should I change my tranny filter?

My auto transmission was replaced with a MB rebuilt at around 200k. I now have 260k. To my knowledge the filter has not been replaced. I'm not suffering any tranny problems and the fluid looks nice and red and clear on the dipstick. Should I leave it alone or should I just change the fluid and leave the filter alone?

Just wanting to perform some preventive maintenance but not wanting to get too uptight about it!

[lrg]

I believe the factory spec is for a fluid and filter change every 30,000 miles. I'd do it now and every 30,000 from now on.

Don't forget the torque converter too! Spin it with a flathead screwdriver until you see the drain screw. I drive my car hard and often so I change fluid and filter every 20k. It's cheap insurance.

[fredjj]

Ditto what lrg and turbodiesel stated. It's a messy job and turning the tourque converter can be a pain. But when you get it done it's a major feel good. I changed the ATF (to Mobil1 ATF) this past weekend on my new to me 81 SD.

[gsxr]

Yes, change it every 30k for normal use, or 15k for "severe service". Change the filter and fluid in the pan AND torque converter. It's such a nasty, messy job that I usually pay the dealer to do it (once every 2-3 years, which helps me stomach the cost... ~$125 or so.) If you have a lift or a pit it would be MUCH easier. I did this once at home with floor jacks and swore I'd never do it again w/o a lift.

My cars usually start acting up at 20-25k, shifting firm when cold, etc and the fluid change has always cured that. Next change I'm going to Mobil-1 ATF, which many others have said makes the tranny shift more consistently regardless of temperature...


Regards,

[Wasuchi]

I changed mine about two months ago. It looked nice and clean on the dipstick, what came out of the pan wasn't too bad.... what came out of the torque converter wasn't clean though, it was almost brown. So.... just because the fluid looks good doesn't mean it is. It isn't that hard a job..... just make sure you don't overtighten the pan bolts if you do it yourself.

[wheelguru]

My manual for the '78 says do it every 65000 - you would be due according to that. I did it last week and it was not so messy, I thought it was fairly easy. made a difference in shifting for my car. If you do it yourself you are going to want the car up nice and high on some jackstands - if it is not high enough to get under there easily I can see where it would be a major pain in the butt.

[lrg]

gsxr (and others),
I have just completed 5,000 miles in my W123 after switching to synthetic ATF. At first the change was minor and I was a bit disappointed that my shifts weren't noticably smoother. Today I was driving around and was struck by the fact that the tranny has gotten much smoother. I still get a little clunk when it goes into gear stone cold but otherwise it's really improved. It obviously won't correct vacuum modulator and/or Bowdin cable adjustment problems but if everything is basically sound it really helps. The synthetic ATF must take a while to clean up the tranny but when it does you'll notice the difference. Now I'm wondering if I should do an early change to drain all the newly freed up gunk out. Moral of the story is you'll be very happy you switched to synthetic but don't be put off if you don't notice an immediate benefit.

LRG

I say get it changed, but get it done at a dealer or a transmission shop that can work on a Mercedes. They can tell you if you have any transmission problems that need to be adressed, you also avoid the messy job at hand.

Was sent a filter and gasket kit by a parts house. Got under the car and eyed it up, it didn't look right. Sure enough, I double checked with MB Classic and they sent me the wrong part!

Can you imagine me draining the fluid and taking everything off on our only vehicle and then having the wrong gasket and filter?

At any rate, I will definitely be doing this myself with my friend Seth to lend an extra pair of hands. No way am I going to pay a dealer.

I changed my differential oil last night. Used a breaker bar and was able to get both plugs out just fine. Replaced with 75W90 Synthetic. Yup, the old stuff definitely smelled burnt, which I hear is normal. Good feeling to get it done, though.
-shawn

[Wasuchi]

Gear oil always smells bad..... like I posted earlier, don't get the bolts too tight on the tranny pan... lots of people have and it causes it to leak. Might do a search on it to see all the little things to watch out for too. Good luck.

[380SEGUY]

Hello all

One of the newest and in my opinion best methods for servicing transmissions is the "power flush". There are several different machines out there on the market that acomplish this task, but my personal favorite is the BG PF5 machine.

Some of the other units use an electric pump to move the fluid through the tranny, this is fine if you have a trans that uses fairly high line pressure, but what if your trans is designed for 30 PSI line pressure and the machines pump develops 45-60 PSI?

The BG machine is my favorite for a couple of reasons:

1. it runs on the transmissions own front pump, so no danger of blowing out seals with too much fluid pressure

2. It cycles about 16.5 quarts of tranny fluid through the transmission, on most MB transmissions this is close to double the fluid capacity.

The reason this method is prefered is that as trans. fluid ages it oxidizes and those oxidants cling to metal parts, when you do a traditional fluid change even with the MB drain plug on the converter, you still leave about 2 quarts of old fluid in the clutch packs, servos, valve body, etc. The old fluid with fresh detergents then goes in and washes all of this gunk away and allows it to cycle around and get to seals and clutches.

The power flush get all of the old fluid out without even dropping the pan! The machine hooks up to the trans. cooler line!

One thing to do though is replace the filter along with a power flush about every other time, as MB filters are paper element types they will break down over time.

Hope this helps