Rear Tires Suddenly Lock Up Going 65

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The cracked brake shoe material seem to be the clue here.
Either fluid not returning to the master cyl or overadjusted brakes, as they get cracks in them when they get overheated.

Let's see.
My original post on this was heated brake lines causing a hydraulic lock, and overadjusted brakes would make it even more pronounced.

I'd bet you have a high and tight brake pedal, no?
 
They are majorly cracked and need replacement, both sides. Drums are ok.

The pedal does sit rather high.

Havn't been able to get much farther on it, my help to get the center section back in suddenly had to do something else and I'm waiting on a nice floor jack to help out instead.
 
T56MaxTorq said:
They are majorly cracked and need replacement, both sides. Drums are ok.

The pedal does sit rather high.

Havn't been able to get much farther on it, my help to get the center section back in suddenly had to do something else and I'm waiting on a nice floor jack to help out instead.
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So did you ever find out what happen?
 
Nope, no idea. Must be the transmission. Ive driven the car since and It drives normally. I'm going inspect and rebuild the trans along with a brake job.
 
T56MaxTorq said:
Nope, no idea. Must be the transmission. Ive driven the car since and It drives normally. I'm going inspect and rebuild the trans along with a brake job.
Click to expand...

I have been following this thread. You have a likely clue with the cracked brake shoes. The reason the crack is heat or poor quality brake shoes. When you removed the drums did you back off the adjusters?
 
My money is on the brakes, Hose etc... I replaced my brake shoes and did not realize there are two sizes of shoe on each wheel. Only about an inch difference, One primary and one secondary. if put in the wrong place will LOCK UP A WHEEL! Of course you had both rear wheels lock up, so either the wrong shoes in the wrong place on both rear wheels, or it's the hose! At any rate let us all know the outcome.

Boggled minds want to know!

John D. Beckerley
Austin, Tx.
 
The drums came off easily but not too easily. Didn't have to adjust anything. I havnt touched the brakes since. Been trying to reproduce the lockup at slower speed but nothing has happened. I'm on leave so it'll be a while til I get back and do the brakes. Then the tranny comes out. The saga continues haha yes it is mind boggling.

I meant to study the 904 plumbing and was gonna see if it's even possible for such a thing to happen, even after a few seconds from the last upshift into third. If the kickdown band for second stays applied in third along with the front clutch for third..what happens??? Haha
 
Check out a ATRA 904 catalog.If you going through it anyway,well worth the price.
 
For what it's worth my mistake in putting the shoes on wrong took over a year to reveal itself. Drove great over 800 miles, untill one day! Bam right front wheel locked. So I am just saying that if the shoes are installed incorrectly you may not notice by a mere quick look at them. The last brake job even if you did not do it can still be the cause! Just thinking inside the box on this. In my opinion you would of had something break "if" the tranny went into reverse, for only a second, you would of heard it! The senario you describe leads me to believe, either rear end gearing malfunction, or more likely the rear brakes. I still bet on brake issue!
 
Forgot to mention, the primary brake shoe (smaller one) goes in facing the front of the car. So having the secondary shoe on facing front on both wheels would cause that problem. Maybe even on one wheel since you have a suregrip!
 
The brake shoe theory is one to investigate. I didnt inspect for this last time the tires were off. I should have posted a pic of the tire marks on the road.. They look like an anti-lock brake lockup in some areas. Maybe this was just the tires "skipping" ..I dunno. I'll defiantly let you guys know what I find. Phil
 
I sold this demon to a friend. It had 323 gears when sold. Wound tight second gear would go over 100mph . The guy took it to a a shop and had some work done on the trans, fluid, filter ,adjust bands ,and removed reverse manual valve body and replaced it with the original. possibly other work.

He gave it to his son the next night. his son was dead within a hour.

Afterwards some time later the father bought a challenger off of me with a bad trans. he had a tail shaft housing which was cracked put on the Demons trans and it was installed in the challenger.

His son in law who I was working with at the time was using the challenger. While he was entering a four lane highway on a ramp . He pulled it down into second and wound her up . When he shifted to drive the rear wheels locked up and he spun several times.


It wasn't until this accured that we finally figured out what happened to his son in the Demon. The trans was tore down and the trans shop said the only thing they could find was the bands were not adjusted properly. The rebuilder at another shop believed that the bands should have been loosened up when the manual VB was removed and possibly causing it not to release when shifted. After this I decided Automatic transmissions should be left to the professionals with experience and proper tools to be pressure tested before driven.
 

