Jump to content

Recommended Posts

Posted

OK, I am showing my ignorance again. I have a 63 Riviera and when I got it I was told that the transmission was rebuilt, but whoever did it messed up because it will not shift out of first. I don't know much about dynaflows and neither did the woman I bought the car from. Her and her husband had numerous 64's and 65's, but this was thier first 63. From what I have read, the dynaflow is a totally different animal than a TH-400. I believe someone mentioned that it does not shift the same way. Can some one tell me how it is supposed to operate normally so I can figure out if it is functioning properly? Right now I can't get it up to speed because it has no brakes, but when I have moved it in the past, it throws you back in the seat in a big hurry.

Carl

Posted

I to have a dynaflow in my 63... This transmission is the smoothest thing I have ever driven.

The reason for that is it does not shift gears. The transmission converts engine power into useable torque by adjusting vanes operating in fluid to increase or decrease pressure and regulate output.

basically its a jet engine that operates in transmission fluid, I guess thats why they call these transmissions a super turbine. The only thing they need is to keep trans-fluid at the required operating level and you won't feel a thing... ever! The drawback is that they lack the ability to do those long smoke burnouts my '64 Riv could do. I have also noticed they have a tendancy to leak

but I will gladly top up fluid in exchange for the silky smooth drive it provides.

As a side note on the dynaflow... Toyota and Honda now use a similar design, although computer controlled on their high-end cars.

John

Posted

Carl,

You can do those long smoky burnouts by putting the dynaflow into the low gear. BUT, DO NOT shift from low to drive under full throttle, all sorts of nasty things can happen. Low gear in a dynaflow is not like a low gear in a TH400. The chassis manual for 1963 says the only thing that low is to be used for is trying to rock your way out of loose sand or snow or anyother time you're stuck. John is correct, there's nothing like the smoothness of a "Twin Turbine" dynaflow. (They started with the name Super Turbine in 1964 when the switched to the TH400 - ST400 was Buicks name for the same transmission.) Because the whole thing is fluid drive, there is inherently some loss of effeciency with them. More than the ST400 and way more than a modern trans with a lock up torque converter. There's also a difference in the crankshaft of the 63 401/425 and the 64, 65, 66 401/425. The difference is in the hub on the crank where it bolts to the flexplate. ST400's are not a drop in type of swap for a dynalflow.

One other thing you might be glad to know. You can push start a car that has a dynaflow in it. The car being pushed/pulled needs to take off in N until the speed reaches 35 mph. At that point pull the lever into D and the engine will turn over and you can start it. Says so right in the chassis manual.

Ed

Guest Rivdane
Posted

<div class="ubbcode-block"><div class="ubbcode-header">Quote:</div><div class="ubbcode-body">One other thing you might be glad to know. You can push start a car that has a dynaflow in it. The car being pushed/pulled needs to take off in N until the speed reaches 35 mph. At that point pull the lever into D and the engine will turn over and you can start it. Says so right in the chassis manual.

</div></div>

And it works, I have tried it on a 1958 Limited 4 dr. We pulled it with an old VW Golf diesel, it almost killed the VW, but we got the Limited started.

I have got a dynaflow in my 61 Electra 225 Convertible and several people here in DK has asked me why I dont put another gearbox in it (poor gasmileage bla, bla)?. Why should I, it is the ultimate gearbox for a cruiser !!!!

and is that not, what these classic cars are all about? Lean back, light tap on the speeder and enjoy the ride.

Posted

Brian,

Great comments. I too like the "non" feel of the dynaflow. I know the gas mileage sucks and it's an inefficient transmission, but when needed, the car can still do 120 mph without whimpering. I have thought of looking into the possibility of adding a Gear Vendors overdrive unit to it, but haven't researched it yet. Anyone you know of done anything like this?

Ed

Guest Rivdane
Posted

That sounds very interesting, but I dont know of anyone, who tried anything like that. Just finding someone who knows how to repair a dynaflow is a problem in Denmark. But there is hope !!!!, there is a lot of classic UScars going to Denmark these years, and a good portion of them are Buick´s (I´m doing what I can to get more Buick´s to Denmark). I have talked with a transmission repairshop and they know a little about the dynaflow and have started to do some research to improve themself. We cant let one of the smoothest automatic transmissions ever made die in Denmark, just because of lack of knowledge.

Posted

Brian,

A video of that Golf pull or push starting the 58 Buick would be priceless! Must have looked like an Ocean Liner and a Tug Boat! There is a very good explaination and service procedures for the Dyna Flow in the 1963 Buick service manual. Parts are available on ebay and in some of the vendor's stores as well. I've got two of the darn things in my garage plus two more in my 63 Rivs, but also have 2 replacement 4L60's ready to go at work! If my Dyna Flows ever fail, it'll be a big decision to make on which way to go!

Take Care,

Tim

Posted

Uhm, 35 mph is going pretty fast to 'jump start' a Dynaflow equipped vehicle. There are too many variables involved to contemplate, IMO. If you have a hill, the hill still needs to long enough, then there are the possible hazards and the fact that in some cases, a non routinely started vehicle will still die if not in tune. I can't believe Buick put that in the shop manual/owners manual. The stick shifts I used to own or work on? 5-15mph, pop the clutch and go. 35 mph is higher then the speed limit in most suburbs.

Posted

Jake,

You seem to not quite understand the issue. The Dyna Flow, along with many other early automatics had a provision built into them for push starting the car. The reason for this was 6 volt electrical systems, weak ignition systems and marginal batteries. In colder climates, it was not uncommon for a properly tuned engine just to refuse to start in sub-zero temperatures. That is why these early automatics had two transmission pumps, one front and one rear. The rear pump was smaller and had less capacity than the front pump, but it turned anytime the drive shaft turned. At 35 mph in was capable of producing enough pressurized fluid to allow the torque converter to turn the engine over. Below 35 mph, there was not enough pressure to hydralically activate the converter. With the key in the "ON" position, power would be supplied to the ignition system and when the driver pulled the transmission into Drive or Low, (transmission dependant) the engine would turn over and hopefully start. Granted, this was in the day before lawyers owned the world and common sense was a lot more common! Hope this clears up some of the reasoning at the time!

Tim

Posted

Tim,

Thanks for that clarification. It made me laugh. It does make more sense now.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...