What did I blow up in my 727?

[MOPAR MARTY]

This past Saturday night I was out with a buddy of mine and his 70 Charger R/T and we were messing around on some back roads. He accelerated, and I followed suit and as I was accelerating, I was overcome by stupidity, and downshifted from D to 1 (with my 727). For a split second, the car accelerated then a loud bang and no more going. I gave the car some gas but it just continued coasting; had nothing in D, 2 or 1. Got to the side of the road and started looking. There was no fluid pouring out, fluid was still red and saw no metal shavings on dipstick. While being tow strapped to my buddy's house, a whining noise could be heard in N. Car still moves in R. And this is a 727 built by a reputable Mopar transmission guy, so kind of sad this happened. Really hope that whatever is blown up, it's not the GearVendor OD.

Learning my lesson never again to downshift from D to 1 while accelerating, I'm assuming I need to drop the trans and have it rebuilt, as it's probably more complicated than just the valve body or something accessible with the pan off.

I'm doing my learning now, so what most likely did I blow up?

i use to take my built 400 in my 73 polara to lower gear @ 45 all the time took it up to 6000 rpms &S hit 2nd thrn up to 5800 & hit drive (that was 115 mph ) all the time. now maybe i was lucky . what rpms was u turning when u pulled it to 1?

 

[440beep]

Unfortunately I wasn't looking; too busy watching the road and making sure I was straight before I nailed it. I was probably doing 40-45mph with a 4:10 gear, so maybe 3K or so.

i use to take my built 400 in my 73 polara to lower gear @ 45 all the time took it up to 6000 rpms &S hit 2nd thrn up to 5800 & hit drive (that was 115 mph ) all the time. now maybe i was lucky . what rpms was u turning when u pulled it to 1?

 

[Fury Man Van]

The Bee is up in the air, and dropping the trans/Gearvendor tonight. Though I still need to run out and buy another jack for tonight, one jack to support the motor, and one to lower the transmission. Also needed higher jack stands, so I searched the posts here, and picked up 2 sets of the US Jack 6-ton stands and being very close to Benton Harbor, MI, the jack stands were here in a day. As someone said in one of the posts, "how valuable is your life?" There's always a part of me that is hesitant getting under a car even with the wheels on.

Luckily I'm very close to Keith Long (727specialist.com) who will be doing THIS rebuild. After learning about the Griner valve body, I'm very interested to see if I notice any difference in the shifting.

View attachment 1174917 View attachment 1174918

What style of wheels are those, they look sharp.

 

[Fran Blacker]

Any news what busted?

 

[440beep]

Billet Specialties 5 spoke with black highlights. The back wheels are 10" with 295 tires on them. I can pick the entire thing up with one arm. Nice and lightweight.

What style of wheels are those, they look sharp.

 

[440beep]

No, not yet. Keith has a three week back log and I dropped it off with him last Tuesday, 10/5. Just from talking with him, like others here, he's thinking maybe the front planetary gears, or maybe even a clip got sheared off.

LOLOL - he said he will save me the parts to put on the "wall of shame" in the garage. Maybe I will make a shadow box for the parts, and put it by the driver's door as a reminder every time I get in the Bee NOT to downshift from D to 1 while doing 40+mph.

Any news what busted?

 

[Fran Blacker]

Got a few reminder pieces my self. Broke a brass cooler fitting on a trans. The piece I removed is still on the ez-out. It's 30+ years ago.

 

[Fury Man Van]

Billet Specialties 5 spoke with black highlights. The back wheels are 10" with 295 tires on them. I can pick the entire thing up with one arm. Nice and lightweight.

Those are sweet I love them

 

[440beep]

Here's a better pic.

Those are sweet I love them

 

[Van Stahr]

I dropped mine in low leaving a stop light and bang. The sprag and a few other items were toast. I think that was the last straw because it has some issue for months before that.

 

[Fury Man Van]

Here's a better pic.

Those look very similar to these Mirada wheels that I have on my 68 4spd convertible

View attachment 1178635

 

[440beep]

Keith (727specialist.com), phoned me yesterday and like several members here thought, the front planetary gear pack was stripped, and everything else looked good. He is going to replace a lot of parts, and swap out the valve body of his own making instead of reworking someone else's product.

 

[440beep]

Picked up the "new" transmission and pieces last night from Keith. Almost everything inside was replaced, he has his way, and others have their ways. He used his valve body with his "tricks" versus working with someone else's. But here's pictures of the stripped front planetary pack with shrapnel shards still on it; didn't even know it was a 4 gear one.

 

[AR67GTX]

That’s kind of discerning - how much hp is your engine making? I’ve always found these torqueflites to be really tough - I abused the one in my 64 Sport Fury as a kid for years - pulling full throttle auto downshifts to first at nearly 40 mph more times than I can count. But I guess the little old 383 Commando didn’t have enough guts for that kind of carnage. Good to see you got it all fixed up, better than before.

 

[440beep]

The Bee makes 600 at the crank. And curious if the 4:10 gear amplified things? But I learned my lesson, no more D to 1 downshifts when doing 40mph.

Transmission is in, and hopefully I get all the misc pieces and parts installed by Sunday so I can take her out. Dying to see how she drives now! Trans guy said it should be noticeable difference. "just don't beat on it the first time out, let the trans absorb the fluid, let her soak it up overnight, then the next day you should be good to burn."

That’s kind of discerning - how much hp is your engine making? I’ve always found these torqueflites to be really tough - I abused the one in my 64 Sport Fury as a kid for years - pulling full throttle auto downshifts to first at nearly 40 mph more times than I can count. But I guess the little old 383 Commando didn’t have enough guts for that kind of carnage. Good to see you got it all fixed up, better than before.

 

[AR67GTX]

Yeah, that’s a lot of HP. Hope all is good now.

 

[Fran Blacker]

Can you go 40mph in low gear with 4.10's, rpms must be up there. Go D to low the rpms would be tough to match. Had a manual VB in my car put in low engine would free rev until engine and speed matched. Didn't do that on purpose more than a few times. Live and learn. Burned up 3 transmissions in a 64 Olds I was a slow learner. Those were notorious lousy trans but I didn't know it.

 

[1 Wild R/T]

Gotta wonder if either the planetary or the output shaft was changed when the trans was built last time it was apart.... They changed the angle of the splines in the 75-76 time frame & while the parts will fit together the angle being wrong causes the splines in the planetary to fail over time...

 

[440beep]

Hmmmm, I will have to try that, usually I'm just creeping in L, but will have to try and see if I can get to 40mph and how much the motor is screaming.

Can you go 40mph in low gear with 4.10's, rpms must be up there. Go D to low the rpms would be tough to match. Had a manual VB in my car put in low engine would free rev until engine and speed matched. Didn't do that on purpose more than a few times. Live and learn. Burned up 3 transmissions in a 64 Olds I was a slow learner. Those were notorious lousy trans but I didn't know it.

 

[440beep]

The transmission was originally a Coan, and that didn't last the summer and it was not my driving. Second Mopar transmission specialist said the Coan parts were questionable and he rebuilt it. No idea, 1st or 2nd guy, who put in the planetary or output shaft. The 2nd guy really touts himself as "Mr 727" and I would hope he knows all the part differences.

But in any event, I'm on my third builder now, and all my Mopar buddies swear by this guy.

Gotta wonder if either the planetary or the output shaft was changed when the trans was built last time it was apart.... They changed the angle of the splines in the 75-76 time frame & while the parts will fit together the angle being wrong causes the splines in the planetary to fail over time...