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727 Fatal oem design flaw disappointment

70rcode

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Although misleadingly distracted bolster by external factory oem driveshaft & Dana axle over-build rating & appearance but No dealer garage, instruction book or dash sticker warnings cautions, i made hundreds of youthful seeming safe "slap-stick" 1st gear burnout launches & down shift gear drops totally unadvised & unaware of the Hidden, weakly installed, cheap flimsy tin metal sprague & powdered potmetal massive exploding drum personal injury & total vehicle destruction potential...Now, if I reasonably value my only 2 healthy feet, legs, sack & other vitals + unreplacable #'s match treasure, I've Got to $pend more big bucks on a needless 2nd rebuild just 'cause Chrysler knowingly installed a weak designed & implimented POS between their hi-perf forged Steel crank & expensive (for me) $uper track pack Dana60 option package ! ..... really ticked off........tom.
 
Shouldn't have had to do a second rebuild, That weakness has been known for decades. That is a good reason to use a professional Mopar transmission builder. Like any other component on your car , there are always compromises and improvements done as time goes on. You pay for their expertise and experience in these type of things.
 
We used transmission blankets in the day, and didn't give a crap. Junk yard transmissions 30-50 bucks then. Engines 100-125 and we are racing the next day. It's a wonder that we find matching numbers machines today. If you are going to play, pull your matching numbers stuff and go with a play engine and transmission. I have a 400 based 451 stroker, and Hughes built transmission in my 68 Dart GTS. The matching 383 engine is tucked safely away. I never had the matching transmission so that is that.
20171109_094355.jpg
 
Hidden, weakly installed, cheap flimsy tin metal sprague & powdered potmetal massive exploding drum personal injury & total vehicle destruction potential...
While there have been some troubles with the sprag, if you've managed "hundreds of youthful seeming safe "slap-stick" 1st gear burnout launches & down shift gear drops" then it seems that Chrysler engineered it sufficiently sturdy enough for normal driving.
 
Oh man, used to do neutral drops then while rolling forward hit reverse and do a 'Jay' turn and hit drive and never let up off the throttle! Had a 79 D150 SWB that got a 360 Super Coupe engine dropped into and I was just royally brutal to that truck. Never did a J turn with it but did just about everything else with it plus dragged raced it and pulled my race to the track once I got one. My 4 speed cars were actually treated much better.....except for full throttle power shifts :D
 
Now, if I reasonably value my only 2 healthy feet, legs, sack & other vitals + unreplacable #'s match treasure, I've Got to $pend more big bucks on a needless 2nd rebuild.

There's an old adage about "doing it wrong and getting away with it or doing it right". I too, in my youth, unknowingly did all the no-no's with the TF and somehow survived unscathed.
 
Well the original Torqueflight transmission design came out in 1956. Over the years, not that many changes to the original design until I think the mid 1980's when they went to the lockup converters, and even then, that was a fairly minor change. Then it was the basis for the 4-speed overdrive 518 up to the 48RE version in the mid 2000's Diesel trucks. Just saying the basic design and components stayed in production for about 50 years, so it was not that bad.
Back in 1970 cars usually did not have any warnings or cautions. Heck, seat belts were not even required in a car until 1968.
The transmissions are pretty durable in stock form for the standard vehicle and driver. Usually the entire drivetrain of transmission, Driveshaft, and rear axle can handle around 500+ HP. The sprag and direct drum are two parts normally replaced in race transmissions, and a good safety item to have in any torqueflight.
On the sprag, there are the factory 12-roller design and the replacement "bolt-in"s, but the inexpensive bolt-in sprags are the 12-roller design like stock, and are just a repair part if the original sprag was loose in the case. The A&A, and Coan "Ultimate sprags" aur the upgrades overstock and have 16 rollers in them.
 
