xxaarraa

Folks,

About to do a tranny fluid replacement in my 06 C55 (40k miles). I am following this thread closely as my guide:

http://www.benzworld.org/forums/w210...ion-fluid.html

It's pretty self-explanatory, however, it is for a different car and not the C55. My C55-specific questions are:

• Exactly how much tranny fluid (Quarts/Liters) does the C55 tranny hold?
• I purchased the tranny dipstick to check fluid level. However, I don't have a STAR system or a temperature gauge. I am thinking of filling, starting up the car and idling for a few minutes, taking the "25C" measurement, taking a short drive, and then taking the "80C" measurement. I know it's approximate, but I don't see a reason that should not work, especially if quantity of fluid that went in is roughly the same as quantity that drained as well as in the ballpark of overall capacity? Can anyone confirm if this approach is reasonable?

Only opinions on the topic please. "Dont flush your tranny" or "take to dealer" isn't going to help anyone. Thanks a lot in advance,

Saaboteur

The owner's manual lists transmission fluid capacity as 8.7L. However, I believe that includes the fluid in the torque converter. The last time I flushed the 722.6 trans was in my C43, and for the life of me I could not figure out where to drain the converter. Turns out the drain for the converter was hidden by the exhaust downpipe. Not sure if it's the same on the C55, I haven't gone in there yet and actually am planning on flushing it myself too.

If you have the time, why not just grab an infrared thermometer? They're quite readily available for maybe $20-40. I used that before, per the thread you linked to. I grabbed mine from Canadian Tire, but you probably don't have one of those nearby, unless you're Canadian like me. But I'm sure you can get them at most hardware stores.

If not, I think you need more than a short drive, probably at least 15-20km, not just around the block.

Or just take it to the dealer....

xxaarraa

Thanks for the suggestion on IR thermometer. I found quite a few on Amazon for $20-40.

http://www.amazon.com/HDE-Temperatur...9930832&sr=8-1

http://www.amazon.com/General-Tools-...9930832&sr=8-7

Where do I aim it to get an accurate reading? Inside the dipstick or under the car at the oil pan? Also, what are some other uses for an IR thermometer? I hate buying one-time use tools, but might bite the bullet if absolutely necessary.

Also, I bought 6 quarts of tranny fluid. I am not too concerned about not getting the fluid in the torque converter out. I think that 6 quarts of new fluid is better than 0 quarts (and good enough). If it takes more than 6 quarts, I may have to run to the stealer to get another quart.

Saaboteur

I aimed the thermometer at the pan - that's where the fluid is. It's a bit of a pain to crawl underneath to aim it, but that's the best place to aim, IMO.

Other uses for the thermometer....a buddy has one in his kitchen, for cooking purposes. Not that useful for, say, a roast, but it'll work for surface temps I guess. If you ever roll fenders on your car (to clear wider rubber, or more aggressive offset wheels) you can use the thermometer to check the temperature of the fender (when heating it up with a heat gun). The idea is that the paint won't crack when heated up. If you play hockey and use shafts with replaceable blades, the heat gun is used to heat up the shaft to allow the blades to be fitted, both by heat expansion and melting the glue. If you're lazy and don't want to get out the hairdryer, you can use the heatgun for that too. I lent my heatgun to my cousin for the purpose of applying anti moisture film to his windows in the winter, forgot that he had it, and when I went to his place I found that he was using it to dry his hair. Promptly labelled him a lew-zer and grabbed my heat gun back.

xxaarraa

Saboteur, i ordered an ir thermometer man. I cant see myself ever using it again from your description lol but figured at 20 bucks it was worth a clean job.

Thanks for your help, will keep everyone posted on how the job goes.

GTibunny8v

Transmission services are simple. You really dont need a SDS or ir thermometer. Drain the fluid in the pan, remove the pan and replace the filter. Reinstall the pan with all 6 mounts snug but not tight, make sure the gasket is seated correctly.Tighten the screws to 8nm. Add 3.2 qts of fluid, let it sit for 15 min for the fluid to get out of the dipstick tube. Start the car and check the level. It should be in between the lower markings, if not add fluid till it is. I used to check them hot but after the first 20 or so I stopped doing it. They were always at the proper level when hot. I've done hundreds of trans services and never had a single problem.

fleishman

FYI
I have an infrared thermometer and tried to use it to check the temp at the bottom of the pan with little success. Even after a 20mi drive the bottom of the pan only measured 57C. I shot the temp of the oil on the end of the dip stick and got a nice 79C. I do live in maine and it was 35F outside, maybe the bottom of the pan transfers heat too quickly to get an accurate temp in cold weather.

After warming the car at idle the level was at the bottom of the 80C dipstick mark and after the drive it was close to the top mark.

91RS

You'll probably only need 4-5 qts. doing the pan service. The C55 doesn't have a torque converter drain so no need to worry about that. That guide is right on the money so as long as you follow it, you'll be fine.

xxaarraa

Hey guys,

Just finished the job today. I drained only 3.85 liters - oil was pretty burned and there was a lot of sludge on the pan magnet. Accounting for clingage and spillage, I put 4 liters back in. When I put the dipstick in for a 25C measurement, oil was way off the mark (higher than even the 80C max). I went for a 20 mile drive and tried again and still way higher than dipstick mark.

Since I put in exactly what I drained, I am not worried. I am assuming either the dipstick was for the wrong model or some other user error in getting a reading.

loudandheard

Where did you get the dipstick? I got mine on eBay and I tried to keep mine to the level of the dipstick. I might do it again for piece of mind. How is it driving?

xxaarraa

I got it from autohausaz. It's driving fine so far.

gnma

I've been doing lots of reading on this topic as I may attempt this myself. I have three questions:

I know it's stated above, but to be sure, does our C55 have a TC drain bolt?

Does one have to drop the pan in order to change the bushing that houses the o-rings that fail and cause a leak?

The c55 uses the 722.6 transmission. Is this right?

Tks much!

JonMBZ

I think with the torque converter and valve body you have over 10 quarts in the system. I wouldn't want that sludge mixed with the new oil. Even if it doesn't have a drain it doesn't mean it shouldn't be changed. Not sure what dip stick you have, but with the OEM one there are two different levels to check it with. One is when it is hot and the other when it's cold.

Saaboteur

722.6 trains for sure, but if memory serves, there isn't a torque converter drain unfortunately. There was one on my C43 (also a 722.6) but to get at it, one of the exhaust down pipes had to be removed as it blocked exactly the spot to access the converter drain bolt.

Re: bushings that cause leaks, do you mean the ones on the large electrical connector that goes into the trans? That one is actually above the pan too, but it is a bit easier to get at with the pan off. Caveat on my comments - they were from working on my C43, I never did the connector on my C55 just my C43. I think it was significantly easier doing it with the car on a hoist.

JonMBZ

The connector was done via recall on my car