dennish

I'm looking at C32's to buy but several have been described as having a recent transmission flush. My indy merc mechanic is emphatic about NOT flushing. He states that this causes big problems. My wife's E430 has no TC drain. Ugh. We drained and refilled a second time to get out the more of the dirty fluid in the TC. Has anyone developed trans. problems due to flush?

Popo

I do my fluid replacements how you did it rather than a flush machine on my C55 and previous C32. never had any issues.

Is the reason for thinking about a flush to try to get 100% fluid changed? There is a youtube somewhere for the 722.6 showing how to do the flush using about 12 litres of fluid and disconnecting the cooler line.

I have heard (but do not know for sure) that pressure flush machines can screw up the transmission.

I'm doing a 722.9 fluid replacement next weekend when the parts arrive. It is more difficult due to the lack of a dipstick tube for filling.

ddtham

Talking from a Bimmer standpoint (might be applicable to MBs as well), it is not advisable to do transmission flush if the fluid is still original at more than 80K miles.

Some mechanics speculated that the fluid change at higher mileage will cause the metal deposits which were originally sitting harmlessly at the bottom of the pan to be displaced and lodged to different chambers in the transmission causing it to fail right after the change.

Periodic fluid change every 30K miles are encouraged however. I have changed ATF on my MBs religiously and has never encountered any issues (knock on wood).

If the car you're buying has a higher mileage and still at original fluid, there's a way for indie or dealer to look at the fluid and check if it's burnt or not. If it's burnt, it might be too late to change tranny fluid then.

Viper98912

I just did a drain and fill three times and like to think I got a majority of the old stuff out.

gt4awd

Last week did full transmission flush. Drain pan, replace filter, reinstall pan, add 5 liters fluid. Pull oil cooler line off transmission. Start car until it drains 3 liters. Takes about 15-20 seconds. Refill 3 liters. Repeat twice. Top off at correct level when transmission reaches 80C. Done... I hear people say a lot running the car to drain through cooler line is a bad idea. That's exactly how they do it at dealership. It's procedure listed in the service DVD.