NOS Transmission

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SUBURBAN5

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Schurkey

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IF it's genuine, and IF they find the right buyer, lots of money could change hands.

If it's some old core in an equally-old box, it's a piece of crap. Potatoglides were a crap transmission when they were new. The idea is that two gears plus a torque converter is supposedly equal to a three-speed manual. Well, yeah, sort-of. On the street, paired with typical high-production "street" engines--four and six poppers, small-block V-8s--they're a total turd.

They're a fine racing transmission if built properly, and used in the right application (big power, light weight vehicle.)

Otherwise, they're a black mark on GM's reputation. Should have been discontinued at the end of the cast-iron era, in favor of a Torqueflite-style 3-speed instead of being revised with an aluminum case and still missing a proper low gear.

What Chrysler did right was two-pronged: Not only did they build a fantastic transmission in the 727, but they scaled it down to make a fabulous transmission of similar construction for lower-power vehicles in the 904.

GM actually built a better/more sophisticated trans in the mighty TH400 and variants, but they did a total redesign instead of scaling-down the 400 to create the TH350. (The TH350 was really a Buick/Chevrolet joint project, and many were actually built by Buick.)

GM wasted a lot of time, money, effort, and enthusiasm between the Dual-Coupling Hydramatic and the Turbo-Hydramatic 400, with the aluminum Powerglide, the Super Turbine 300 (both 2-speed transmissions) Turboglide, and the two Slim Jims (Roto-Hydramatic)

I don't know how I feel about the Buick Dynaflow and Turboglide "torque converter CVT" transmissions. Turboglide was kept in production 'cause otherwise they'd have to admit it was a disaster. The latest version of the Dynaflow family was essentially a Buick version of the Turboglide--A three-ratio "automatic" transmission where power could be fed hydraulically into two or even all three ratios at the same time. Interesting if not enormously successful. The last few years of Dynaflow-family production went back to the previous design, re-named and with typical model-year improvements, and was quite successful in it's intended mission--an absolutely smooth trans with no perceptible shifts. Buick (and Chevrolet) used a completely crap-tastic rear suspension that was both enormously heavy, and tended to transmit noise/vibration/harshness to the vehicle passenger compartment (torque-tube rear axle.) As a result, a "shifting" transmission would have unacceptable NVH as it shifted. So "non-shifting" torque converter CVT trans were invented in the Dynaflow and the first few years of Potatoglide production.

I STRONGLY recommend anyone interested in transmission theory and production history to look up Ate Up With Motor's "Technology" section, with links to multiple articles on GM/Chrysler/Studebaker/Borg-Warner/Packard/Rolls-Royce/Ford transmission designs.
www.ateupwithmotor.com/terms-technology/

 
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Caman96

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Just a cool time capsule, nothing I’m interested in buying. I had a 727 in my ‘69 340 GTS Dart and it definitely could take a beating.
 
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