Story by Phil

“Great care was taken to achieve a smooth shifting transmission. We weren’t sad to see the Dynaflow and Dual path go…”

Around late 1963 Buick Motor Division took over the GM Hydromatic division. Their first project was to be the Turbo Hydromatic 400 three-speed transmission. It came out in the upper series Buicks in 1964. They also developed the Turbo Hyrdomatic 300 two speed for the lower series. Engines were developing more horsepower and the days of the fluid drive Dynaflow were gone.

Great care was taken to achieve a smooth shifting transmission. We weren’t sad to see the Dynaflow and Dual path go. The Dynaflow had a cast iron case, was almost as heavy as the engine and not easy to remove. The air-cooled Dual path would overheat in city driving. The two new transmissions had an aluminum case and weighted a lot less than iron. The 1964 ’65 and ’66 models had a switch pitch torque converter and an anti creep feature.

Two electric switches on the throttle linkage controlled these. The one adjacent to the carburetor controlled the variable pitch torque converter. A high stall speed from the converter gave you a great take off from a stop and a low stall speed gave better fuel mileage with lower engine rpms. A second switch was mounted up by the firewall on the vertical throttle rod. This controlled the anti creep feature. At idle it would reduce the oil pump pressure in the transmission. The idea was you could remove your foot from the brake while the trans was in gear and the car would not move.

1967 would be the last year for the THM 300 to be replaced by the THM 350 again designed by Buick. Both the THM 400 and 350 would be the most common transmissions used in GM cars and trucks for years to come. The THM 400 was the favorite choice for the racing enthusiasts and was considered the strongest transmission available for a long time.

In 1971 the Rivera was the first GM car to use the integrated voltage regulator. Internal inside the alternator was this little circuit board taking the place of the box mounted on the firewall. It was later used on all GM cars and trucks.

The 1974 Buick had a dual air bag option on the Rivera and Electra – we sold one of each. The mechanics were cautioned to disable the system before electrical work. Should the bags deploy it would total the car. Cost of repair exceeded the price of car. Also in 1974 the high-energy ignition system known as HEI was an option on both the 455 and 350 engines. It became standard on all 1975 and later GM cars and trucks.

1977 brought rear disc brakes to the Rivera. This was a Delco Moraine system with a single piston. The disc system was also the parking brake unlike the 1963 Bendix system used on the Corvette with the four-piston caliper. Cadillac also used this system.

1978 Skyhawk late production had what was called at the time a C-4 system. An on board computer controlled the fuel mixture and ignition timing. The system became an option on the 1979 V-6 Regal and optional on all 1980 GM cars. In 1981 it was standard equipment on all GM cars and renamed the CCC system. CCC stands for Computer Controlled Combustion.

1978 a turbocharger was available on the V-6 Regal. It increased horsepower from 105 to 165.

1979 the Riviera went to front wheel drive. This wasn’t a first because it was basically a copy of the 1966 Oldsmobile Toronado. This was not a transverse engine. The engine was like a rear wheel drive car with a transmission that made a U turn to a front differential.

The 1986 Riviera was a nightmare. A 9 inch CRT on the dash made by Zenith. This little television screen controlled the heater-A/C, radio and information display. To make matters worse it had five on board computers. It stayed this way thru 1989 and drove the mechanics nuts. Buick was the only one with the CRT, big mistake!

1991 a supercharged V-6 came out in the Park Avenue Ultra. It was not a racecar but impressive for what it was.

Phil