48oldsguy

Hydramatic Transmission oil level check

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Does anyone have a good way to check the oil level on a 1940's Oldsmobile hydramatic transmission.  The manual says to take the check with the dipstick when the car running in the drive position. With my foot on the brake to keep from moving forward in the Drive position, I REMOVED THE TRANSMISSION DIPSTICK TO READ THE OIL . The dipstick reeding is not very practical in this situation because the hot sloshing oil is all over the place and trying to get an accurate oil level check from the dipstick is not very practical.  I certainly do not want to overfill the transmission nor allow the oil to go below. the manufacturers recommendations.   In particular I am referring to my 1948 model 66 Oldsmobile Station wagon {woodie)

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Are you sure the transmission is supposed to be in the Drive position and not in Neutral? I have included a section of the GM Hydra-matic Transmission Service Manual from 1946-1955 that explains the proper procedure for checking the fluid level. See step 2.

IMG_0259.JPG

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This is part of the confusion, others have brought up the matter of GM bulletin that later specifies that the car needs to be in the drive selection mode.  In either case trying to get an accurate oil level check by reading the fluid level on the dipstick with engine running has not been very reassuring for me.  I understand why that by design that GM engineering  determined that the only way you can get an accurate oil level check is to warm the oil fluid under pressure from the torque convertor pump.  However, the agitation of the oil ends up splattering against the dip stick making it difficult to determine a precise oil level on the dipstick.  Thanks for your response you may be correct, at this point Im just not sure which is the correct transmission setting, drive or neutral.  Again, in either case the dip stick oil level indication has frustrated me many times and I think I may have overcompensated my transmission oil servicing on some occasions.

 

 

 

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Personally, I have owned 4 older floor-fill Hydramatic cars and serviced another one for a friend. I check the fluid after driving a reasonable distance on a flat surface with everything at operating temperature and the transmission in neutral. I keep it at the full level on the dipstick and that's about all you can do. I don't remember any splattering and never had a problem with any of those 5 Hydramatics. 

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I just tried to check my transmission oil level again today.  With the car in neutral, warmed up, I removed the dipstick, to wipe it clean and stuck it back  in all the way and quickly removed it.  The oil level was almost to the top of the stick.  I tried again several times and got various high and low oil level readings, none of which where very definitive.  Question:  If the oil level is low how would know how much to put back in?

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That would be easy if you  could tell what the oil level was each time.  In my case as stated before, I have  not been unable to get a definitive oil level indication.  

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Is it possible that you are having trouble reading the oil level because it is already over-full? I think I'd drain it, fill with the capacity called for, and then check and see what you get.

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I get no indications of foaming (overfill) and some of my dipstick readings appear to be low.  The transmission also leaks quit a bit. I understand that the transmission holds 11 quarts oil. If I remove the transmission pan drain plug will I still have residual oil left in the  torque converter.  If so how much, and how do I drain that oil to insure the transmission is totally empty.

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I believe the fluid coupling can be drained - otherwise you'd have a heck of mess when unbolting the torus cover from the flywheel (for transmission removal). I could be wrong on that. My experience with that Hydra-Matic was at least 25 years ago.

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46 minutes ago, Oldsfan said:

I believe the fluid coupling can be drained - otherwise you'd have a heck of mess when unbolting the torus cover from the flywheel (for transmission removal). I could be wrong on that. My experience with that Hydra-Matic was at least 25 years ago.

 

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I wish there was someway you could get good fluid level indiction without having to run the engine.  Thanks for your comments.

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Just a thought, Try the old fashion way. make sure it is warmed up and put it in park and check it.

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There is no "Park" on these old hydramatics. Reverse is park when the engine is off.   -   Carl 

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Also, I assume you are really having a problem. You HAVE jabbed that clean and dry dipstick down and back just as close to the speed of light as you possibly can  ?    -   Carl 

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I have driven the car to warm up the oil, parked on a level surface, and pulled the dipstick out, wiped it clean and forcefully reinserted it all the down as far as it will physically go many times and have never gotten a clear indication on the dipstick of the actual oil level. The oil is always smeard over the dipstick from top to bottom with splotchy less oily areas areas in between..    

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I wonder if the tube is gummed up, allowing oil to show on the stick where it shouldn't. Maybe the tube needs to be removed and cleaned out?

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On 1/15/2019 at 6:02 PM, 48oldsguy said:

Does anyone have a good way to check the oil level on a 1940's Oldsmobile hydramatic transmission.  The manual says to take the check with the dipstick when the car running in the drive position. With my foot on the brake to keep from moving forward in the Drive position, I REMOVED THE TRANSMISSION DIPSTICK TO READ THE OIL . The dipstick reeding is not very practical in this situation because the hot sloshing oil is all over the place and trying to get an accurate oil level check from the dipstick is not very practical.  I certainly do not want to overfill the transmission nor allow the oil to go below. the manufacturers recommendations.   In particular I am referring to my 1948 model 66 Oldsmobile Station wagon {woodie)

sloshing oil almost suggest to me that there's already too much atf in the trans, i would advise to completely drain the pan and the coupling, refill with 8 quarts, start engine, leave it in neutral, slowly add 1 quart until you have a total of 10 quarts in the trans, if the stick still shows below full, divide the 11th quart (if needed) into 4 parts, add 1 check stick, again until you're sure it reads full and is not sloshing, now if you want to check while in drive gear, pull hand brake and block wheels, let me know what you learn.

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