Understanding the Dynaflow

[Paul Falabella]

First time Dynaflower. Just read a couple of threads on the regular and irregular functions of a Dynaflow. I am guessing different years have different characteristics. With my 55, there is no perceptible upshift on a normal takeoff. If I press down on the accelerator I can feel a noticeable kick down in the tranny and the sound of the secondaries. While not JATO, the acceleration ain't bad for a 60 year old sled.

Sound normal?

[supersix]

You are correct. This sounds normal. There is no noticeable shift when starting in "Drive". There will be a shift if starting in "Low" and manually shifting to "Drive".

[Bhigdog]

There is no up/down shift in a 55 Dynaflow. There is a variable pitch stator in the torque converter that can act (sort of) as a passing gear. If you have a shop manual there is a very good explanation of it's operation complete with colored diagrams explaining motive flow in various configerations...............Bob

[Guest kaycee]

As Bob said, there is no gear change in the '55 Dynaflow although it feels like it when "kicking the gas pedal down". 1955 was the first Dynaflow with the variable pitch, and was done with a stator change in the converter. I rebuilt my first one in my first Buick V8, a '55 Century when the car was only four years old, and it was a fast car in its day. 'Wish I still had that car, my first "hot rod". Now all my cars are older and slower like their owner!

kaycee

[trimacar]

I may have told this story before, but just can't pass up the chance to do so again.

In the late 1970's, I was living in Marty's town (Metairie, La.) on the outskirts of New Orleans. One day I changed oil in an early Mustang convertible, and took it for a drive. Sitting on a Ford dealer's lot I spotted a beautiful 1957 Buick, two tone, white and that burnt copper color. Stopping to look at car, I was amazed...it was in near perfect condition with about 15,000 miles on it. Ran so quietly you could barely hear it, and when I picked up a floor mat, on the opposite side was "Buick" in script, the original mats.

They had just taken the car in on trade for a new car, and had to go ask the manager for a price. $1500. I talked to the manager, said look, you're not here to sell old cars, you just got this one, let's turn this one around quickly for you at $1000...and he took it!

Fast forward to a year or more later, I'd taken the car on a club tour, and one of the guys on the tour fell in love with the car. The following week, he came over to test drive, as I told him the car would be available. He took off, and about 5 minutes later came back, and he was agitated. "You didn't tell me the car had a bad transmission..." What, I asked, it drives perfectly... "Yeah, it drives nice, but it never shifts.." Uhh, that's how it's supposed to work, it has variable pitch vanes that....."Nope, you can't fool me, I'm not interested..." and left.

Worked out well, though, I ended up trading it for a 1966 Thunderbird convertible in like condition....

[Pete O]

Yup, it always irks me when the so-called experts in the collector car buff magazines refer to a "smooth shifting" Dynaflow in their road test reviews.

[Paul Falabella]

Good news,it's working OK, just need to fix the leak then.

[buick man]

As Bob said, there is no gear change in the '55 Dynaflow although it feels like it when "kicking the gas pedal down". 1955 was the first Dynaflow with the variable pitch, and was done with a stator change in the converter. I rebuilt my first one in my first Buick V8, a '55 Century when the car was only four years old, and it was a fast car in its day. 'Wish I still had that car, my first "hot rod". Now all my cars are older and slower like their owner!

kaycee

..... Gee you did that rebuild when you were only 4 years old? I did'nt do my first overhaul until the age of 10. You are the man! :cool: Or should I say buick boy.

Paul like everyone is saying, think of the Dynaflow as a fluid coupling. Sorta like , you are going down the road due to fluid pressure hitting a fan and the fan flings it and turns it. Come to think of it, like a old water wheel on a river boat.

[Bhigdog]

Good news,it's working OK, just need to fix the leak then.

A Dynaflow leaking to some extent is just the nature of the beast. The easiest fix is to just put a big piece of cardboard under the car. Works well for rear main seals too...............bob

[Paul Falabella]

Rear end got noisy, found a unit, getting it replaced while it's up, guy will replace torque ball. Looks like that is where it is coming from.

[bhambulldog]

Good news,it's working OK, just need to fix the leak then.

When it stops leaking it means your out of fluid.

Seriously, I've got mine down to three or four drips a week

[Paul Falabella]

Like what they say about English cars, "No fluids under em', no fluids in em'"?

[trimacar]

I've heard that's why the English don't make toasters.....they can't figure out how to make them leak oil....

[trimacar]

In all seriousity, if DC3 (airplane) engines didn't leak oil then there really was a problem....

[Guest Rob McDonald]

[in the] shop manual there is a very good explanation of it's operation complete with colored diagrams explaining motive flow in various configerations

BOB, maybe you could do a English translation of the shop manual's Group 5, "Dynaflow Transmission". I've read it forward, backward, and upside down under water and still can't make sense of how this infernal device does its black magic. BuickMan's description of stuff hitting the fan is about as close as I get to understanding. Which is why I'm dropping mine at a transmission shop on Friday, instead of changing the seals myself.

[Guest shadetree77]

....stuff hitting the fan....

