Trans fluid level check in a '57 ?

[TJ Hopland]

Do you check the fluid in a 57 when its running or not?   I have been working with one that leaks pretty bad, like the puddle creeps out from under the car after a few weeks.  When I was refilling it today I noticed the dipstick doesn't say anything other than transmission, full hot and add. That got me thinking is supposed to be a while not running thing and we have been overfilling it?

[The Tassie Devil(le)]

Every Auto Transmission I have worked with, thy always say that the checking is done with the trans oil up to operating temperature.   And checking with the engine running, except in the case with Ford where the checking is done within a few seconds after shutting the engine down.

Bruce.

[TJ Hopland]

I was assuming its running but it also seems like the majority of the dipsticks said on them engine running level park.  I found a manual but it just says check the Hydra-Matic manual for how to check and add fluid. Guess I should see if I can find one of those online.

[TJ Hopland]

Found a manual and it says running warm.   Its a Pontiac manual but I assume its the same transmission.  Gonna bookmark the page for this manual, looks like a lot of interesting information there about how the thing works as well as the basic info on what the difference is in the 2 D's.

I was kinda hoping maybe we had been overfilling it and that's why it leaked so bad but no such luck.  Something must have got missed or done incorrect with the rebuild a few years back.   

[Lexi]

While a year older, the '56 is supposed to be checked in N or P with the engine running at above idle for 1.5 minutes to ensure fluid coupling is filled. Check level which should be 1/4" below F (full mark on dip stick) or at the full mark if the fluid is hot. Level is checked with engine running. This is from my 1956 Cadillac shop manual. Clay/Lexi

[TJ Hopland]

Ya that sounds like about what the 57 "Strato-Flight" manual I found said.  I may have been reading the full hot mark as the add mark so I may have been slightly overfilling but it indicates that that distance is a pint and this leak seems to be way more than just a pint of overfill getting expelled.

I kinda skimmed other parts of that manual and it said you can push start them but can't tow with the rear wheels on the ground or drive shaft installed.  I would have thought the rear pump would help with the towing at least for lower distances and speeds but apparently not, sounds like it was mostly there for the push starting.   

Other interesting note is it said if you can't get Strato fluid from your dealer you could use 20 weight motor oil but should drain it and replace it with the right stuff as soon as you can.  Have not found as much about the Cadillac version, it doesn't seem like they came up with their own name for it or the fluid?

Was there a separate transmission manual for Cadillac in this era or because it was standard it was just part of the main manual?  Guessing at the time maybe more Pontiacs came with manuals so that is why the auto was a supplement?   Which other GM's used this trans?  Or was it just Cad and Pontiac? 

[Roger Zimmermann]

Oldsmobile used also this transmission. Pontiac had fine detailled specific manuals; for Cadillac, it was into the regular shop manual. I don't remember if Olds had a specific manual for the transmission, but I doubt. I had many manuals from the fifties, but I sold my inventory years ago.

[Lexi]

Roger is correct. Lots on the transmission in the Cadillac Shop Manual for 1956, but as that turned out to be a cursed year for the Caddy transmission, I am not sure what changes should have been made to the Shop Manual to reflect the needed revisions AFTER publication of that manual. Other than the 1956 Cadillac Shop Manual's 1st printing in October 1955, there were no revised editions published. Time to check the old Cadillac Serviceman and Rountable publications for updates as well as various Service Letters and Bulletins (some of which were restricted), and also the Master Parts list for up to date replacement part numbers. The MPL consulted should have revised pages dated up to December 1956 to catch all new part numbers. First publication of the 1956 MPL would be in March of that year, so many of the parts changes are captured. But I suspect not all. In that event, consult the 1957 or perhaps better yet, the 1958 MPL for this information. Most if not all of the parts necessary to keep these Hydra-matics operational were being produced by 1958.

While the General Service Letters and the Bulletins, (some of which were for Service Manager eyes only), are obscure; other 1956 Cadillac transmission publications would include the "1956 Cadillac Hydra-Matic Course", as well as the "Parts Requisition for Cadillac Hydra-Matic transmission" booklet. Title is self explanatory, and these seem to have been more or less routinely published at least in the 1950s. I have a couple of them, one is subtitled "Series 1956 thru 1960". That would be very useful as by 1960 GM had ironed out most of the kinks so this parts list which includes the years 1956/57 is a keeper. The other one I own does not have a subtitle, but looking through the pages it seems to cover the period of 1950 to 1957. There may be other differently titled service-like letter items, but I would have to check.

Lastly, there is spiral bound "book" bound with one of those black plastic combs, titled; "Hydra-Matic Transmission Service Manual", (a Paul Marsh Publication from Detroit). Copyright date for this is 1956, covers Cadillac transmissions up to '56, but sadly it almost certainly will not reflect the changes that Cadillac had to make early in the 1956 model year. Things got so bad that I have a top secret bulletin that basically says if the owner comes in with trany issues, just give him a new transmission. Secret warranty stuff.

