Trans swap for synchros

[Mertz]

I’m just getting ready to pull the trans out of my 1940 Plymouth. I have the top off and the gears look fine. The bottom set seem to rock a bit. There are no synchros and wondered if there is a direct swap for my 3 speed that has synchros. I’m trying to keep this as original as possible but would like a better shift experience. 

[Jerry Roberts]

The 1941 Plymouth truck three speed had synchros in second and third gear , It is a direct swap in . I didn't know that the 1940 didn't have synchros too . The later 3 speeds up through 1947 have synchros but I can't remember which years exactly . 

[Mertz]

I’m looking at the manual and it does show a clutch gear. Is that the same as a synchro?  I know Cadillac had them since 1928. It would be great if I had second and third synchros. 

[Frank Elder]

You never did answer my question @Mertz........

[Mertz]

I’m sorry but what question did I not answer?  I would happy to give you any information I have. 

[Frank Elder]

It was in another post....tongue in cheek I asked if you were related to Fred and Ethel, It was meant to be humor...lol.

[DJ194950]

He might be a few years to young to even know what you are asking, heck it is Almost before my time and I am 70 YO! ?

 

DJ

[Mertz]

Oh I know Fred and Ethel. When I tell people my name is Mertz I tell them about Fred and Ethel. My name is actually Marcel Wuts and my best friend from high school when we got to college, after a number of beers, reduced it to Mertz from Mar and ts. I designed a memorial for the fallen police officers in Washington and the plaque reads designed by M Mertz Wuts. 

[Frank Elder]

Wonderful story thank you and thanks for helping to honor the fallen policemen. So Wuts up?...lol.

[keithb7]

In my 1938 3 speed  equipped Plymouth car, I have a "clutch gear". A double ended synchromesh that works speed to match adjoining gears. If you are interested in learning more see here:

 

 

Edited December 4, 2020 by keithb7

[Mertz]

Wow that was a great video!  I learned a lot. On my trans I have straight cut gears. I will see if I can get a better picture and send it. I’m planning on having a local shop go through it. It does appear to have the clutch gear. 

[Mertz]

Wow that was a great video!  I learned a lot. One my trans I have a straight cut gear at the very front of the top cluster. It has stepped teeth. I thought they were worn but that’s the way they are cut. It looks the the first reverse gear maybe covering it. I will see if I can get good picture and send. I’m planning on having a local shop go through it. 

 

I just went went out and took some more pictures and looked at my manual and it appears I am blessed with a 4 speed but I don’t see a clutch gear. Is this trans synchronized?

[Mertz]

I cleaned off about a 1/2” of dirt off the top cover and found a code.

[1949 Wraith]

No synchro in that tranny. You will have to look for a later model truck 3 speed with synchro. I have a 3 speed from a '51 truck that I am thinking of converting for my '42 Fargo if the 2nd gear synchro in it gets much worse.

[keithb7]

Straight cut, non-synchronized spur gears in that tranny. From what we can see, the gears actually look be in real good condition too. Someone has been tender and kind to that tranny for decades. I like how they shaped the leading contact edge of the sliding gears. Not a straight edge to be seen where it makes contact. Nice work by the gear maker!

 

Glad you liked my video. Those comments make it all worth while. Helping others is my goal.

Edited December 5, 2020 by keithb7

[Mertz]

The gears look to be in very good condition. I don’t see a lot of wear. The odometer on the truck shows under 30000 miles. It was a Montana farm truck. Looking at its overall mechanical condition I believe this might be correct. I will keep the original transmission to keep it original and have read shifting a 4 speed without synchros is not has hard as a 3 speed. The gears show not a lot of crashing. I plan to keep the 4 speed and have the bearings and seals looked and replaced as required. BTW there are no signs of fluid leaks from the trans. I will know more when I pull the transmission. I can double clutch if I have to but it will probably be only on the downshift. 

 

Im really excited about doing this truck and it’s overall condition. Even the rubber boots on the driveline are in very good condition with even the clamps only slightly weathered. I’m documenting everything with photos. 

[Jim G]

10 hours ago, Mertz said:

The gears look to be in very good condition. I don’t see a lot of wear. The odometer on the truck shows under 30000 miles. It was a Montana farm truck. Looking at its overall mechanical condition I believe this might be correct. I will keep the original transmission to keep it original and have read shifting a 4 speed without synchros is not has hard as a 3 speed. The gears show not a lot of crashing. I plan to keep the 4 speed and have the bearings and seals looked and replaced as required. BTW there are no signs of fluid leaks from the trans. I will know more when I pull the transmission. I can double clutch if I have to but it will probably be only on the downshift. 

 

Im really excited about doing this truck and it’s overall condition. Even the rubber boots on the driveline are in very good condition with even the clamps only slightly weathered. I’m documenting everything with photos. 

Good on you for keeping it as original as you can and learning to drive straight gears. It's not that hard, and is a nice skill to have when driving one of these old beasts. Personally I love the sound of those old gear boxes. I've had the best results driving without synchros is to relax, take my time, and be gentle and it just sort of falls into gear. 

[Mertz]

I’m a firm believer in originality. I have restored a house which was a long term project but it remains very close to how it was built in 1906 including some items such as the staircase that came out of the Sears catalog. 

 

Once I got into this truck I noticed how very original it is. The wiring harness is near perfect. The front brake pad are good but will be replaced. There is a lot on the truck that just needs minor restoration. That will keep my costs down. It is only original once. My biggest challenge will be the body work. Some replacement front fenders would help a lot.