63 LeSabre...transmission doesn't kickdown?

[96roadmaster]

Our 63 LeSabre doesn't want to downshift on the 2-1 shift at WOT at any speed. It's a 4 Barrel car (factory option), carb was just rebuilt and is 100%, yet the car won't shift down at any speed. It used to shift down up until a couple months ago. The car has 12k miles on it.

Any ideas anyone can throw at me?

[Pete Phillips]

Please explain how a 2-1 downshift is supposed to occur on a Turbine Drive or Dynaflow transmission. That is news to me. You have enough Dynaflow-equipped Buicks that you must know what you are talking about. I've owned and driven about 20 Dynaflow-equipped Buicks and never heard of a downshift on one of those, other than manually shifting the lever from D to L.

Pete Phillips, BCA #7338

Sherman, Texas

1948 model 71

1949 model 59

1950 model 76-R

1959 Electra 2-dr.

1962 Electra 225 4-dr. ht.

1963 Wildcat conv. 4-spd.

[Centurion]

Pete, I was baffled by the "downshift" comment as well.

Perhaps he means that he's unable to "switch the pitch"!

[96roadmaster]

Well yes, I wasn't thinking straight after a looong day at work yesterday. I know it's not an actual downshift but it's supposed to switch the pitch as Brian mentioned. It feels and sounds like a downshift, exactly like our '58 Super.

The '63 was fine up until a few months ago, now it just tries to pull off from a low rpm and feels like it's stuck "in gear" for a lack of a better term.

Not really an issue either way since I'm not racing it, but I'd just like all features to be working at 100%.

[Guest kaycee]

Hi,

Your Dynaflow trans. does'nt literally shift gears in Drive. If on heavy acceleration you 'floor it', the linkage coming off the carb. towards the firewall and down to the high accumulator on the transmission actuates the stator change in the converter(through oil pressure in the trans.), and it feels like a 'kickdown' or upshift until you let up on the pedal a bit, at which time the stator returns to normal position and it drives as if you just gradually accelerated from a stop but it does'nt 'downshift' and 'drag down' as if you manually downshifted. In Drive without really 'flooring it' you should'nt feel any shifting.

Check the linkage from the rear of the carb.( back by the firewall) down to the transmission to make sure everything is 'hooked up' top and bottom. You can tell by pulling all the way back on the throttle linkage and seeing that it works the rod in front of the firewall going down to the transmision. This linkage should be similar to all Buicks with Dynaflow back to '55 when they came out with the variable pitch stator which gave sort of a 'passing gear'.

If everything is hooked up including the 'bellcrank' on the accumulator on the trans., and you still have a problem, you probably have pressure leakage in the trans. at a gasket or valve body , so good luck.

kaycee

[96roadmaster]

Hi,

Your Dynaflow trans. does'nt literally shift gears in Drive. If on heavy acceleration you 'floor it', the linkage coming off the carb. towards the firewall and down to the high accumulator on the transmission actuates the stator change in the converter(through oil pressure in the trans.), and it feels like a 'kickdown' or upshift until you let up on the pedal a bit, at which time the stator returns to normal position and it drives as if you just gradually accelerated from a stop but it does'nt 'downshift' and 'drag down' as if you manually downshifted. In Drive without really 'flooring it' you should'nt feel any shifting.

Check the linkage from the rear of the carb.( back by the firewall) down to the transmission to make sure everything is 'hooked up' top and bottom. You can tell by pulling all the way back on the throttle linkage and seeing that it works the rod in front of the firewall going down to the transmision. This linkage should be similar to all Buicks with Dynaflow back to '55 when they came out with the variable pitch stator which gave sort of a 'passing gear'.

If everything is hooked up including the 'bellcrank' on the accumulator on the trans., and you still have a problem, you probably have pressure leakage in the trans. at a gasket or valve body , so good luck.

kaycee

Sweet. That's the type of info I was looking for. I'll give it a shot tomorrow. Thank you!!

[Guest kaycee]

Hopefully, you'll just find the linkage off at one end or the other. Again, good luck, and keep us posted.

kaycee

[Patrick91914]

Does the '63 have a vacuum modulator like the '65? If so, the vacuum line may have fallen off.

