1xsculler

Is there a dipstick kit for the 722.9 tranny in a, 2012 gl450?

What I really want to know is if my recently acquired car has ever has a transmission fluid change (86k car). It seems as though I could, momentarily, open the drain plug to let a very small amount of fluid escape, re-tighten the plug, and inspect the fluid. If it is red I could assume the transmission has been serviced, right?

It looks like there is a dipstick kit for a 722.9 tranny on Amazon but it's for a Sprinter and the tranny must have a fill tube. Is there a fill tube on the 722.9 tranny on a 2012 GL450?

TX07GL450

Unfortunately no
I wish
but welcome to future, sadly !

1xsculler

How about checking the color of the fluid by letting just a few drops out of the pan drain plug? One would have to be careful and quick.

TX07GL450

Theoretically yes.
but the color might not actually indicate if it has been changed or not. It might still be red or reddish.
If I would get under it and open the drain, I would probably do it all.
I last replaced it at MB dealer using their $150 off $300+ service about 16K miles ago. These coupons become randomly available at slick deals.

1xsculler

Thank you!

eric_in_sd

The fluid condition is kinda sorta maybe a moot point. The consensus I've heard from EXPERTS ON TEH INTERNETS is to do a fluid "change" every 30k miles. Drop the pan, change the filter, inspect the fluid. This replaces about half the fluid with new. So if it's been more than 30k miles, you ought to do it in any event.

If you go to an indy, or maybe a friendly dealer, you can get them to reset the programming and extract info from Star on the clutch wear. Or so I am told; I have not done this personally, but am planning to shortly.

1xsculler

So, I did let about a dozen drops of fluid drop out of the loosened tranny drain plug and the fluid had not the slightest tinge of red to it. It was sort of dark grey which makes me think it's time to change the fluid/filter in the tranny and in the TC. Based on the grey color I can't imagine it ever was red. It appeared to be very clean. Are there fluids for a 2012, 722.904 that are not red when new?

eric_in_sd

It was originally blue. 236.15 spec.

Regardless of what the fluid looks like, if you haven't had it changed in the last 30k, you should do so.

There is an argument for only doing the change, not a full flush, when the fluid is old or is of unknown condition. That is, the shock of new fluid throughout will suddenly dislodge a bunch of debris or something.

TX07GL450

If your tranny is not having any problems with shifting, just drain and refill is the best thing to do.
You can do it again in 30K and so forth.
As eric said, the general consensus is not do full flushes due to one or another reason, especially when last change time is unknown.

MBENZTECH

I keep reading to do a transmission service at 30k miles. The interval set by Mercedes is 40k miles for the 722.6 and 722.9(04-11). 722.9 from 2012 and up they changed it to 70k miles. I would still do it at 40k as I think this is the perfect interval. At my shop, I recommend it at every 40.

eric_in_sd

As with engine oil, the fluid continuously changes over time. Therefore there is no one point at which the service is late. It is a matter of weighing the cost of the services (which add up) against the amount by which the services extend the life of the transmission.

Roughly: A fluid & filter change service costs 1/20 of a rebuilt transmission. If a change extends the life by 5K miles (assuming an unserviced transmission only makes it to 100K), then it's worth it. Add a second service and the extension is probably less. You can probably get 200k miles out of a transmission, but if you had to service it every 10k miles, it would have cost you the same to get a new transmission at 100k and never service it.

I am suspicious of the 70k number; I have the feeling MB doesn't want the warranty claims from techs dropping the pan and seeing metal shavings. They'd rather just box the whole thing up and sell them a new transmission at 100k.

Anywhere in the middle is probably fine. I asked a transmission guy at Benzworld, and after some hesitation (he knew there was no one hard number) he blurted "30k!" I wouldn't go 50, and I wouldn't go 20. 40 sounds like a great recommendation. 30 if people have the money and don't mind spending it.


P.S. Engine oil actually increases "lubricity" in the first few thousand miles. So very frequent oil changes are actually worse than ones that go a bit longer. I suppose the same is true for tranny fluid.

kombifan

40k is a good number