1956 was the bastard year for Cadillac, as that year of Caddy is the black sheep of the Cadillac Motor Car Division for the 1950s. Lots of issues when introduced from the new engine and trany to one year only parts. But we "all" love a challenge, right?  Clay/Lexi

[Jim Miller]

While a year older, the '56 is supposed to be checked in N or P with the engine running at above idle for 1.5 minutes to ensure fluid coupling is filled. Check level which should be 1/4" below F (full mark on dip stick) or at the full mark if the fluid is hot. Level is checked with engine running. This is from my 1956 Cadillac shop manual. Clay/Lexi



This is what the 57 service manual says. I've found if I don't follow this I was getting bad readings. So I rev the warm engine for about a minute and a half and then immediately take a reading while in park and ideling.

[The Tassie Devil(le)]

.....I kinda skimmed other parts of that manual and it said you can push start them but can't tow with the rear wheels on the ground or drive shaft installed.  I would have thought the rear pump would help with the towing at least for lower distances and speeds but apparently not, sounds like it was mostly there for the push starting.   

There is a reason why they do not recommend tow-starting these cars is because when the towed car starts, there is the possibility that the towed car could leap forward, into the back of the towing vehicle.

I started my own 1955 Chevrolet by towing it when it had a flat battery, and as I was the driver of the towed car, I was well aware of the chances of running into the back of the car in front.   (it was a case of never using a short tow rope)

Bruce.

[Big Fins]

There is a reason for checking transmission fluid when it's hot. Due to the chemical make up and the friction modifiers in it, the fluid will expand about 1 pint when hot, over room temperature. It must also be checked with the engine running to get the correct level, to be sure the torus/torque converter is full.

Failing to have the correct level will cause either foaming in an overfilled situation, or air being sucked up into the pick up on turns, stops and starts in a low level condition. Fill it to about 1 pint low, drive it a good 10-20 miles to heat up the fluid to operating temperature, then top up accordingly.

[TJ Hopland]

When did they start printing more info on the sticks?  That's what got me thinking was while I was standing there pouring in a couple quarts I was admiring that the writing on the stick was nice clear raised letters like it was a casting and it even said transmission on it but didn't say anything about running or not.  I remember a friend had a 50 Nash with a HydraMatic and on that there was a hatch in the hump/tunnel you opened up and I remember that being like a pipe elbow sort of like a manual you just filled it up to the threads.  Don't recall if that was the unusual part or if that was where maybe I got the idea there were some you checked not running. 

The fact that it said transmission now makes be wonder if there were issues with people mixing up the sticks?  Trying to remember what the engine oil looks like, were some of those larger so you could switch the sticks?   I'm just thinking of the 70's where the engine oil was a tiny tube.  Or was the issue that people would just grab the first stick they saw and assume that was the engine oil since they may have been used to manuals where there was no second dipstick?  If they were checking their 'engine oil' with the engine off I would assume it was always looking overfilled so were people running their engines out of oil?

Did every car brand do their own tweaks on the HydraMatics?  Like could you swap a Pontiac with a Cad?  Or like Nash or was it Rolls?   Did all their service manuals have a little different setup and adjustments to make it 'their own'?   Like I would assume Pontiac would be going for a little more performance where Cad and Rolls were going for comfort.  Pontiac says the right D mode is for performance.  Did Cad describe it the same way or did they have a different 'tune' so right D was normal vs Pontiac said left D was the normal one?

[Jeff Rosansky CLC #28373]

Don't feel too bad. Mine leaks like it was stabbed with a butcher knife.
But, she shifts fine so will let her leak until she needs to come out.

[Roger Zimmermann]

Recently, I overhauled a '56 Cadillac transmission for a man who has 4 or 5 such cars. He installed the transmission into the car and could hardly drive. He called me, explained what was happening. Before he would remove the transmission from the car, I suggested that he should remove the oil pan to have a quick check if metal shaving was in. He called me later saying that just two or three liter oil came out (should be at least 8 or 9).
After some ideas exchange, I suggested that he sould compare the oil tube and the stick with another '56 car. He called me later again, saying that he has the wrong stick in his Seville, much longer than the correct one.
After the right quantity of oil went into the transmission, all was OK!
So, with an unknown car, it hard to tell if all accessories are correct. In "my" case, the stick for 1956 is also good for 1957 and 1958 on Cadillac cars. So, there is plenty possibilities to have something wrong.

[Lexi]

Very good point Roger. Ran into that once myself. Clay/Lexi

[TJ Hopland]

I did hear the previous owner really liked 57's and had many at times and over the years.   I would assume that also means lots of parts and parts cars too.   Hopefully he also knew what the proper stick was but I guess that is a possibility.   Pretty sure when its showing low its low because even tho it still works its noisy.  There is a point when filling that it starts to burb out the tube.  I suppose that could be some sort of sign?  I'm not talking about burping fluid, just a burp in the funnel that fits fairly snugly in the tube.