[Guest kaycee]

Hi,

No, the Dynaflow does'nt have a vacuum modulator like the later Turbo. 400's, starting in '64, and '63 was the last year that Buick had the Dynaflow. Do you have slipping in drive too, or just the problem with the 'passing gear'?

kaycee

[Guest kaycee]

96 Roadmaster,

Hi,

Did you solve the problem with your '63 transmission 'kickdown' problem?

kaycee

[96roadmaster]

I checked out the linkage and all the connections, everything is in place with no slack and it still doesn't kick down. I didn't get a chance to mess with it some more during the week, but I'm about to go pull it out today and give it a last shot.

There is zero slipping in drive. I'm stumped but also a bit frustrated.

[Guest kaycee]

Check for a external leak around the high accummulator cap or a external or internal leak in the gasket where it bolts to the transmission body and make sure that the 'bellcrank'on it is tightened on its shaft before you remove and diassemble anything,. If you have a Motors or Chiltons manual that covers up to '63 and even a few years newer , either will give you all the pictures, troubleshooting, and adjustments for your Dynaflow (Twin Turbine) transmission. With this problem, it may have a sticking ballcheck or a blocked metering orifice in the high accumulator or a bad gasket at the accumulator or the valve body,and you can easily repair it without pulling the transmission out. If not, you may have to check oil pressures which will require the right gauge and running the car on a lift or with the rear end off the ground. Do'nt hesitate to e-mail or phone me if you have any questions or run into a problem.

kaycee

e-mail : littleeight@att.net

Ph:(815)223 3919

[96roadmaster]

Thank you kaycee. I will get on it again this coming weekend. I'll keep you posted of my findings. Hopefully it solves it once and for all.

Thanks again. I'll be in touch with you either way.

[Guest kaycee]

Hi 96 Roadmaster,

'Just curious if you were able to work on your '63, and what you found.

kaycee:)

[96roadmaster]

Hi Kaycee, I just remembered this thread and hopped back on. I got swamped at work and the car has been on the backburner. I tried everything on the outside of the transmission, short of taking off parts and it still does not kick down. I've given up as the kickdown isn't all that important considering the car only gets driven once every 2 months now (and only a couple miles when it does go out).

Therefore, I've officially given up on this one. Maybe I'll get motivated again when things lighten up and I spend more time behind the wheel

[Guest kaycee]

Hi 96 roadmaster,

Thanks for posting again. We'll be around when your caught up enough to 'play with it again'

kaycee

[96roadmaster]

Thanks kaycee! I truly truly appreciate the help. I just wish I had more time to spend on the cars. They've been neglected for a long while.

On the plus side after posting this yesterday I felt bad and pulled out the 84 and tuned the carb (the mechanic had fiddled with it at the last oil change and it was running like crap) and I got it to purr again. I'm going to drive that to work tomorrow just to give it a chance to warm up the fluids.

I'm going to email you in a couple months or so when everything should hopefully quiet down at work and will update you on the '63 puppy.

[Pete Phillips]

With all due respect, I think you can work on a '63 LeSabre transmission until the cows come home, and you will never get what you are after. It doesn't exist! I repeat: A Dynaflow does not kick down. I have owned and driven dozens of Dynaflow equipped Buicks and I have never, never felt one "kick down". Were they all broken? I think not.

If you want a transmission with a kick-down feature, you need to get another make of car. This is crazy, and I'm not going to spend any more time reading or responding to it.

Pete Phillips, BCA #7338

Sherman, TX.

1948 Roadmaster

1949 Super with Dynaflow

1950 Roadmaster with Dynaflow

1959 Electra with Dynaflow

1962 Electra 225 with Dynaflow

Do I make my point?

[Guest kaycee]

Hi Pete,

Take one of your Dynaflow equipped Buicks from '55 through '63 , and 'kick' the pedal down at about 30 mph. The variable pitch stator changes pitch and you get whats similar to a kickdown without any gear change.

