Holy Crap!

AJ77

Well-known member
Joined
Oct 10, 2008
Messages
278
Location
Azle, Tx.
The wife and I went out for a beer or two Friday evening and on the way home I felt froggy and decided to have a little fun. I turned onto the farm to market road going to my house and jumped in it. I shifted into 4th @ 110 mph and I backed out of the gas. We drove about another 3/4 mile to the driveway and when I turned in I could hear the driveshaft hitting the tunnel. I told her I probably just broke the trans mount, no big deal. It would take me about 30 min to fix. The next morning I jacked the car up and found the trans housing was broken completely in half right in front of where it forms the bellhousing. Cool huh?
 
I've got some pics of the damage if our prude IT department will let me load them. Actually, I'm planning on driving the car to a crawfish boil on Friday. I dropped the trans off at the shop that built it (Phoenix Trans.) this morning and they said it will be ready by Thursday at no charge to me. They are going to warranty it!! They are even going to use a case from a 4x4 cause the bellhousing area is stronger. They did say if it happens again, they will have to look at my car to see WTF. That's customer service.:thumbs:
As for the mounts---motor and trans are poly.
 
What kind of tranny WAS that?? all the bellhousing bolts secure??

without a converter blasting it, I never seen one do that....

:crap::(:suicide:
 
nothing a little jbweld won't fix :D

Yeah, I thought about getting out the tig but they are honoring the warranty. Gene-it is a 700R-4 and yes the bellhousing bolts were tight. I figure it had a hairline crack that just got missed at the time of rebuild. There's no way my motor has the torque to do that! They are going back with a case from a 4x4. The mounting area and bottom flange where the dust cover goes is about half again as thick as the pass car one. One thing good is that when the driveshaft beat the crap out of the tunnel it gave me a little more clearance.:lol:Art
 
nothing a little jbweld won't fix :D

Yeah, I thought about getting out the tig but they are honoring the warranty. Gene-it is a 700R-4 and yes the bellhousing bolts were tight. I figure it had a hairline crack that just got missed at the time of rebuild. There's no way my motor has the torque to do that! They are going back with a case from a 4x4. The mounting area and bottom flange where the dust cover goes is about half again as thick as the pass car one. One thing good is that when the driveshaft beat the crap out of the tunnel it gave me a little more clearance.:lol:Art

That's what mine is. A truck case. FWIW, I would also ditch the poly trans mount, and use rubber there. Poly puts too much stress on the tranny mount.
 
nothing a little jbweld won't fix :D

Yeah, I thought about getting out the tig but they are honoring the warranty. Gene-it is a 700R-4 and yes the bellhousing bolts were tight. I figure it had a hairline crack that just got missed at the time of rebuild. There's no way my motor has the torque to do that! They are going back with a case from a 4x4. The mounting area and bottom flange where the dust cover goes is about half again as thick as the pass car one. One thing good is that when the driveshaft beat the crap out of the tunnel it gave me a little more clearance.:lol:Art

That's what mine is. A truck case. FWIW, I would also ditch the poly trans mount, and use rubber there. Poly puts too much stress on the tranny mount.

I don't care for Poly for engine OR tranny mounts......i'ts only a 350, but the Pontiac guys with good cube engines used to put a torque chain/cable on their cars....:hunter:
 
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I don't care for Poly for engine OR tranny mounts......i'ts only a 350, but the Pontiac guys with good cube engines used to put a torque chain/cable on their cars....:hunter:

Gotta agree with Bird and Gene on their comments.
It's well known that these frames flex a lot when you hit a pothole, or turn into a offset driveway or road, and the powertrain is not designed to function as a five foot long torsion bar.
FWIW, I run rubber mounts at all three locations in my '69. If engine torque was the reason rubber mounts broke, I'd have gone through dozens of them over the years.
 
The thread title says it all, holy crap! I've never seen anything like this, I'm glad they fix it for you.
 
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I don't care for Poly for engine OR tranny mounts......i'ts only a 350, but the Pontiac guys with good cube engines used to put a torque chain/cable on their cars....:hunter:

Gotta agree with Bird and Gene on their comments.
It's well known that these frames flex a lot when you hit a pothole, or turn into a offset driveway or road, and the powertrain is not designed to function as a five foot long torsion bar.
FWIW, I run rubber mounts at all three locations in my '69. If engine torque was the reason rubber mounts broke, I'd have gone through dozens of them over the years.

Yea, I might switch to rubber. The guys at Phoenix Trans said they have never had a problem with poly except when there is a poly trans mount and rubber on the engine. I've already got a new rubber trans mount on the shelf at home, so not much more to get rubber for the engine, just a bit of a PITA to do the switch. As for the poly making the trans too rigid, if you saw how much the Bowtie crossmember flexes when the engine is running, you can clearly see the strain is all on the motor mounts.
 
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I don't care for Poly for engine OR tranny mounts......i'ts only a 350, but the Pontiac guys with good cube engines used to put a torque chain/cable on their cars....:hunter:

Gotta agree with Bird and Gene on their comments.
It's well known that these frames flex a lot when you hit a pothole, or turn into a offset driveway or road, and the powertrain is not designed to function as a five foot long torsion bar.
FWIW, I run rubber mounts at all three locations in my '69. If engine torque was the reason rubber mounts broke, I'd have gone through dozens of them over the years.

Yea, I might switch to rubber. The guys at Phoenix Trans said they have never had a problem with poly except when there is a poly trans mount and rubber on the engine. I've already got a new rubber trans mount on the shelf at home, so not much more to get rubber for the engine, just a bit of a PITA to do the switch. As for the poly making the trans too rigid, if you saw how much the Bowtie crossmember flexes when the engine is running, you can clearly see the strain is all on the motor mounts.

When you use solids or poly engine mounts, the block essentially becomes a frame crossmember, and can take it.
The tranny, however, has that small aluminum ear, and just can't handle the strain. Put rubber there, and leave the engine mounts alone.
 
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