Tony Concepcion Posted November 17, 2022 Share Posted November 17, 2022 Hello all and thanks in advance for any assistance. I am trying to help a friend who owns a 1948 Chrysler New Yorker that is currently in my possession in Carlisle, PA. The transmission would not go into reverse a couple of years ago and it was taken to a transmission shop that supposedly had an "old timer" who was familiar with it. After taking it out and "rebuilding it several times, they gave up. It DOES currently go into reverse, and has low and second gears. It will NOT shift into final drive at all. I'm familiar with how to drive one, so please lets avoid that topic. I had it brought here because we had a shop locally that had worked on one for me before, but the gentleman is older now and does not want to pull this transmission out of the car. The solenoids have supposedly been checked and are supposedly working. Short of pulling the transmission (which I do not have the ability to do) is there anything else I can look for or confirm? Beyond that, does anyone know a place or person that would be willing to look at it who is knowledgeable about this transmission?? Thanks again, Tony Link to comment Share on other sites More sharing options...
Rusty_OToole Posted November 17, 2022 Share Posted November 17, 2022 Do you have a repair manual and wiring diagram? The symptom you describe could be due to low oil or wrong oil, unlike most transmissions it uses very light oil, 10W motor oil or tractor fluid, TDH type, ISO 22 or ISO 32 grade. Another thing that sometimes causes problems is the idle speed. It needs to be 400RPM when the engine is warm, about half the speed of a modern engine. If the engine idles too fast it won't shift. If the oil level is correct, and the correct thin oil used, next thing is to check the wiring. I won't go into the gory details, although I could if you don't have a manual with wiring diagram. Last would be to go over the various switches and solenoids and see they are functioning. This can be done without taking out the transmission. There are Chrysler bulletins on troubleshooting and servicing these transmissions available on the net. One source is a Chrysler Imperial web site. 1 Link to comment Share on other sites More sharing options...
Rusty_OToole Posted November 17, 2022 Share Posted November 17, 2022 More on the subject=== https://www.web.imperialclub.info/Repair/Lit/Master/012A/cover.htm Link to comment Share on other sites More sharing options...
Rusty_OToole Posted November 17, 2022 Share Posted November 17, 2022 A Chrysler factory film on the transmission Link to comment Share on other sites More sharing options...
Joe Cocuzza Posted November 17, 2022 Share Posted November 17, 2022 Give Dave Brady a call. He is in Emmaus, Pa and he does great work (610) 965-2172 1 Link to comment Share on other sites More sharing options...
c49er Posted November 19, 2022 Share Posted November 19, 2022 (edited) The "Hydraulically Operated" M-5 Chrysler transmission if in good operating condition can be checked to see if it will auto upshift.... By just removing the 30 amp trans relay fuse...just drive off and imediately let off the gas...should instantly upshift. It will not downshift at any time with the fuse removed untill at a complete stop with the clutch in. Do not back up during this test with the fuse removed. This is only to test the hydraulic upshifting of the M-5 transmission. As mentioned idle speed and oil level needs to be proper. Edited November 21, 2022 by c49er Spell check (see edit history) 1 Link to comment Share on other sites More sharing options...
Tony Concepcion Posted December 2, 2022 Author Share Posted December 2, 2022 Thanks for all the advice. I pulled the fuse, still no shift. I didnt have access to a lift until today to check the fluid.....well guess what? They used normal automatic transmission fluid!!!! I knew about the 10w all along, but I didnt suspect they would have not known that! Anyway I drained the fluid but only got about 2 quarts out, so I think I'm missing something? I have a one gallon can of the correct fluid (old stock) had on a shelf) but I can't find the capacity in the Motor's manual I have. I don't have the factory service book. If no one knows off the top of their head, I'll be researching more tomorrow to learn about proper fill and capacity. Thanks again! Link to comment Share on other sites More sharing options...
