I am in the final stages of servicing a newly-acquired 2000 CLK430 (40,000Mi.) and am now up to the automatic transmission. Mercedes says it "requires no service" but, after I pressed them on the issue, agreed to drain and refill the fluid and replace the filter for $269. Seems awfully high to me.

A local, reputable shop has recommended I have them perform a "transmisssion flush". In this procedure, the pan isn't dropped at all, but lines are connected to the trans and a chemical solution is circulated to flush out contaminents.The filter is not changed, which is a major concern to me.Of course, if the system is reverse-flushed (they weren't sure about this), then it might make sense.

Needless to say, I'm pretty skeptical, but the service manager is an ex-Mercedes guy and also was a transmission mechanic earlier in his career. I have good experience with this shop in the past, but this is a new level for me. I know this procedure has been around for a number of years, but have never met anyone who has used it.

Anyone out there have any experience with this?

Thanks.
Frank

I've talked with a indie shop in the DC area and their version of a "flush" was to drain the fluid in the veicel > fill it up again > then run the vehicle for a bit [ ? 30 -50 miles] then drain that fluid and then fill up the tranny fluid once more > they chnage the filter ..

I would think any process that does not change the filter is flawed...

Personally > I did the job myself > drain pan and torque converter and chnge filter..

Most reputable shops will recommend only a drain and fill, not power flushing. There are lots of little passages in a tranny that could get blocked if particles get lifted and moved in a high pressure flush.

Stick with drain and fill.

Troy
1995 E420 96k

I have done it both ways...but stopped the flushing after it caused a problem in a Q45 some years ago.

I just drain, change filter and replace now. Make sure you do the torque converter if you have a drain bolt plug.

I also use synthetic Mobil 1. Don't know if it's any better, but since you are keeping it in for 30k miles, the cost per mile isn't too bad.

__________________
1989 300ce 129k
( facelifted front,updated tail lights, lowered suspension,bilstein sports, lorinser front spoiler, MOMO steering wheel, remus exhaust,stainless steel brake lines). (Gone)

1997 s320 154k (what a ride). Sold with 179k miles. Replaced with Hyundai Equus

1994 e320 Cabriolet 108k



1972 280se 4.5 153k Owned for 12 yrs, sorry I sold it


[/SIGPIC]

I did the filter 2 years ago after I bought it and after 20000 I had it flushed so far so good as I have almost 10000 more on it, 86 300e just turned 140000 and in the desert

Thanks, guys! They say "Advice is what you ask for when you already KNOW the answer, but wish you didn't!" I think I'll tell them to do the standard filter/fluid (PLUS torque converter...thanks!) and skip the "magic".

Frank

I admire your desire to change the fluids often, but in the case of the new "lifetime fill" transmission, I think you're going a little overboard to change it at 40,000 miles.

As far as flushing goes, you should be VERY careful in doing this to an automatic transmission. It is somewhat common for an old transmission after flushing to be incapable of moving the car. The clutch material in an old transmission can be washed away with some of these procedures requiring an entire overhaul.

I personally avoid driving cars with automatic transmissions, but I do have experience with them. The main thing to understand about them is that HEAT KILLS. The normal temp for ATF is 170 to 180 degrees F. For every ten degrees over that temp that the ATF runs, the life of the fluid is cut in half. That's quite a telling piece of information. The best thing to do is to drain and fill the trans often and if it has a replacable filter, change that often too.

I personally would NEVER do one of the flush jobs that are promoted by some shops. The purpose for most of those services is to make money for the shop. Most especially NEVER flush a transmission that has burned fluid, that is the transmission that will lose the clutch facings in the flushing process.

Good luck,

I selectively copied some information from a Newletter I get called Nutz&Bolts pertaining to transmission flushing.
I personally wouldn't use a flushing machine on a benz box, I would drain and refill, realizing that the first item listed below holds true.

1)The flush machine is only as good as the operator.

2)The flushing machine has an audible warning to prevent the machine from running the transmission dry - which can cause damage.

3) If care isn't taken dirt contamination could happen

3) Shop should be ATRA member repair shop.

Your 2000 may not have a torque converter drain plug.

Len

It is too early to change the tranny fluid. I would not touch the trans fluid till 100k miles. If I was to change the fluid, I would only change it at the dealer and no where else. They call it lifetime for a reason and I would follow their reccomendations. The trans dipstick tube actually has a locking cap on it so you dont attempt to check it. On my new CLS and SLK with the 7 speed, there is not even a dipstick tube. If the fluid is low it will trip a CE light. $269 is reasonable since the fluid alone costs about $100.

Thank you all, again. I am sworn off the idea of flushing and you have also persuaded me to wait a while before touching the transmission at all.

So now I've saved some $$ AND the risk of a problem!

Frank

I wonder if we fill the old trannies w/ this long life fluid....could we extend the change intervals?

On my ledgend there is no TC drain so I just drain the trans and fill ~ 31/2 qts along w/ the oil every 5000 miles....don't know if I am contaminating the new fluid as soon as i fill but i am scared of flushes.