Hurt the 904 and 8.75 at the same time

[65TerrorCuda]

I'm guessing I hurt the overrunning clutch when I let off the throttle in manual 1st after spinning through a bumpy intersection. After that, it made a sound like the roller from an axle bearing being smacked against the transmission case randomly. Very inconsistent. Like the worst ping you've ever heard. Also feels like it's dragging in 3rd but not 1st or 2nd.

Any upgrades I should consider while she's down? Currently low gearset, 5.0 kickdown lever and a street strip VB, unknown make. I think it has an extra plate in the forward clutch but don't quote me on that.

 

[toolmanmike]

I'm guessing I hurt the overrunning clutch when I let off the throttle in manual 1st after spinning through a bumpy intersection. After that, it made a sound like the roller from an axle bearing being smacked against the transmission case randomly. Very inconsistent. Like the worst ping you've ever heard. Also feels like it's dragging in 3rd but not 1st or 2nd.

Any upgrades I should consider while she's down? Currently low gearset, 5.0 kickdown lever and a street strip VB, unknown make. I think it has an extra plate in the forward clutch but don't quote me on that.

Yep, sounds like you broke it. Low gear tire spinning can do that.

 

[remytherat]

Did the case break?

I assume you have no “first” anymore when in D?

 

[65TerrorCuda]

Did the case break?

I assume you have no “first” anymore when in D?

I don't think the case broke. No weird new leaks, just an occasional loud THWACK sound coming from the trans. Like you shot it with a sling shot. All gears work and seem normal except when in 3rd. Like it's laboring a bit. Neutral and park are normal.

I noticed the tailshaft bushing is worn but don't think it could be that.

Sure never made that sound before.

I should mention I haven't been into an automatic before, only manuals

 

[67Dart273]

There's no time like the present. Running it further is likely to damage parts in the transmission moreso.

 

[65TerrorCuda]

There's no time like the present. Running it further is likely to damage parts in the transmission moreso.

I'm with you brother. I was hoping just the axle was hurt but after full rebuild and upgrade on that guy there's still stuff that's off. The 3.91's bark 2nd when I'm not trying. Usually means there's a cop nearby.

Happy I didn't launch the driveshaft through the floor at least!

Can low fluid cause funny noises? After doing the axle, I thought it would be okay to drive around with however much fluid was left in the trans after letting it drain out the tailshaft since I'd removed the driveshaft. Turns out that's like 5 quarts. My bad. Adding fluid quieted it a bunch but it still makes goofy sounds. Don't wanna blow my foot off with a grenading 904.

Thanks guys for the responses! I'm half looking forward to taking this bad boy apart and half wondering how my 50 year old frame is going to feel. Probably going to need the tylenol for a week.

 

[crackedback]

If you can blow up an uncompromised front drum in a 904, you are spinning some BIG RPM. That is a 727/sprag problem.

If you think something is wrong, tear it down. Seen 904s run for a while with the sprag toasted. Is it smart... probably not. Fix it once. No need for fancy stuff there on a 904.

TF trans is simple to rebuild. Plenty of YT videos and guides. If you can build an engine, you can do a TF trans. Isn't any black magic in these things.

 

[65TerrorCuda]

If you can blow up an uncompromised front drum in a 904, you are spinning some BIG RPM. That is a 727/sprag problem.

If you think something is wrong, tear it down. Seen 904s run for a while with the sprag toasted. Is it smart... probably not. Fix it once. No need for fancy stuff there on a 904.

TF trans is simple to rebuild. Plenty of YT videos and guides. If you can build an engine, you can do a TF trans. Isn't any black magic in these things.

Much obliged! I appreciate the encouragement. Guess it's better to sweat a bit in the garage rather than say "hey what's that noise" every time I drive it. I may invest in some stouter jack stands meanwhile. Seem to remember getting the car high enough and not getting eaten alive by big ants was the challenge last time I had her out 25 years ago.

Dammit. Wish me luck guys.

 

[65TerrorCuda]

Thoughts on these?

 

[oldkimmer]

Look closely for hairline cracks. More than likely the tail shaft is bent. Kim

 

[65TerrorCuda]

Look closely for hairline cracks. More than likely the tail shaft is bent. Kim

Can't find any cracks yet. Lemme see if I can find anything off with that shaft.

Okay, so I'm getting a 2 thous hop in the setup pictured. It's zero right next to the bearing. Good call! Can that be straightened?

Edit: measured at end of shaft past splines, got 5 thous.

 

[oldkimmer]

Can't find any cracks yet. Lemme see if I can find anything off with that shaft.

Okay, so I'm getting a 2 thous hop in the setup pictured. It's zero right next to the bearing. Good call! Can that be straightened?

Edit: measured at end of shaft past splines, got 5 thous.

View attachment 1716458813

Your good, don’t even worry about.002 thou. Most trannys have more than that. .006 is the max I use. Kim

 

[Killer6]

I'm guessing I hurt the overrunning clutch when I let off the throttle in manual 1st after spinning through a bumpy intersection. After that, it made a sound like the roller from an axle bearing being smacked against the transmission case randomly. Very inconsistent. Like the worst ping you've ever heard. Also feels like it's dragging in 3rd but not 1st or 2nd.

Any upgrades I should consider while she's down? Currently low gearset, 5.0 kickdown lever and a street strip VB, unknown make. I think it has an extra plate in the forward clutch but don't quote me on that.

