hy-drive transmissions

[p24-1953]

i have a 1953 plymouth and have not found a lot of information on the hy-drive transmissions. Are these transmissions dependable? are the sutiable for todays highway speeds? can you install a overdrive on them? are they worth keeping or should i switch it out?

[greg g]

The hydrive is basically a dependable unit. It does however run on oil shared with the engine. An oil change on a hydrive car is in the neighborhood of 11 quarts. Check the transmission section of the ALLPAR site. some good info there. the HYdrive was basically a hydraulically shifted standard trans.

http://www.allpar.com/mopar/hydrive.html

[Rodger S-11]

1953 Plymouth Person

By now you know the transmission assembly that you have is OK. Did you learn the transmission shafts and clutch size were beefed up over the non Hy-Drive unit due to the added torque from the fluid coupler ???

The any brand multi grade 30w oil ( the heavier blend 20-30w is better ) that goes into the engine is for the engine and coupler. The transmission still needs its standard transmission oil just as any other three speed manual.

If you happen to find an era over-drive, it can be bolted to the end of the three speed transmission. But why ???

How does your 1953 Plymouth drive train compare to an 1953 Ford 6 cylinder or Chevy ???

Do you have the "Bridge" or the "Brook" ???

Rodger & Gabby

1947 S-11

[p24-1953]

1953 Plymouth Person

By now you know the transmission assembly that you have is OK. Did you learn the transmission shafts and clutch size were beefed up over the non Hy-Drive unit due to the added torque from the fluid coupler ???

The any brand multi grade 30w oil ( the heavier blend 20-30w is better ) that goes into the engine is for the engine and coupler. The transmission still needs its standard transmission oil just as any other three speed manual.

If you happen to find an era over-drive, it can be bolted to the end of the three speed transmission. But why ???

How does your 1953 Plymouth drive train compare to an 1953 Ford 6 cylinder or Chevy ???

Do you have the "Bridge" or the "Brook" ???

Rodger & Gabby

1947 S-11

i did not know that the transmisson required transmission oil. I was under the impression that it was all motor oil. where do i change it? and how often should i change it? by the way i have a cranbrook. a overdrive would be nice so that highway speeds would not be so rough on the engine

[Rodger S-11]

1953 Plymouth Person

I'll start with the clutch. Due to the added torque you may have 12 blk spgs w/230 lps each. The typical regular three spd has 9 lt blue that have only 157 lps each.

In 1953 MoPar had one version Torque Drive as yours that used oil from the engine and one version Torque Drive that had an internal pump. The bell housing for your version had an bolted seam around it at the bend of the bell.

If you have completly drained the engine oil, you know that you did the oil pan plug, the engine filter ( not on Ford or chevy's ) and then the Torque Convertor. ( for those of you that have no clue, ... he opened the passenger front door, pulled back the carpet/mat from the passenger side transmission hump, opened the access plate on the transmission hump, and then "bumped" the starter w/o the coil connected until the torque convertor unit's plug was visiable so he could remove it. Went under the car in all safe manner ways to remove the cover on the front of the bell housing. And then "bumped" the starter again until the plug hole was at the bottom with oil coming out into an catch pan. After his break and there was no more oil dripping, he cleaned the mess and returned all. )

Since the best oil of 1953 is not up to the grade with the cheapest oils of today, the house brand engine oil from WalMart or where ever is OK.

Now to the latest question from you. All Manual shift transmissions, even from today's newest vehicle, drains and etc mostly from the passenger side. From under the passenger side look at the side of the transmission. You should see two bolts with an square head. The lowest to the ground is the drain. When the dripping stops at about 2 3/4 pints later, replace this plug.

Just above the drain plug is another plug made the same way. Remove this add/fill plug and slowly add about 2 3/4 pints of 20w engine oil. When it starts pouring back out the add hole, stop since it is now full. Replace and tighten the plug.

The Oil Bath Air Cleaner will use an 20-50w multi-grade engine oil to the fill to here line.