Rusty_OToole Posted December 3, 2022 Share Posted December 3, 2022 Drained the fluid from what? Transmission holds about 2 3/4 pints (this from memory) Fluid coupling somewhat more. When you fill the fluid coupling thru the hole in the floor boards the hole is located in such a way, that if you fill it up as far as possible it leaves the correct amount of air space. There must be some air in the sealed unit to absorb pressure when it gets hot. The unit will continue to function when low on oil. In fact an old hot rod trick is to drain off some of the oil, this gives the same effect as a high stall speed torque converter. 1 Link to comment Share on other sites More sharing options...
Rusty_OToole Posted December 3, 2022 Share Posted December 3, 2022 On re reading your original post I wonder what the problem was? Will the trans not shift into high range manually? Or does it go into high range, start off in 3d then refuse to shift up ? If it is the former, most likely the linkage is out of adjustment. Unless the "genius" who rebuilt the trans messed up something inside. Link to comment Share on other sites More sharing options...
Tony Concepcion Posted December 3, 2022 Author Share Posted December 3, 2022 Rusty, the original problem was it will not shift into the last gear in high range, so as you said, you can start off in 3rd but it refuses to shift up. I will be replacing the fluid tomorrow (i only have use of the lift on the weekend) and if the transmission only holds about what you say, i have enough of the correct fluid to re-fill. I will still need to investigate the fluid coupling to see what they put in there. Thanks! Link to comment Share on other sites More sharing options...
Tewwillis Posted December 3, 2022 Share Posted December 3, 2022 Hi Everyone, I want to thank you all. I have a 49 Chrysler Windsor, which I emailed on info about the fluid drive transmissions and Rusty replied. I lost the web site Rusty gave me and found it in the above emails. My transmission has trouble shifting in low gear (but the idle is all messed up and idles high. The seller had the 6 volt battery connected backward & turned it up, or tried), but it seems to shift ok in high gear. My question: if the transmission is full of fluid and shifts ok in high gear will it hurt to drive it, only short distances of 3 or 4 miles? I'm trying to find a mechanic who knows & has worked on fluid drive transmissions, checking out the electrical part and adjusting the transmission but it's hard to find one. Many Thanks Tom Link to comment Share on other sites More sharing options...
Rusty_OToole Posted December 3, 2022 Share Posted December 3, 2022 You won't hurt anything by driving in High range. All normal driving is done in High range, that is, with the lever in High and it starts off in 3d and shifts to 4th when you lift your foot off the gas pedal. Low range is for starting on a steep hill, driving thru snow, sand or mud, or starting off with a heavy load or towing a trailer. Or when extra acceleration is wanted. You don't need Low range most of the time. If you have a manual and understand how the system works it is quite simple. It is easier if you break it down into separate systems, fluid coupling - transmission - electric control system. The fluid coupling only has 2 moving parts. The transmission is like a typical manual trans with the addition of a hydraulic pump and shifter. It only has 2 positions. The electric system has basically 2 positions, one switch for when the throttle is closed to allow shifting, the other when the throttle is wide open for kick down. Then there is a governor and 2 switches on the transmission. It is a simple job to adjust the idle speed. Once the motor is warmed up and the choke off, adjust it to 400 RPM. This is very slow, about half the speed of a modern motor. The engine should just tick over smoothly without a tremor. 1 Link to comment Share on other sites More sharing options...
countrytravler Posted December 3, 2022 Share Posted December 3, 2022 Try talking to this guy. Link to comment Share on other sites More sharing options...
c49er Posted December 4, 2022 Share Posted December 4, 2022 (edited) Two things as mentioned above are most important for these "Hydraulically Operated" M-5 transmissions to auto up shift... 1st....idle speed must be close to 450 rpm.. 2nd...transmission 10W oil full to the bottom threads of the filler plug hole on the passenger side of the case. With these two items assured of.... With the relay fuse out and a quick road test starting out in high range... Accelerate up to 20mph and let off the gas for say 2 seconds. The M-5 transmission should instantly click/clunk into 4th gear...that's it. If it doesn't auto upshift there is an internal transmission hydraulic oil pressure issue or a internal mechanical problem... Edited December 5, 2022 by c49er (see edit history) 2 Link to comment Share on other sites More sharing options...
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