Wait, do You have a kit/valvebody that disables low-band apply in 1st? If not, there's no way the case sprag is the issue, the band would've had ahold of that drum. What IS possible is the stator sprag in the converter can often be damaged by that very move, I'd start by checking that.

 

[65TerrorCuda]

Your good, don’t even worry about.002 thou. Most trannys have more than that. .006 is the max I use. Kim

Excellent, thank you. I priced a billet shaft and hmmm ouch

Wait, do You have a kit/valvebody that disables low-band apply in 1st? If not, there's no way the case sprag is the issue, the band would've had ahold of that drum. What IS possible is the stator sprag in the converter can often be damaged by that very move, I'd start by checking that.

Good question. Is there a way to tell now that it's all apart? It was sometimes making a metal scraping sound like converter bolts hitting the dust shield, but I checked and that wasn't it.

 

[Killer6]

Excellent, thank you. I priced a billet shaft and hmmm ouch


Good question. Is there a way to tell now that it's all apart?

You can put the stator support splines in the converter to engage it, then rotate it back & forth, try to make a complete revolution & see if it jumps/binds/hangs up in the free-wheel direction. Anything other than smooth & free is not OK. You can then check the turbine the same way with the input shaft, it should be free & smooth both directions,.....often if the sprag fails hard enough, it can spit damaged rollers out, they will be floating & getting knocked around in between the housing/impeller, turbine, & stator blades.

 

[RustyRatRod]

Just an observation. The 5.0 kickdown lever is of no use without the Hemi width band......not available for the 904, but there some extra wide ones available. Without a wider band, that lever really does nothing and can actually slow the shift down. I've had it happen.

 

[65TerrorCuda]

You can put the stator support splines in the converter to engage it, then rotate it back & forth, try to make a complete revolution & see if it jumps/binds/hangs up in the free-wheel direction. Anything other than smooth & free is not OK. You can then check the turbine the same way with the input shaft, it should be free & smooth both directions,.....often if the sprag fails hard enough, it can spit damaged rollers out, they will be floating & getting knocked around in between the housing/impeller, turbine, & stator blades.

So I'm getting smooth rotation in both directions, no grinding or noises. I did both the input shaft and stator support, both are the same, no one-way action though! Is this the source of my noises?

Just an observation. The 5.0 kickdown lever is of no use without the Hemi width band......not available for the 904, but there some extra wide ones available. Without a wider band, that lever really does nothing and can actually slow the shift down. I've had it happen.

The wide one is rigid 2 1/16", narrow is not rigid 1 3/8", all frictions look close to new and are red. It wouldn't be hard to change the lever if helpful

 

[Killer6]

So I'm getting smooth rotation in both directions, no grinding or noises. I did both the input shaft and stator support, both are the same, no one-way action though! Is this the source of my noises?


The wide one is rigid 2 1/16", narrow is not rigid 1 3/8", all frictions look close to new and are red. It wouldn't be hard to change the lever if helpful

If the stator is turning both ways, try turning it & change directions back & forth, if it doesn't grab & lock one direction it's toast.
If it does lock, it should do so quickly & smoothly. It's not going to stop You from being able to turn the support splines, but You should feel it 'bump' & start turning the whole stator instead of just the hub freewheeling.

 

[65TerrorCuda]

No lock at all. It's totally smooth both directions. I can spin it either direction and it'll keep rotating like a top.

So it's had this loud thwack sound while idling for quite some time, you're telling me that was sprag rollers knocking around in the converter?

 

[Killer6]

No lock at all. It's totally smooth both directions. I can spin it either direction and it'll keep rotating like a top.

So it's had this loud thwack sound while idling for quite some time, you're telling me that was sprag rollers knocking around in the converter?

If it's been quite some time, the damage to the fins would've happened a while ago,....I DO know that I happened on an older SuperHoleshot B&M, & when I checked it out, I couldn't hear much of anything wrong until I really drained the fluid out as completely as I could, then I could shake it & it sounded like a big metal Maraca.

 

[RustyRatRod]

So I'm getting smooth rotation in both directions, no grinding or noises. I did both the input shaft and stator support, both are the same, no one-way action though! Is this the source of my noises?


The wide one is rigid 2 1/16", narrow is not rigid 1 3/8", all frictions look close to new and are red. It wouldn't be hard to change the lever if helpful

If you have the wider band, I'd leave the shift lever in place.

 

[65TerrorCuda]

If it's been quite some time, the damage to the fins would've happened a while ago,....I DO know that I happened on an older SuperHoleshot B&M, & when I checked it out, I couldn't hear much of anything wrong until I really drained the fluid out as completely as I could, then I could shake it & it sounded like a big metal Maraca.

It's got a drain plug, I could give her a rattle.

If you have the wider band, I'd leave the shift lever in place.

Now that I can do, much appreciated

 

[A body]

Excellent, thank you. I priced a billet shaft and hmmm ouch

If you priced the A&A input shaft it’s designed to mate with their output shaft so you’ll need both.

 

[65TerrorCuda]

I think you nailed it Killer! There's shiny dings all over the place inside the drain.

If you priced the A&A input shaft it’s designed to mate with their output shaft so you’ll need both.

I appreciate it! Looks stout alright

 

[Killer6]

View attachment 1716459192View attachment 1716459193

I think you nailed it Killer! There's shiny dings all over the place inside the drain.


I appreciate it! Looks stout alright

Well, I was hoping I was wrong, good new juicewheels ain't cheap. Whose converter is that? It's been 2 different colors, they may be able to fix it for less, curious if You can get a piece to come into view there....