Your car was designed for an honest 60 MPH. Sure it can go much faster, just do not inform your insurance company. ( ...Sumthin about an high center of gravity, yester-years suspenstion design and etc. ) Others with an viewing of the car will understand the steady 60 MPH vs the 83 MPH.

You may find out the 205 x 75 x 15 tire of today will fit the rims and the spare tire holding space. Do not let your helping neighbor twist the wheel studs on the left side off since they are left hand threads and he may not know this.

Rodger & Gabby

COS

[Plymouthy Adams]

of the comment above I draw exception to a couple areas..first if the critical transmission oil..as it is separate of the engine and torque converter...the suggested oil of 20 wieght is not the recommended oil per the book..it is 80W and the need for this oil compared to the 20W is for the protection of the gear teeth when meshing..this is the "shear" factor built into the oil..it is designed not to displace when under extreme stress..in case this is a typo error..just want to let the book recommended be know..

Second and minor is that the Hy-Drive has a inspection/drain access cover on the very bottom of the transmission unlike the older Fluid-drive that did indeed have the access cover under the carpet pad..so there should be no need to disturb your floor covering looking for this access plate. Remove cover, rotate till drain plug is in place plug..remove drain and replace...the engine will by way of its oil pump fill the torque covertor to full...and maintain that level..

[p24-1953]

i knew about drain the convertor and i knew the oil bath but did not know about the to drain hole on the transmission, so use 80 weight? thanks for the heads up

[Plymouthy Adams]

per my Plymouth Service Manual that is the requirement...Lubrication and Maintenance Section:

Air Clearner...above freezing temp.....SAE 50

below freezing temp.....SAE 20

Water Pump..............water pump grease only

Rear Axle..................temps above 10 degree...SAE 90

below 10 degree...SAE 80

Tranny and OD......... SAE 80 ( fill to level of filler hole)

It is recommended by the factory for those cars Hy-Drive equipt..oil change twice a year with spring and fall the suggested time frame..

[Normspeed]

p24, if you're in the southern California area you might check the thread about the motor and HyDrive for sale. You could have a nice parts transmission or one to rebuild in your spare time, almost free. With a motor attached:D

[Rodger S-11]

Hola Class

I have an 582 page De Soto Factory Service Manual that says S-16, S-17 & S-18. That is were I got the information from.

I will go back and scan the pages of the FSM if any would like.

Rodger & Gabby

COS

[Plymouthy Adams]

Roger..think that is the answer..the DeSoto did not get the Hy-drive tranny...it used the flluid drive set up shared with Chrysler (M6) and in 54-55 (high as my DeSoto reference goes) they got the Powerflite...think the Plymouth was the only model with Hy-Drive but they all shared the first Powerflite...service to the fluid drives is through the upper access panel on the passenger side of the floor hump...

[Rodger S-11]

Tim

Me always thinks the Plymouth version was the engine fed oil torque drive with an clutch only using an three speed manual transmission.

The upper divisions show an engine fed torque drive and the pump fed unit ( see pages 95 and 115 of the S-16, S-17 and S-18 FSM ). This same information is also with the Chrysler and the Imperial's when it was used. The quick spotter's guide to an engine fed Hy-Drive or Fluid Torque Drive unit when looking at it is the two piece bell housing made from an mag type material.

I had an Plymouth version once that I wanted because I ( duh ) some-how felt this could work on my 1953 De soto. This De Soto V8 unit was only with the std fluid coupling and M-6. I ended up giving all the Plymouth std transmission parts to an friend of mine for his Christmas Gift that year ( 2005 ) ( ... his Dodge used the same three spd transmission ).

I am still looking for an pump fed Fluid Torque Drive Unit to bolt to the same De Soto V8 and M-6 Transmission. Until then, I'll use the slower to take off Fluid drive and M-6 ( aka Tip-Toe ).

Rodger & Gabby

COS