Its been 30k since I had it drained, new filter and filled at the mercedes dealer Thinking I will do it myself this time and just use the drain plug rather than dropping the pan (unless the fluid that comes out looks nasty). If I just drain, how many quarts of the Merc fluid should I have on hand?

 

About 4. But that's only about half the fluid in the transmission. What I did was drain, fill, run it, and repeat 2 more times, which changes about 90% of the fluid. For that you need 12 quarts.

 

If you are doing a full drain, you will need 7.5 LITERS. Unfortunately, the XJR 722.6 tranny does not have a drain plug in the torque converter. My Mercedes C280 722.6 fortunately did have a drain plug in the torque converter and it was 7.5L. If you drain from the pan plug only, you will miss about 1/2 liter, because the top of the plug mount is about 1/2" higher that the bottom of the pan and that fluid below the plug mount will not drain. It is really easy to just undo the six bolts holding the pan, after draining the pan. Use only the Mercedes ATF 134 fluid, even though it costs about $23/liter. Otherwise you may get slipping after a few thousand miles, and by then the damage may already have been done.

Here is a thought, the next time you have to pull out the tranny, consider replacing the torque converter with another one with a drain plug. And don't forget to buy a transmission dipstick. 722.6 trannys run best when at the full mark.

 

Thanks Guys, and I don't plan on taking the tranny out ever. That is why I'm changing the fluid.

 

AJ26 XJR has drain plug. Copied from MB forum: "All drain plugs were deleted by 30-09-99. "

 

good afternoon


I have 2 XJR, one BRG one black, both had the same tranny issue with fault code,slip gear. here is what you need to get and done. issue was fixed on both cars so I have 100% confirmation that could be fixed. DONT waste money for just changing the ATF.


For Mercedes Transmission Conductor Plate Connector Filter Gasket 722 6 | eBay


Shell ATF 134 Mercedes Benz Transmission Fluid 236 14 236 12 6 Quarts 5080660 | eBay

 

I have had zero tranny issues with my 03, just fluid changes every 30k or so no need to replace parts for the sake of it. And my 03 has a drain plug on it. Just verified yesterday.

 

The conductor plates are known to fail .... but the much more common problem causing the same issue is the connector. The OE part is available for $12.00

TreVorTasmin - the drain is not the drain pan. They all have the drain pan -- the early version MB transmissions had a drain on the T converter.

 

I thought it odd that an 03 had a pan with a plug (don't know why previous owner would've replaced the pan prior to 60k) but find it even odder that in a tranny that had "lifetime fluid" they would have put a drain plug in either and then as they realized the error of their lifetime ways they stopped. So what is this problem you two speak of, my tranny has been the best auto I've ever had over 110k, smooth shifts, idiot proof tcu etc. Only issue it ever has is those random initial heavy shifts out of 1st after running slow (like in a parking lot) when cold. The XK8 tranny not so much, in fact I would much rather have an 80s GM tranny in there then the ZF crap.

 

The R has the MB box -- the non SC cars the ZF. The MB box will use 1st if in sport.

When the MB electronic transmission came out in the mid 90's. Two things were in mind -- the transmission required what was then a new and not widely available fluid and the normal life of a car at that time was under 150k.

Knowing that many owners would use the wrong fluid and the vast majority of the cars would die with functioning transmission -- they called them Lifetime.

I have had many cars with the MB box and the only one I touched was the one needing a new connector.

 

Never had a car that didn't go well past 150k so I can't comprehend that at all.

As for the tranny, I like to tow my camper at speeds near the "ton" so I've always looked at tranny fluid as a much cheaper alternative to a transmission rebuild.

 

How old are you? How old was your first car.

The transmission were designed in the very early 90's for later 90's introduction. Cars did not last as long -- both mechanically and body (rust) Paint.

Even MB .. who had the largest segment of long term owners had very very original owners past 150k and 7 years ... that's lifetime in the auto business 1998.

 

Old enough but young enough to not have owned any cars from the 70s. I do one thing that 98% of the population doesn't. I take care of my cars and believe strongly in preventive maint and care. I don't even have a single electrical issue with my TVR (at the moment that is). Only tranny issues I've ever had were on the Subie SVX and XK8. Bought both knowing the tranny was the weak point and bought priced as such. Both needed a rebuild before they hit 100k.

 

I think just like the exact purpose for the existence of this forum. We are sharing out the experience and knowledge of the same car we all love.


no one is lecturing no one else here and at the end of the day we all make the final decision of the car we own.


I did what I did was because it has fixed my issues of both XJRs and proven permanent resolution for a total cost around 450 bucks(parts and labor) and 722.6 tranny has tendency to fail and the plate and connector will get wet and slip. if not now, one day(actually soon considering the age of X308)


I can not think of any reasons why not doing it (at least for me)

 

I forgot to mention that the first fluid change, I removed the pan and fitted a new gasket and filter. The next 2 times, I just extracted via the dipstick tube. You get 3 quarts out that way, so I actually used about 10 - 4 for the drain, 3 each for the two flushes via the dipstick.

 

The OE MB transmission filter -- Has a small fleece at the pick up and and had what I would call a screen inside. (last I dissected). I was sad to see that the latest Mann aftermarket, while still metal was made in China. The electrical connector can be a huge problem -- On the MB's the fluid can actually travel up the harness and flood the control inside the engine compartment. It was a quantum leap in transmission technology -- especially considering how bad MB transmissions (auto) were in the beginning.

The first set of fleet cars that all made it to 200k were our 2000 Lexus ES 300's -- some of my employees are still driving them with 300k +.

 

Oh didn't think you were lecturing and thanks for the input. I just liken it to all the other parts on a 100k XJR that are past their prime. Once I get a code or experience any issues it would get replaced but until then I'll continue on replacing fluid. LOL I actually never read about the plate or connector issue prior to your post so it is great food for thought as of course like with any car there are some fairly common "faults" or weaknesses.

 

Those poor souls, a week behind the pleather steering wheel of a Lexus I'd be buying a bus pass.