1987 300TDT Transmission fluid change
 

Planning to change my tranny fluid in the next week or 2. I am looking at filters and a gasket.

* Should I go with MB filter or is Mann the OEM? I do not want to go less than Mann.

* Should I go with MB for the gasket?

* Are there any other parts I should change while I have the pan off?

* Is there anything else I can check while I have it open?

I would like to completely drain the torque converter also. I remember reading a post about having to turn the converter to get to the drain plug. How do I turn the torque converter?

Thank You!

Use a long straight slot screwdriver
 

As you look up from the bottom of the torque converter, you will see a bunch of fin like metal teeth. Use them to turn the converter until the drain is facing straight down.

I had to get the gasket from the dealer as the Wix filter kit I bought came with the wrong gasket. I Think the Mann or Beck/Arnley comes with the correct gasket.

The Wix filter worked fine. Id think about putting in a K-1 kit when it's off to stave off any 2-3 softness/flare (or correct it if you already have it)YMMV, as always.

I'm sure the Mann will be just fine

If I were you I'd buy the kit with the gasket and the filter in one packet

The condition of the transmission oil cooler lines is important. If they look a bit dodgy now is an ideal time to change them.
Not really (unless you are experiencing some problems)
Draining the fluid from the torque converter is important. If you skip this step you just dilute most of the old fluid with a little bit of new.

As described above try to find the torque converter drain plug - if you can not see it the best way to find it is to turn the crank shaft over by hand.

To do this the safest and easiest way - remove all the glow plugs (don't remove injectors as they will need new heat shields on refitting) - 27mm socket on big nut on the end of the crankshaft - turn crank in a clockwise direction (when standing in front of the engine looking straight at it).

Before you start draining fluid get a large drip tray and a decent measuring jug.

I recommend you measure the old oil very carefully as you remove it from the system - especially if you replace the transmission cooler lines

Remove the transmission oil pan and collect and measure that fluid too

Replace filter (after reading the concerns of Mercedes about lint free cloths! - see owner's manual / maintenance manual)

Check to see if transmission pan is still straight - look for damage

Fit new transmission pan gasket - do not over tighten the screws that hold it in place

Replace with clean dexron III fluid (via dipstick tube) by measuring out exactly the same amount of fluid you put in (clean your measuring cup before you start!)

Don't forget to replace your glow plugs before you try to start your engine!

603 glow plugs aren't easy to replace. Not something I'd bother with for a tranny fluid change. It's not difficult to turn a 603 crank with enough leverage. Make sure to turn in the normal direction of rotation only - I use a ratchet. Or bump the starter.

If you're going to refill based on what you drain, make sure the level is within spec before you drain. You know to fill slowly with the engine running after the first 3-4 quarts, right?

Sixto
MB-less

Thanks Sixto

I didn't realise about the glow plugs on the OM603 - make sure the accelerator linkage is in the stop position if you crank by hand and the cylinders have compression.

The maintenance manual says to fill in 4 litres and then run the engine - that's close to a US quart isn't it?

Here's a link to the maintenance manual on startekinfo

http://www.startekinfo.com/StarTek/outside/11832/Resources/201Create/PDF/80001a.pdf

(takes some time to down load)

I would only use Mann filters or OE from the dealer. Other brands have a nasty habit of collapsing which causes all sorts of shifting problems.

The torque spec on the pan bolts is REALLY low, like 7 Nm. Overtighten, and you may warp the pan which will then leak.

I've always re-filled with Mobil 1 synthetic ATF, and I highly recommend it. When I bought my '87 300TD, it had about 270k miles, and shifting was very inconsistent. After about 10k miles with the M1 and new filter, all was much much better. I know others who have had the same results with the Febi fluid, so perhaps simply fresh fluid and filter (and driving time) is all that is really required.

You can also use a 1 & 1/16 inch socket to turn the crank pulley bolt. I use a deep socket plus a short extension on a breaker bar and it fits in there perfectly. Make sure the engine is compeltely cold, you can turn it slowly. Very unlikely it's going to fire up. I guess a rachet would be safer? haha I don't know. Be careful.

