Jump to content

Transmission Identification help

Go to solution Solved by Merle Coggins,

Recommended Posts

Hey fellas, need help Identifying a couple of transmissions dad and I own. Got them from an old farmer with a couple of 250's a number of years ago. I used the one pictured with a 218 to drive a frame around and I'd like some info. I'm not sure if the thing come down and off to the side is for 4wd or a PTO maybe?




Link to comment
Share on other sites

Easy way to tell a synchronized from a non-synchronized PH 4 speed is to look at the drain plug. A synchronized unit has the drain plug running horizontal at the bottom rear of the case while a non-synchronized unit has the drain plug running at an angle in the same general area. At least that is what the parts book shows talks about.

Link to comment
Share on other sites

I'll check on the drain plug tomorrow. I'll dig up the other one and see if its the same exact as it might not be. Need to research the difference between synchro and non sychro as I have no idea what that means. Is the 3-24-49 the date of manufacture? and is there a way to tell what a transmission is just by the cast number? I've had a nightmare of a time trying to ID a 3 speed from a coronet with just google


Link to comment
Share on other sites

  • Solution

Yes, that's likely the casting date of the case. I've never seen a model ID listed for these transmissions. They're just New Process 4 speeds. I believe the later version is refered to as the NP420. Non-synchro vs. synchronized transmissions refers to how the sliding gears function. In the early spur gear, non-synchronized transmissions the gears have straight cut teeth and there are no synchronizers to aid in shifting. With these transmissions you need to learn the art of double clutching your shifts. The later, synchronized, version was introduced into the Dodge trucks in '51. This transmission has helical cut gear teeth for quieter operation and syncronizers on 3rd and 4th gears for easier shifting. Pretty much all modern transmissions are of this synchronized type now. 


Another way to know the difference, and how I identified this one, is that on the earlier spur gear units the PTO drive was ahead of the fill/level plug whereas the later, synchronized, units have the PTO moved rearward with the fill/level plug towards the front. 

Edited by Merle Coggins
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Terms of Use