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That car is a mess and it is sad that it cost a young man his life.
I leave trannys for the professionals too. Sounds like a match with the op's problems. I would like to see this figured out since it has now been nearly a month. If he don't quit driving his car this may be his future.
 
Oldmanmopar said:
I sold this demon to a friend. It had 323 gears when sold. Wound tight second gear would go over 100mph . The guy took it to a a shop and had some work done on the trans, fluid, filter ,adjust bands ,and removed reverse manual valve body and replaced it with the original. possibly other work.

He gave it to his son the next night. his son was dead within a hour.

Afterwards some time later the father bought a challenger off of me with a bad trans. he had a tail shaft housing which was cracked put on the Demons trans and it was installed in the challenger.

His son in law who I was working with at the time was using the challenger. While he was entering a four lane highway on a ramp . He pulled it down into second and wound her up . When he shifted to drive the rear wheels locked up and he spun several times.


It wasn't until this accured that we finally figured out what happened to his son in the Demon. The trans was tore down and the trans shop said the only thing they could find was the bands were not adjusted properly. The rebuilder at another shop believed that the bands should have been loosened up when the manual VB was removed and possibly causing it not to release when shifted. After this I decided Automatic transmissions should be left to the professionals with experience and proper tools to be pressure tested before driven.
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Oklacarcollecto said:
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That car is a mess and it is sad that it cost a young man his life.
I leave trannys for the professionals too. Sounds like a match with the op's problems. I would like to see this figured out since it has now been nearly a month. If he don't quit driving his car this may be his future.
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I too would like to see what he finds out....Not only if I get in the same problem but for others also....
 
I only mention the brake deal because it happened to me personally! So the deal is with the brake adjusters, after a while the shoes go all the way out and are so tight that they will lock the wheels. After seeing the last post and a tragic story with the Demon. If I were you I would tow it to the nearest tranny shop and at least have them check your work! It will only save you time and maybe your life!
 
These cars can kill you--I don't give a **** how good-safe you drive. In any car, when your on the road you are at more risk for death or injury then you are in your house or in the yard.

That car looked like it lost control and went sideways in to a tree, this is why roll bars aren't a bad idea for any car--how air bags came about instead....roll eyes. Well the air bags knock your hands off the wheel and stops the car from being used as a weapon, roll bars might help you keep on going after a good smack--Crazy Larry / Dirty Mary, lol..but the train still got them
 
Been a while - sorry guys. Have finally torn down the 904 in the Duster to inspect. Only thing discovered majorly wrong is that the front clutch drum is destroyed. The kickdown band wore through all the friction material and fkd it up good. That's it so far, pics to come soon.
 
T56MaxTorq said:
Been a while - sorry guys. Have finally torn down the 904 in the Duster to inspect. Only thing discovered majorly wrong is that the front clutch drum is destroyed. The kickdown band wore through all the friction material and fkd it up good. That's it so far, pics to come soon.
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That could cause it. It's possible the band hung up on the drum which would cause it to be in 2 gears at the same time. I've worked on torqueflites with severe 2nd to 3rd shift overlap and it'll really jerk ya. I could only imagine what it'd be like to totally lock up.
 
I have a stupid suggestion that could well be the answer. Is it possible the emergency brake cable either caught on something like the drive shaft or possibly something under the car? When the car was brought to a complete stop what ever was caught may have released or fallen. It would explain the over heated/cracked brake as well as the locked brakes. Just a thought.
 
Could the front clutch assembly be ruined by putting the car in reverse while going forward?
 
.............If the lining was torn off the front band, u found the problem, it hung up on the drumb, causing it to not release therefore it was in 2 gears at once.........kim........
 
If it happens again, shift the transmission into neutral. The engine will rev but at least the rear wheels will turn. If it doesn't, you have more problems than just an overapplied front band.
 
I don't think the e brake had a problem, it seemed okay while I was under the car taking the tranny out. The clutches and steels looked really good. While browsing for kits online I noticed a lot of rebuild kits out there only include gaskets, clutches, steels, and the rear band, if any band at all. It's worth changing all friction materials when doing a rebuild.

I have access to a non-destructive inspection lab, would it be worth to have the transmission case and other parts inspected for cracks? I was thinking the case, the input/output shaft, maybe the planetaries. It was a quite a violent lockup. Happened pretty quick, didn't think about neutral. Both hands on the wheel and foot on the brake.

Phil
 
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