Trying to turn it by the bell housing with a giant flat screwdriver is extremely frustrating. Just use the crank bolt. So much easier.

Make sure you fill 4L and then start it up and let the fluid uptake into the trans, put it in each gear for a few seconds. I know my car said it takes about 7L or something but in the end it only took about 6 I think. You have to fill slowly. On mine just 1/4L too much will put it WAY over the full line. If you over fill it just go buy a hand pump from Walmart and suck some out. So add the fluid a little at a time and avoid that problem.

I used the Meyle kit. It worked fine. The seal was a bit tight and didn't like staying in place but I got it seated and made sure it was in there as I tightened it down. Just hand snug with a 1/4 inch socket.

Thank You All for your input! My plan is to purchase:

1 Mann Transmission Filter (126-277-02-95-M63)
1 MB Transmission Pan Gasket (126-271-11-80-MBZ)
7L of Mobil 1 Synthetic ATF

Whilst I am in and around the tranny should I look to change the shifter bushings (1987 Mercedes-Benz 300TD Base Wagon - Shift Linkage - Page 1

Is there anything else I should replace while I have it open?

Thank You Again!!!

I'm not sure what your car calls for. Mine just calls for "ATF" and I used Castrol Dexron III for domestic vehicles from Walmart. I've used it in a few vehicles and it works awesome. Shifts nice and smooth.

Those shift bushings can be a real pain to replace. I had to remove the lever on the transmisison to get one of them pressed into place.

Mercedes Suorce sells a tool for $80 to press them in. I used a couple of big washers, and a bolt and some smaller washers setup so I could press them into place after lubing them up with some silicone grease. You'll never get them in with your bare hands, that's for sure.

Torque converter drain plug, gasket install tip
 

Here's a photo of the drain plug. The plug takes a 5mm Allen wrench. The flywheel teeth are also identified. One of tricks of the trade is to suction out trans fluid through the dipstick tube. You won't get it all, & this won't drain the T/C, but it will reduce the amount of fluid that hits the floor, your face, your clothes, etc when you drop the pan. Definitely inspect the cooler lines, & replace if they're questionable. Another gasket trick is to use flat dental floss looped through the pan bolt holes to tie the pan gasket to the pan. (Keep the knot outboard of the sealing surface. I'm not a big fan of sealant/rtv/glue on pan gaskets. If time permits, I press the gasket flat using several old Chiltons stacked on a sandwich made of the gasket in between two sheets of plywood. Torque wrench is a must for pan bolts. Add that fluid slowly, or it will overflow. After the fourth quart/liter, start the engine & top off slowly.

Good luck!

Oh dental floss! Pearls! Pearls of wisdom!

I also highly recommend spray washing the bottom of the car first and sweeping the garage floor. You don't want sand/dirt getting into anything.

When you loosen the dipstick tube nut it all mostly drains out. what's left in the pan is easy to handle.

Sorry for refreshing an old thread. I am finally going to get to this next weekend. I would like to replace the transmission cooler lines.

Is it ok to go with Tructec for the lines. I would much rather go with MB for the parts. Alas, Pelican only has 1 genuine MB hose of the 2 hoses I will need. That one is 3 times the price of the others. (1987 Mercedes-Benz 300TD Base Wagon - Automatic Transmission - Page 3) Is it worth the extra for a hose?

Thank You for sharing your wisdom and experience!

A forum member was telling me last week about a Tructec fuel supply hose that cracked within 2 years of purchase. Filled up the tank, next day tank is empty. That hose isn't under pressure like a tranny cooler hose is. You can change the fluid now and replace the hose in the future. You'll lose, what, a cup of fluid max?

Sixto
MB-less

On a major assembly like a transmission, where failure will lead to destruction of the major assembly, I would only use MB parts purchased from a dealer. I'm very frugal with many things, but in today's made-in-China world, I view all rubber components with a jaundiced eye, and tend toward only purchasing from a dealership.