LOL! That's what WOULD happen if I tried to completely rebuild my Dynaflow all by myself. Let us know how the rebuilder treats you Rob. I re-watched a bunch of Mudbone's videos last night trying to prepare myself to replace those front seals. I think I can....I think I can....I think I can.

[buick man]

BOB, maybe you could do a English translation of the shop manual's Group 5, "Dynaflow Transmission". I've read it forward, backward, and upside down under water and still can't make sense of how this infernal device does its black magic. BuickMan's description of stuff hitting the fan is about as close as I get to understanding. Which is why I'm dropping mine at a transmission shop on Friday, instead of changing the seals myself.

All kidding aside Rob, if you go the transmission shop route make damn sure they have a dynaflow satisfaction client list they can hand you that is not over 20 years old. Another tack they take is to call back one of their old employees or the last time one of the guys in the shop who just happens to now be retired can be brought back in to work on your dynaflow. Maybe. Really, I am not kidding here, from my research and foot work I have found probably most present transmission shops have no idea what they are looking at regarding a dynaflow. The gasket set is most likely older than the guy that will be working on your unit. IF you read the manual and can't make sense out of it what makes you think kid wrench is going to be any better? We were talking recently with one of our fellow posters here just in the past couple of months who had just gone through a nightmare experience using the "drop it off" approach. The problem is these days the run of the mill transmission shop does not know what to look for in regards to wear not alone how to have parts re-milled or replaced. Not having this experience and knowledge base can cause a lot of damage to the dynaflow even when doing a simple new gasket run on the transmission. If things are not properly inspected while doing so, there are many potential problems that often arise. Do a search here and you will find the posts to which I refer.

Edited January 16, 2013 by buick man (see edit history)

[Guest Rob McDonald]

DAVID, I sincerely appreciate your concern. If I lived in one of the old car hotbeds of California, the Midwest, or New England, I wouldn't think of taking my Dynaflow to anything but a specialized shop. Sadly, the one guy here in Edmonton, my age, with unquestionable skills and experience with these shiftless transfer cases, has been dead for 20 years now.

Kid Wrench works in a shop that's been owned and operated by the same family for 30 years. Longtime members of the Edmonton Antique Car Club recommended this business to me, as being conscientious and capable of tackling unfamiliar work. The child-mechanic has a long, tidy, stainless steel-clad workbench and every tool he needs within his [tiny] arms' reach. If his boss doesn't have copies, I will loan him my shop manual and parts manual. He will crack open the transmission with the same sense of wonder and curiosity as I would but he won't have my feelings of dread and inadequacy.

I push virtual paper all day long and infrequently get to design steel buildings for faraway industrial mega-projects. Every time I go out to my garage, I must spend 20 minutes shunting things around, to make a few square feet of work space. Kid Wrench, on the other hand, will come into his brightly-lit shop on Monday morning, hang up his parka, mitts, scarves, snow-goggles, and toque, then set to work on my lovely old Dynaflow. If it was properly rebuilt and assembled by his ancestors back in 1973, he could have the job finished by sundown, about 4:47pm these days.

If not, and something really needs fixing, the boy and his boss are far better equipped to do so than me. I'll have had them programme their speed-dial to call Dave Edwards of Auto Tran in Boston. He supplied my gasket set and knows Dynaflows like I know my local Building Code.

This is one of the many hardships of life on the tundra. We are forced by the harshness of nature and isolation to trust each other. Besides, if Kid Wrench really screws up, I have a spare virgin Dynaflow "in the barn".

[Paul Falabella]

"Kid Wrench, on the other hand, will come into his brightly-lit shop on Monday morning, hang up his parka, mitts, scarves, snow-goggles, and toque, then set to work on my lovely old Dynaflow."

What's a toque? Something to do with a Chrysler Gyromatic I'm thinkin'.

[Bhigdog]

BOB, maybe you could do a English translation of the shop manual's Group 5, "Dynaflow Transmission". I've read it forward, backward, and upside down under water and still can't make sense of how this infernal device does its black magic. BuickMan's description of stuff hitting the fan is about as close as I get to understanding. Which is why I'm dropping mine at a transmission shop on Friday, instead of changing the seals myself.

Lets leave it at the paddle wheel analogy, Rob. I could tell you how it REALLY works but then I'd have to have you killed. 8-). BTW, a big hello to the city with the best beef steak in the world..........Bob

[Bhigdog]

DAVID, I sincerely appreciate your concern. If I lived in one of the old car hotbeds of California, the Midwest, or New England, I wouldn't think of taking my Dynaflow to anything but a specialized shop. Sadly, the one guy here in Edmonton, my age, with unquestionable skills and experience with these shiftless transfer cases, has been dead for 20 years now.

Kid Wrench works in a shop that's been owned and operated by the same family for 30 years. Longtime members of the Edmonton Antique Car Club recommended this business to me, as being conscientious and capable of tackling unfamiliar work. The child-mechanic has a long, tidy, stainless steel-clad workbench and every tool he needs within his [tiny] arms' reach. If his boss doesn't have copies, I will loan him my shop manual and parts manual. He will crack open the transmission with the same sense of wonder and curiosity as I would but he won't have my feelings of dread and inadequacy.

