4 replies to this topic

[Tibbles Stryker]

Hi guys, As always I like a little reassurance and help prior to doing maintenance to cars that I'm still learning about. I have a bmw x3 3.0d it's knocking on with 110k although is pretty dam perfect. I have changed the transfer case oil and also both diff oils and I'm seeing an improvement on the way the car drives so next job is the transmission fluid. It's a six speed auto and bmw states lifetime oil do not change, now I'm considering draining the atf, remove the sump, clean and replace filter then refill, obviously it'll not completely empty the system (probably half the oil) but should help and not disturb any harmless sludge that will be tucked away. I've spoken to leek transmissions and they recommend a full flush and refill however after reading many forums many people say not to flush as it will dislodge the sludge and could cause more issues longterm. Has anyone any knowledge on this topic or recommend the best path moving forward? Opinions appreciated 👍

[fezzasus]

very unlikely you'll develop any sludge in the transmission using modern lubricants.

[JG]

yeah, you'll just make it worse. leave it well alone. 

 

The transmission oil in our mercedes 7G-tronic has just been changed at vast cost because it had reached the manufacturer recommendation for change. 

 

There is no discernible difference at all. 

[Tibbles Stryker]

Thanks guys, preventative maintenance is not always a good thing I suppose 👍

[Nev]

I doubt many gearboxes (if that's what you mean by transmission) would benefit from an oil change until at least 150k miles, the wear and tear in a gearbox is minimal compared to an engine as it is a completely closed environment with 0 contaminants.

Edited by Nev, 31 August 2016 - 09:47 AM.