommended to be replaced next year at the oil change.
Unfortunately, the part looks to be £250-300, judging by genuine Merc new sump pans for sale on eBay.
Double unfortunately is this isn't really an easy DIY, as engine lifting/subframe lowering required to get the pan out.
Because this isn't a DIY, I'm restricted to a new pan because understandably, the specialist won't fit used parts.

I try not to drive through puddles. All undertrays are intact and fitted.
I'm a bit surprised that both of these need changing.
Might be worth a close look if you DIY your car.
Mine is very late 2011, so only 12 years young.

Both pans rusty, but not leaking MrGreedy? Just like missing paint and rust coloured patches? Because if its just exposed metal, a good clean down, some primer, a new coat of paint and off you go again. Obviously, won't work though if the pan is warped or otherwise damaged.

 

[Justintyme]

My diesel engine bay smells fresher than the inside of the car

That would depend on what kind of work you have done before sitting into the car..the SIL is a farmer, and for sure, getting into his car, never mind travelling in it, requires an effort of will...