I push virtual paper all day long and infrequently get to design steel buildings for faraway industrial mega-projects. Every time I go out to my garage, I must spend 20 minutes shunting things around, to make a few square feet of work space. Kid Wrench, on the other hand, will come into his brightly-lit shop on Monday morning, hang up his parka, mitts, scarves, snow-goggles, and toque, then set to work on my lovely old Dynaflow. If it was properly rebuilt and assembled by his ancestors back in 1973, he could have the job finished by sundown, about 4:47pm these days.

If not, and something really needs fixing, the boy and his boss are far better equipped to do so than me. I'll have had them programme their speed-dial to call Dave Edwards of Auto Tran in Boston. He supplied my gasket set and knows Dynaflows like I know my local Building Code.

This is one of the many hardships of life on the tundra. We are forced by the harshness of nature and isolation to trust each other. Besides, if Kid Wrench really screws up, I have a spare virgin Dynaflow "in the barn".

If your man (Kid) is an experianced trans guy and is at all methodical he will have no problem with your DF. It's an extremely straight forward trans. There are a few special tools needed but nothing that can't be worked around. You are wise to use Dave Edwards as a parts source. Very easy to talk to and always takes the time to help. If your guy follows the rebuild flow as it's laid out in the SM it progresses extremely logically from start to finish.................Bob

[Guest Rob McDonald]

What's a toque?

PAUL, these gentlemen are wearing toques. On their heads.

[Guest Rob McDonald]

the city with the best beef steak in the world

Yep, the very best, washed down with some of the finest beer, too. Rest of the place kind of sucks but, hey, it's still better than Calgary.

Thanks for the vote of confidence in a smart, honest tradesman.

Edited January 17, 2013 by Rob McDonald (see edit history)

[Mudbone]

LOL! That's what WOULD happen if I tried to completely rebuild my Dynaflow all by myself. Let us know how the rebuilder treats you Rob. I re-watched a bunch of Mudbone's videos last night trying to prepare myself to replace those front seals. I think I can....I think I can....I think I can.

The testing I have done is not proof that my Dynaflow will work properly. The pressures were looking ok but there is nothing like driving it to test it properly. One thing I do know is that you may not understand completely how every aspect of the Dynaflow works but you better be darn sure it is put together correctly. Most of these Dynaflows have been apart before so you never know if it was put together correctly last time. (Mine was not) Mud

[buick5563]

Toque= Hoser wear...

[rmartens]

Living on the West Coast it was simply a knit hat or ski hat. My Canadian relatives called it a toque. But moving here to the East Coast (NC) I got real confused when people called them tobbogans. To me that's a 6' snow sled.

[bhambulldog]

We call that hat a toboggan.

Since we only have snow once every two years no-one has a snow sled...

[Bhigdog]

Where I come from "toking up" does not mean putting on a funny looking hat........Bob

[old-tank]

Where I come from "toking up" does not mean putting on a funny looking hat........Bob

:eek:

[avgwarhawk]

Living on the West Coast it was simply a knit hat or ski hat. My Canadian relatives called it a toque. But moving here to the East Coast (NC) I got real confused when people called them tobbogans. To me that's a 6' snow sled.

My mother-in-law(born in Baltimore) called it a tobbogan as well. To me a tobbogan is a sled.

[Paul Falabella]

If I did not like the look of that hat and wished to change it would I need a toque converter?

[buick5563]

If I did not like the look of that hat and wished to change it would I need a toque converter?

Groan.

[Guest Rob McDonald]

This is a very fine toboggan. If you New Englanders want to wear it on your head, that's your weird business. Just remember to warsh it in cold water and dry flat.

Edited January 22, 2013 by Rob McDonald (see edit history)

[Guest shadetree77]

Here's another variation for you. My family always called the hats "boggans". We called sleds "toboggans". When I met my wife, her family called the hats "beanies". No word on what they called the sleds on her side as they have always lived in Georgia where there is no use for a sled. Wow. From Dynaflows to winter hats. I do believe this thread has entered left field gentleman.

[buick5563]

Left field. Camden Yards. Bawlmer Murland. Hon...

Camden Yards section 268 row R seat 6 - Baltimore Orioles vs Boston Red Sox

[Paul Falabella]

Left Field? 10/16/69 Cleon Jones. Davy Johnson. Need I say more?

[Guest kaycee]

..... Gee you did that rebuild when you were only 4 years old? I did'nt do my first overhaul until the age of 10. You are the man! :cool: Or should I say buick boy.

Paul like everyone is saying, think of the Dynaflow as a fluid coupling. Sorta like , you are going down the road due to fluid pressure hitting a fan and the fan flings it and turns it. Come to think of it, like a old water wheel on a river boat.

I said when the car was four years old not me, which makes me? Do'nt remind me. The '55 Century needed a front pump plate from too much racing, and it took me and an old Motors manual a week to do it. 'Not too bad for an eighteen year old with a old roll under jack, huh?

kaycee