Fluid Drive M6 Trans or 3 Spd Standard

Hi All, its been a while since I have posted on this site, here is my question. I have a 1948 Chrysler Coupe, the engine and trans are a big block Canadian 218 and a 3 spd trans and regular clutch, from a 1951 Dodge or Plymouth. I was pondering switching this vehicle back to the fluid drive and M5 trans, I have a parts car with these items. Or would just adding the fluid drive and a 3 spd trans workout. My 3 spd trans could be used I would think as long as I changed the input shaft to work with the fluid drive. I personally like the regular clutch and 3 spd trans that I have now, my diff is a 3:54. I find this setup has a lot of get up and go, and is much simpler than the M5 set-up and I don't mind shifting. The car can take off from a dead stop in 2nd gear no problem, these Flathead 6s seem to have a lot of bottom end torque.What might the pros and cons be in this swtiching around. I did post this question on P15 D24 and got a lot of good feedback,I was just wondering what guys on this site might think, especially Jon Robinson..........Thanx Fred

Fred:

The first thing to do is confirm what you actually have in that car. The Plymouth 218 was the SMALL-block six. Measure the length of the cylinder head. If it's about 23 inches long, it's the small-block six from a Dodge or Plymouth, but if it's about 25 inches long, that's the big block engine from a Chrysler or DeSoto.

Are you saying this car once had the M-5 and now has a three-speed manual transmission with a dry clutch? This is odd because, on a Fluid Drive car, the cross-member the bell housing sits on is about seven inches further back on the frame than cross-memnber for the dry clutch. It's no easy matter to switch back and forth.

The M-6 is a much simpler transmission in terms of wiring than the M-5.

I would be careful about changing something that works. If they moved a cross-member, you'd have to go to a lot of work to move it back. This job could escalate on you.

JON

Jon, In Canada, the 218, 230, 251, and 265 were all 25 inch blocks, all the same block cast and built at the Windsor Ontario plant. The cross member was moved but not 7 inches, the original holes are still there so it might be a matter of moving it back. I also have a 1947 Chrysler coupe parts car, it has the M5 and Fluid Drive and all the hardware, I could possibly transplant these parts to my car.

Basically, I am at the pondering stage, the standard 3 spd and dry clutch are very simple, the car can take off from a dead stop much quicker also. My project will not be totally original, but I hope to be close, she will also be a driver and not a showgirl............Thanx Fred

What I was picture was the cross-member welded to the frame as they were 1949 and later. I've worked on a lot of 1946-'48 Chryslers and DeSotos, and I just wasn't picturing the cross-member being moved without cutting and welding.

Sounds like it might not be that big a job after all. I like originality, and I think it would be really cool for you to have a semi-automatic back in there, even if it's an M-6.

JON

Thanx Jon, now what may the likelyhood of me using this trans and fluid drive from my 1947 Chrysler parts car, without rebuilding them. Were these fluid drives known to last along time without major problems. The other thing is the crank on my current engine, I wonder if it will bolt up to the fluidirve flywheel set-up. Time will tell. At the moment I am reparing rusty floor and rocker patches, sure would have liked to find a car without the rusty floors, not likely in my parts, (Central Canada)...........thanx for your help Fred