If I had a car that was going to see mainly track use, I would definitely invest in a billet steel front drum and bolt-in overrunning clutch. JMO
 
Well the original Torqueflight transmission design came out in 1956. Over the years, not that many changes to the original design until I think the mid 1980's when they went to the lockup converters, and even then, that was a fairly minor change. Then it was the basis for the 4-speed overdrive 518 up to the 48RE version in the mid 2000's Diesel trucks. Just saying the basic design and components stayed in production for about 50 years, so it was not that bad.
Back in 1970 cars usually did not have any warnings or cautions. Heck, seat belts were not even required in a car until 1968.
The transmissions are pretty durable in stock form for the standard vehicle and driver. Usually the entire drivetrain of transmission, Driveshaft, and rear axle can handle around 500+ HP. The sprag and direct drum are two parts normally replaced in race transmissions, and a good safety item to have in any torqueflight.
On the sprag, there are the factory 12-roller design and the replacement "bolt-in"s, but the inexpensive bolt-in sprags are the 12-roller design like stock, and are just a repair part if the original sprag was loose in the case. The A&A, and Coan "Ultimate sprags" aur the upgrades overstock and have 16 rollers in them.
In 56 they were called Powerflites and had a cast iron case?? I remember dad bought a 56 Plymouth Belvedere Sports Coupe and had the 'Powerflite' emblem on the lower right side of the deck lid and iirc it was how it was speeeled.
 
I ran the '71 Charger for years street/strip, 4,150 pound car, 12.5 @110 MPH ET (bandimere) with the 727 torqueflight, all stock internals including the stock tan/brown type frictions and stock bands. The only modifications were a Dynamic 10" converter, TF-2 Shift Kit, and an extra trans cooler.
Took it to MATS (Vegas) one year and ran 11.80@115 MPH off the trailer. That nice low 2,000 ft altitude, compared to Bandimere 5280 altitude. I didn't have any transmission failures at all, but when I went to freshen and upgrade the transmission for the new engine (100+ more HP than the old one), the front planetary gear splines were cracked and a few fell out, so upgraded to a steel spline front gear along with the Bullet drum, Super Sprag, and better frictions, steels, and bands
 
Well in 1965 GM came out with the TH-400, so it is a newer design by 9 years? They can explode too.
Of muscle car transmissions for FORD, I guess Fords C-6 (1966)?
 
Those sprag's were used in many applications. International tractors used them in their Torque Amplifiers. They were called TA's and had a sprag that would go out.
 
I'm perhaps not gathering all posted; but I stopped doing neutral drops 40 years ago. Never did a slam into R trick...just didn't seem a good idea on a stock trans. I've followed some advice I got eons ago that it wasn't a good ploy either to drop the trans into lower gear at high speeds. Can upshift it manually all day if you find it thrilling and do this occasionally with my PB '63 727 Plymouth - then there's a manual VB setup. I'd not find this tolerable for long street driving. Installed a shift kit some years ago for a tad firmer shift. I don't know, just seems a risk beating the crap out of a stock trans much as the TF has been legendary for durability and preferred by some of the drag racing greats back in the day. I'm old now though and big burnouts isn't what I long for anymore but to each their own.
 
Although misleadingly distracted bolster by external factory oem driveshaft & Dana axle over-build rating & appearance but No dealer garage, instruction book or dash sticker warnings cautions, i made hundreds of youthful seeming safe "slap-stick" 1st gear burnout launches & down shift gear drops totally unadvised & unaware of the Hidden, weakly installed, cheap flimsy tin metal sprague & powdered potmetal massive exploding drum personal injury & total vehicle destruction potential...Now, if I reasonably value my only 2 healthy feet, legs, sack & other vitals + unreplacable #'s match treasure,

Yet here you still are, along with the rest of us with two feet still intact.

Please list all of the catastrophic failures that you personally know about with unmodified factory cars. Of course, hot rodders have been upgrading trannys for this condition for over 40 years.
 
Tom, you are trolling right?? 56 years, im still counting two legs, two nuts, etc. Build 'em right, for the purpose, and play on!
 
Hell yeah vent....very inexperienced poboy kid racing '70-75..every $1into it..pro trans shop built 727 & No gernade mentioned...just a "no 1st burnout" bad for trans note...11.0's 125 not bad at time. Had No idea that Carnage could happen 'till 'bout '95 when saw one gernade bad thru Nhra cert'd shields (broke u-joint buzz'd rpm)..I'm sure Dodge aware by '63 & coulda simple factory Fixed...& that's the rub...trusted the good factory crank & Dana not knowing They know I'm belted over a bomb They coulda fixed !
 
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