torque converter ATF
 

I just had my 84 300TD ATF changed. I gave my indy 7 quarts to replace the ATF. But his asst. gave me back three of the ATF bottles he did not use. It did not occur to me at that time but now I realized he may not have changed the ATF in the torque converter. Is this a correct assumption? I used to use up all 7 qts. every ATF change. Is there any harm if I change the ATF in the torque converter 30k from now (next ATF change) The car has orig tranny with 302k on it.

thanks a lot guys! nice change on the website. keep up the good work.

Asti-1984 300TD -302K and going
Ruby-1999ML 430 -65k :)

That sounds like exactly what he did. Too much trouble to change the fluid in the T/C. :mad:

Who can say, with any certainty, what three old quarts of fluid in the system will do. Some people go 90K and don't change their fluid. Some transmissions live with this, some don't.

My best comment is that you are four quarts better off than you were prior to the oil change. :D

I'm curious to know how much you're saving by waiting 30K miles.

One alternative is to replace the other 3 quarts now. Assuming the tranny holds 7 quarts, the first change got you to 57% clean fluid. Draining and refilling the torque converter will get you to about 75% clean fluid. If you don't do it yourself, it should be a cheaper job since you don't need to replace the filter. Another alternative is to take the car to a place that does a tranny fluid flush with the engine running. They hook up a pump through the tranny cooler lines. I don't know if MB lines are compatible with those machines.

Sixto
95 S420
87 300SDL

Take it back the the shop & explain to the manager or owner (if needed) what happened. Tell them you understand the tech probably didn't realize the TC has a drain plug of it's own. Give them back the 3 qts & tell them to do a new oil change w/ 7 clean qts. Don't just drain out 3 & dump in 3.

If shown a little understanding a reputable shop will usually right a wrong.

Good Luck.

I am with cmichalik on this.... this is the only way to do it correctly.... and it brings the assistant's lack of knowledge gently to the supervisors of the shop.. so maybe it won't keep happening to other people also.....and it gets you ALL clean fluid ... which was the purpose of taking him the 7 quarts in the first place....

but how do you get to that damn TC plug? I try bumping the starter but it never seems to rotate into view. Whats the easiest way to turn the motor? It didn't seem to have enough clearance at the front pulley to get a wrench in.

"Torque converter? Nah, you never change the fluid in the torque converter. Hell, I've been in this business for 20 years and we've never changed the fluid in the torque converter in all the years I've been working. Hell, there is no way to get the fluid out of the torque converter on American cars. That drain plug that you are talking about, hell, nobody ever takes that out........................" :mad:

Yep. MBs are the only cars I know with a drain plug on the torque converter....

Brian,

I will never bring my car to your shop for a ATF change. I will take it to a place that is more competent or do it myself.

It takes less than a minute to R&R the TC plug and if you remove it first, all the ATF will run out while you service the transmission.

Would you only drain half the oil from the engine on an engine oil change? I bet you don't drain the engine oil cooler either.

Some American manufactures are too cheap to put a drain plug in the transmission pan too.

P E H

I haven't been to the shop at all. I was just writing the above tongue in cheek, PEH. But, you are right. There is no good reason for not changing the t/c fluid if the mechanic knows there is a drain plug for it.

BTW, you are correct in that I have not changed the oil in the cooler in the past. Do they normally have a drain plug or do you remove the lower hose? Probably a damn good idea to do it if its not too much trouble.

Odie,

You can use a screwdriver to turn the TC. Just put it in one of the holes near the drian plug and lever the TC plug into position.

But the recommended way it to turn the engine is by the crankshaft bolt. You need a ratchet and a 27 mm or 1 1/16 socket. A deep socket should work alone but a regular socket may need a short extension bar. I Never have any problem doing it this way.

P E H

thanks PEH...thats actually my project for tomorrow. I'll try to find a 27mm socket or try the screwdriver trick.

Brian,

Just loosen the lower fitting (large nut) on the oil cooler. If you don't remove the fitting, there is no chance of cross-threading it.

The oil will drip out slowly, but since when I change the oil I always let the car sit overnight with pan plug removed and cooler fitting loose, its no problem to me.