I too have had about 20 Dynaflow equipped cars, and rebuilt my first Dynafow on a '55 Century.

kaycee

[NTX5467]

With all due respect, I don't see how you can have a "kick down" or "passing gear" without a real gear change. Yes, the stator will change pitch and increase torque multiplication (and related "stall speed" situation), but NO gear change, as the engine increases in speed a little faster and the vehicle speed similarly increases. It might get there a little quicker, but ONLY due to the torque converter internals doing their thing.

If the transmission's throttle linkage have not been messed with, the adjustments probably are fine. If you suspect something internal might be blocked, there are a few trans fluid cleaner additives (including the GM Automatic Transmission Conditioner) that might free and clean things up prior to a fluid change, plus make some of the rubber seals a little softer. The service manuals (referenced) will provide "line pressure" at particular road speeds, which can be a way of diagnosing what's going on inside the trans, but are usually more indicative of the correctness of the linkage adjustments (typically).

The change of stator angle lets the engine rev up a little more freely, with appropriate increased throttle input, but no "kick down feel" unless the 4bbl might also chose to start cracking open at the lower engine speed . . . IF it has a 4bbl.

Regards,

NTX5467

[Guest kaycee]

I know how a Dynaflow operates . From my fifty years experience on Buicks and Dynaflows, as I said before there is No gear change in drive. However, even with a 2bbl carb in a LeSabre (or earlier Special back to '55) there is ( according to the Buick shop manuals and Motors manuals) the " equivalent of a passing gear" with the variable pitch stator in the converter with no gear change. You can definately feel what seems like an mild upshift in drive on heavy acceleration in drive, but you wo'nt feel a downshift when letting up on the pedal.

kaycee

[NTX5467]

I realize that we're playing a "war of words" here, but an important one such that EVERYBODY understands that "no gear change" results in a DynaFlow (under the described driving conditions), unlike other step-gear transmissions which have an automatic gear downshift to a lower gear at lower road speeds and heavy throttle input.

Not unlike many customers perceiving a "gear change" when 1980s lock-up torque converters did their thing, or when the fan clutch on a GM 454 C-30 would cycle while pulling trailers in hot summer weather--sensory input leads the customer to suspect one thing is happening when it's something else instead. Or a perceived lack of WOT power for some throttle-body fuel injected engines compared to the prior QuadraJet 4bbl versions where customers didn't get that "4 bbl feel" at WOT, no feel = no power, although the engines had similar horsepower ratings.

Kaycee, Pete, myself, and some others might understand what's going on in a DynaFlow, but WE also need to make sure that others do too, even if it might require some extra explanation of why particular terms are NOT correct with respect to the way a DynaFlow operates, compared to other step-gear automatic transmissions. The quote from the Buick service manual is correct and accurate and a good explanation of the situation. From my examples above, what one might "feel" can be different from what's actually happening mechanically.

Enjoy!

NTX5467

[Guest kaycee]

Well put exactly, NTX5467! Thanks for your and others input!

The original poster on this problem? ( 96roadmaster) has two '58s and a'59, so I would think he should be able to tell if something is different about the transmission operation of his '63 from the other three Buicks unless his other cars are Flightpitch which would have a grade retarder feature. At going back to his original post, I noted that he mentioned "no 2 to 1 downshift" which does'nt occur on a Dynaflow period.

Hopefully he'll get back to us or have someone in his area that's familiar with how Dynaflows drive take his car out and drive it to see if there is a problem.

kaycee

[96roadmaster]

NTX, thank you for your explanation. That's EXACTLY what I was thinking about but wasn't sure how to describe it. I know it's not an actual gear change (same as the other Dynaflow cars we have), but it "feels" like a downshift. So to make it easier to spell it out, I call it a downshift.

The Dynaflow in the 58 Super has always worked perfectly and I use that as my "model" to compare the others to. The 59 225 had a similar thing where it would not "downshift" at full throttle, and it was diagnosed to the carb. After a rebuild it's been working great.

I hopefully would have some free time away from work in month or so and am going to tackle this one again. It's not a huge deal, but it's jsut for the sake of knowing everything is 100%.

kaycee, once again, a huge thank you for all your help. I will keep you updated along the way!