Engine oil in the transmission fluid

DizzyGlobe

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A few days ago I was driving my 16 year old C200 CDi diesel auto estate. It was running great but the next minute came to a stop on a hill and rolled back despite being in drive. I managed to get it home after another 5 stops. I could rev it to 5000 without and movement. I kept on doing transmission resets and got it home.

On checking the transmission fluid level it was was way above the maximum level. It seems engine oil has managed to get into the transmission.

To further complicate matters the coolant level had fallen and needed a litre to fill up. The coolant had an oily film on it too.

Any suggestions would be appreciated. Should I scrap what is otherwise a nice car?

Thanks for reading
 

alexanderfoti

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I would think coolant ha entered the gearbox via a failed radiator, and that its not engine oil in your gearbox.

A flush and a new radiator may be sufficient, but you may still have clunky gear changes afterwards
 
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DizzyGlobe

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Thanks for the advice - I will look for a radiator.
 
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DizzyGlobe

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And you need to do an auto gearbox flush out .Then replace with new filter and new oil
Do you know the exact amount of transmission fluid? When I drain from the gearbox the oil will be mixed with water so the volume is much greater than it should be.

Thanks
 

pgh13

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Do you know the exact amount of transmission fluid? When I drain from the gearbox the oil will be mixed with water so the volume is much greater than it should be.

Thanks
You'll need a dipstick to set the level, but they are cheap on Am.... Etc.
I'd put a couple of litres and go from there. There's a more fluid in the torque converter and cooler circuit, but as you're replacing the rad that accounts for that.
I've flushed mine a couple of times by disconnecting the return from the cooler. Start the engine and about 2l will come out and then it'll stop. Stop the engine, add another 2l, then start the engine again. Repeat until fluid looks cleaner. I found a piece of standard garden hose fits over the detached coupling allowing it to be directed into suitable container.

You need to set the final level with engine running and transmission up to temperature
 
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DizzyGlobe

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You'll need a dipstick to set the level, but they are cheap on Am.... Etc.
I'd put a couple of litres and go from there. There's a more fluid in the torque converter and cooler circuit, but as you're replacing the rad that accounts for that.
I've flushed mine a couple of times by disconnecting the return from the cooler. Start the engine and about 2l will come out and then it'll stop. Stop the engine, add another 2l, then start the engine again. Repeat until fluid looks cleaner. I found a piece of standard garden hose fits over the detached coupling allowing it to be directed into suitable container.

You need to set the final level with engine running and transmission up to temperature
Thanks for taking the time to reply to me. Your information is appreciated.
 

pgh13

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It's cheaper to buy in 20l as you'll need a fair amount.
I've used this for the last 4 yrs with no problems; That's for the 5 speed box. Currently £99.99 delivered.
 

AnthonyUK

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Do you know the exact amount of transmission fluid? When I drain from the gearbox the oil will be mixed with water so the volume is much greater than it should be.

Thanks
It is around 7-8l but as mentioned you may need to flush too.. Your transmission fluid is contaminated with coolant not gearbox oil.
The glycol can destroy the friction plates unfortunately.
 
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DizzyGlobe

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Thanks for your reply. I hope I have been lucky and no glycol problems.
 

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