P E H

odie,

You also need a 5 or 6 mm allen wrench to remove the plug. The plug may be difficult to remove the first time. I had to heat mine to remove it the first time, it was really in tight.

P E H

Odie,

If you have to buy a 27 mm or 1 1/16 inch socket, buy the deep socket because it also works to remove the injectors should that ever be necessary.

P E H

Thanks PEH. I do the same thing with regard to the overnight drain. I'll pull that lower hose next time and let it drain as well.

Don't try pulling the oil cooler hose off of the SDL! You could ruin the threads on the oil cooler! I don't think you get much more oil by draining the cooler, I get about 8 quarts by just pulling the plug. If it was important to drain MB would have put a plug on the cooler.

?? I replaced the SDL tranny cooler hoses last year and it went okay. I had to take care to turn the hose nut and not the fixed nut but it went smoothly.

If this is in reference to my post, the point is not to flush the cooler but the flush the tranny system through the cooler lines. The question is - is there a thermostat that causes ATF to bypass the cooler rendering this method of flushing not completely effective.

Here's some info - http://www.gadgetonline.com/TransFlush.htm

Sixto
95 S420
87 300SDL

Sorry Sixto, unless I miss read P.E.Haiges was recomending to disconect the engine oil cooler hose when draining the engine oil? :confused:

Hatterasguy,

Yes, I was talking about the engine oil cooler. If you noticed, I said to only loosen the nut on the oil cooler connection, not remove it and let it drip overnight to get all the oil out of the cooler.

P E H

PEH,

What's the big deal with removing the hose? Once you break it loose, the major problem is behind you. What is the big concern about cross threading?

On the subject of tranny fluid changes...I have a filter/seal kit in my shop waiting for me to do mine. Not sure what TYPE of fluid to buy though (Notice I did not say BRAND). My MB manual only says to use MB brand fluid. Looking at the tranny fluid shelves in the stores there are several different types of fluid for different vehicles but they don't specify for MB's.

p.s. I will drain TC.

I am a beleiver in synthetic when you have to tow or haul a load. I suppose it could be overkill in a car. It does work nice in the cold weather, though. I may change to synthetic in my 300D hoping it will help the shifting (usually rock hard) - probably not based on all I read about adjusting these things. Both Mobil and Amsoil make a good synthetic tranny fluid. They are expensive, I think about $5 - $6/qt.
The owners manual for my '79 just says ATF if I remember correctly.

Any dexron 3 will work fine. I buy the cheap stuff because my trans is starting to slip.

To add, I use a mirror propped in the right place to show me that the plug is lined up.

Brian,

Loosening only and not removing the lower fitting on the engine oil cooler eliminates the possibilty of cross threading the fittings when reconnecting with no detrimential effects. The flow rate of the draining oil is reduced but since I always let the oil drain overnight, the lower flow rate is of no consequence.

I change my oil on even 10,000 increments and I am usually away from home when its time to change the oil. So I want to eliminate any chance of something going wrong. Not removing the oil cooler fitting is one simple way of eliminating a possible error. Another reason: those coolers are very expensive to replace if you screw one up.

P E H

Engine oil cooler draining--doesn't the oil drain out of the cooler when you remove your drain pan plug? i would think it would unless there is a check valve i don't know about... :confused:

cheers,

bill

Bill M,

NO, the oil in the cooler probably has too much plumbing to go thru to drain by itself. The output side is connected to the engine oiling system and the input goes to the oil filter and a thermostat bypass.

Anyway, everytime I loosen the coupling to the engine oil cooler, black oil comes out of it. I like to get out as much used oil as I can.

P E H

P E H--thanks and next time I will loosen 'em up.

And I know what you all mean about getting the threads crossed on the cooler. I had a td once that needed one and was lucky to find a good one in the local junkyard. Got it home and proceded to get the threads crossed. Easy to do on aluminum. Needless to say when my brand new cooler arrived I was very careful. Funny how money will make you change your ways in a hurry!! :)

Cheers,

Bill

screw the 27mm nut on the crank. too hard to access. :mad:

I used a 22mm? wrench on the PS pump pulley nut. Works like a champ for turning the motor over! :D

So easy and no getting greasy under the car.

The screwdriver method, applied with care, worked great for my T/C.