Sorry about your folks' problems with the M47 II.

I've owned four of the M46 and now three of the M47. All are the M47 II.

Each time I investigated the M47 transmission fluid, teh fluid was not ever the honey colored, apparently never aging Volvo factory installed Volvo Fluid #1161645 that vvpete (brickboard and turbobricks) strongly recommends we keep in our M47 (and other) Volvo manual transmissions.

According to vvpete (you'll have to search brickboard and the i-net using "M47" and "Volvo" and "1161645" in your search expression), the Volvo 200 series and 700 series auto owner manuals that came in the glove-box of your Volvo was wrong indicating you use Ford automatic transmission fluid specification "Type F" or "Type G". (I think "Type G" is like "Type F" with no fiction modifiers and resists shear through the hydrostatic friction, yet a heavier viscosity or maybe additives of another sort.)

Those of you with vintage 200 and 700 series Volvo factory green service manuals in the M47 manual transmission era may see Ford "Type F" as the specified fluid. I dunno.

vvpete seems to better know the history of the Volvo Fluid #1161645 than anyone. Please find his articles. It all appears a broken history. Yet vvpete asserts that at the factory, your Volvo 240 M47 transmission was filled with Volvo Fluid #1161645.

So, many Volvo 200 and 700 series owners with the later M45/M46 (the nearly needle bearing version, I guess, I'm unsure, all my manuals are packed up and five miles away now.) and the entire M47 series, may have had a manual transmission fluid replacement at your Valvoline or Penzoil or auto service center lube change store. Perhaps those owners that patronized the stealerships also greeted those M47 transmissions with the Ford "Type F" automatic transmission fluid.

Some mineral "Type F" offerings would break down. Some may have compounds that play havoc with the synchros using bronze in the alloys. As the "Type F" breaks down, those bearings may suffer.

Other owners may have filled the M47 with the generic auto transmission fluid. There is no such thing as universal lubricating fluid for an application.

For example, the Haynes 240 manual in all iterations (or maybe the 1980s and onward editions) incorrectly calls out only Dexron III for the power steering system on all Volvo 240s. If you do that, and I did once, you'll find your power steering system come to utter ruin and quickly.

The M47 is sort of a fuss budget, proper lubricant aside. You cannot use the M47 with an engine producing more than 150 or 170 horsepower and corresponding torque increase. Why all turbo 700 and 200 models used the M46 or auto transmission. In one article on a Volvo board that I forget, someone wrote the M47 has "glass gears". There are many M47 II models and some may be of a stronger design for use on turbo engines. I'm unsure.

You also do not want to force the shifts. Shift gently. Some may find you can shift gently into first when approaching a stop. Some find it better to stop the Volvo completely at a stop sign or light, and then shift into first gear.

If the M47 has suffered incorrect fluid, yet gentle use, don't lose heart, yet verify the fluid condition and replace.

As vvpete stated repeatedly:
- Use only Volvo Fluid #1161645
- Use the Redline MTL the Redline website specifies as the only second choice

Yet replace the Redline fluid every 30k to 50k depnding on driving conditions.

Always use the overfill method with the Volvo manual transmissions when filling with new fluid. Raise the driver side, as we all know, and support safely using axle stands at the body lift points (where the factory tire jack goes). And fill slowly until the fluid begins to run out.

You may want to use replacement sealing washers for the drain and fill plugs if the copper washer look rather shabby, are several distorted or indented.

Some M47 transmissions will have at least one, yet maybe both plugs, will have the conical recessed magnet. With one or two magnets, these may be full of bright silver dust and fragments. Don't lose heart that the damage is so severe your M47 has a limited life expectancy. Yet, as with the unknowns as to prior owner abuse and incorrect fluid or low fluid level, and abusive use, keep an ear to the transmission.

The M47 will make noises with new fluid if the prior owner use and abuse as accumulated such that the fifth gear assembly carrier bearings have worn as to create a whine or groan when engaged in that gear. Sort of like a US army Willy's jeep would make even new.

If you hear gear noises at in all gears save for fourth gear, that sends engine power out through the main shaft to the transmission output flange (a 1:1 ratio), you may expect a limited life expectancy.

You apparently can still purchase a new M47 II from Volvo. Alternately, a used Ford T-5, newer and beefier Getrag, inspection and refit, like new front and rear seals, and replacement seals between the flanged compartment sections, may mean you can keep some sort of manual transmission on your 200 or 700 series Volvo. At some price and modification.

You may also luck out and get an junkyard pull M47, that with inspection, may be a ready replacement for your failing M47 transmission. M47 Rebuild prices at repair facilities can run from 600$ to 1400$ Some replacement parts may not be available.

So, please be informed.

Hope that helps.

MacDuff.
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1972 164 with M410 manual transmission is my dream, someday