Here we go again,
with the same fluid-question `popping up` ...
more than 7 years later,
and the same m46 still running okay and very reliable.
Today I lifted the car up to check the undercarriage and inspected wirings of the m46, also to attempt opening the tranny drain plug and fill plug (Murphy never sleeps so I did that in the exact opposite order
)
Despite some nightmare-ish stuck drainplug stories, in my case loosening both of them went really well... though I used a gas torch and a hammer to help break up the very tight, corroded connection (not because of an existing rounded plug issue but to prevent any bigger issues).
The tranny fluid that leaked out looked really dark.
I checked the original greenbook manual and I got surprised by what I read: for the m46 it suggests the 600-1000km ATF replacement (after first miles when car is `new`) then none(!), except topping up fluid If missing (This seems weird BTW--how often do You change your m46 fluid? In miles, or in years, share with me whatever you do with your m46)
Also, is it true that the required amount for the m46 is 2.3-2.4 Quarts (2.4x947ml)? What exact brand and what exact F type atf to use?
I found this, part of a full rebuild instruction sheet for the m46, written by IPD Volvo specialists:
``The M40 takes .8 qts of 30 wt, the M41 uses 1.7 qts of 30 wt, the M45 uses .8 qts of Type F automatic trans fluid, the M46 uses 2.4 qts of Type F and the M47 uses 1.6 quarts of Type F.``
The d24t m46 manual suggests that the correct level is right at the lower lip of the filler plug so I guess, if the correct fluid level is the filler plug itself then we can not overfill the m46 tranny even if we wanted to (car obviously should be level for this service).
Is it suggested to slightly overfill it though, as you might do the engine oil by adding 1/4 quart extra for a worn out and/or cold-climate diesel brick? I welcome your experience and happy to hear your own m46 story and m46 atf habits.
I haven`t changed the fluid in any of our m46 Volvos (never had a single issue with any of our m45 or m46 trannies, for tens of years, ever)...
so can someone verify a few m46 details please? Thanks.
Also, IPD suggests that in case of a worn (or misbehaving) manual brick tranny we could/should use 10 W 30 synthetic motor oil (Castrol etc). Anyone tried that?
I have no issues but sometimes the motor oil is much easier to find on the shelves than finding an F type ATF. Especially at /\utozone (plus there`s the covid factor, reduced staff, lines, no customer service etc).
IPD says:
``M46 & M47 Transmission Oil
Created on 2011-07-29 by IPD Staff
From the factory, automatic transmission fluid is the specified fluid for both the M46 and M47 transmissions found in the 200/700/900 models. Over the years as synchronizer rings wear and tolerances increase, we have found that changing the transmission fluid to
synthetic 10W30 motor oil makes a noticeable increase in smoothness and gear engagement. We have even noticed ‘weak’ overdrive engagement has become firmer with the new fluid. Using your clutch when shifting into overdrive can also help to reduce wear on the overdrive.``
Diesel brickers, could you let me know your best advice about the most proper fluid for my m46 transmission diesel car?
Because my m46 atf fluid level seems lower than the suggested amount, i want to get this done tomorrow and test the car right after for increased smoothness (sometimes, very rarely though, I feel the shifter not liking the 1st gear at redlights and going into reverse isnt 100percent smooth either, sometimes audible)
I appreciate good ideas, thanks for reading this long m46 thing.
OMG one more question,
According to the manual and a previous comment too, there is a `filter` or `screen` that must be flushed/cleaned/declogged. The overdrive unit must be holding some fluid too, I am sure it should be drained too by removing this cover.
Where is a filter located? I saw a nice easy-access, flat cover right under the overdrive unit, held by 6 bolts. I assume that is the filter /screen that is serving the unit.
Is there another filter anywhere in this m46 unit?
also, can I get away reusing the overdrive bottom gasket, do you think is it doable that way? Is that gasket still available somewhere? (update: yes, found it)
Hoping to get this done early morning tomorrow, possibly get the Mobile1 TD synthetic engine oil in, too. I know this car really appreciates that.
THANKS FOR THE M46 ADVICE!