Output shaft bent on a 904

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nephlyte

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I had violent shaking in my car. I suspected it was the driveshaft, but I replaced the driveshaft and it returned. Sure enough, the output shaft is bent.

I have looked around for a new one, but I can only find one from a Jeep 1960 and up:

http://www.ebay.com/itm/CHRYSLER-A9...Parts_Accessories&hash=item27cb2b74a5&vxp=mtr

Does anyone know if this is the same part? Anyone know where i might be able to find a part like this? That, or a cheap new 904 for my 66 valiant?

Any help on the subject is appreciated.
 
You do realize that you have to completely disassemble the trans. to replace the output shaft cause it goes in from the front, right?

What makes you think the output shaft is bent? If the output shaft were bent I can't see how it woulndn't break the extension housing cause when you slide the driveshaft yoke in it's a tight fit into the bushing. Is the bushing on the extension housing all beat to crap? How about the bearing on the output shaft.

When you said you replaced the driveshaft and it (being the vibration) returned do you mean it was gone for a while then returned or you actually saying it never really left, that it was still there after you replaced the driveshaft??
 
I do realize that the output shaft requires a full dis-assembly. Luckily I have a good mechanic who is better at such things than me. Typically i do all my own work, but when it comes to the insides of a transmission, i leave it to a professional.

Anyway, we know that its bent because he put a dial indicator on the end and rotated it. In real terms, its a minor deviation, but for a rotating part, that small bent on the end of the output shaft makes for some serious driving problems.

As far as the vibration (more like violent shaking), a few months after getting a new driveshaft (as my old one fell off the car and was stolen), the vibrations began. They start at 45 mph, and dissapear at 65 mph. Me and the mechanic assumed it was the driveshaft. So we replaced it and the vibration stopped for a short while (about 4 days), then returned with renewed vigor, starting at around 40 and going up to 75.

The bushing, it is totally beat to crap. I don't know about the bearing, i didn't ask him, but I will now. I assume if there is a bend in an important shaft like that, that bearing is going to be going out as well.

I'm thinking that I will not be able to find the right part and I will just have to get myself a new 904 :banghead:

Just to ramble now, this especially pisses me off because when the vibration returned on the new driveshaft, I also had my steering gearbox fail. This has all happened a month after i fully replaced all my brakes with new equipment and only a few months after i replaced the entire suspension with new parts. And it ran so great for the first 4 years i owned it. Hopefully I will get this sorted out and have a fully functioning car again soon.

You do realize that you have to completely disassemble the trans. to replace the output shaft cause it goes in from the front, right?

What makes you think the output shaft is bent? If the output shaft were bent I can't see how it woulndn't break the extension housing cause when you slide the driveshaft yoke in it's a tight fit into the bushing. Is the bushing on the extension housing all beat to crap? How about the bearing on the output shaft.

When you said you replaced the driveshaft and it (being the vibration) returned do you mean it was gone for a while then returned or you actually saying it never really left, that it was still there after you replaced the driveshaft??
 
Actually a worn output shaft bearing can cause the shaft to wobble as there is nothing else that really holds the shaft stable. The output shaft passes through the governor support about mid way which holds it in place somewhat but I'd suspect the ouput shaft bearing way before the ouput shaft. After all, hows a hardened shaft going to just bend?? In my 30+ yrs. of rebuilding transmissions (mostly Mopars but some GM's too) I have never saw a bent output shaft from a trans. unless the car was wrecked real hard. Not saying it can't happen but I don't see how it can unless something hits it real hard. Another thing, why did the vibration go away for a few days when you replaced the driveshaft? A bent shaft doesn't stop being bent for 4 days then go back to being bent again. I'd look the new driveshaft over as well to make sure it didn't toss a balance weight.

If you do need a new output shaft didn't you see the link Tony provided from Wittrans that shows output shafts dirt cheap? It's in post # 3. Here it is again

http://api.viglink.com/api/click?fo...LinkCode=678&jsonp=vglnk_jsonp_13550247727044
 
i know this is an old thread, but was the vibration issue really the tail shaft? Ive had the same kind of vibration for 17 years and LITERALLY the only thing that has not been changed is the output shaft itself. I just had a 904 rebuilt for me last year and the only thing that was reused was the output shaft. Even the case and tailshaft housing were replaced.
 
Well for starters you can't check the tail-shaft in the vehicle the way it was with a dial indicator, that has to be removed put between to dead centers and checked over at different locations of the shaft and then if it does have a issue it needs be rechecked in a v blocks on the bearing surfaces and then gone to the same areas it showed up in the dead centers.
So id bet he never had a good shaft or a non competent shop or the bushing was just worn out.

It is very possible to have a new shaft and have a vibe especially if it was bought thru shipping, and or using old stuff laying around isn't the way to say you checked it, shafts laying around could easily be knocked out of balance by being dropped or whatever else happened to them.
.

If you have a vibe for 17yrs you should have leaks also.
 
Well, alls i know is that i just found a freshly rebuilt transmission, swapped it out and the car has been running great ever since. I didn't notice before, but the transmission shifted poorly as well.

Lesson learned: It doesn't hurt to dump a little extra cash for the right fix.
 
I still think you got hasty, and missed a chance to learn something. These transmissions are easy to rebuild and deal with. It ain't voodoo, you flush money down the crapper every time you take it to some one.

Glad it worked out. Good luck.
 
Glad it's doing well for you now, '66 Valiant 200's are special. My Mom drove hers for decades and I clearly remember my baby sister being brought home from the hospital in it.

Ours was a beige V200, 225 auto, no radio or other options that I remember. What options does yours have? Looks like it has bumper guards and full wheel covers....
 
I don't know what options this thing came with. It has a power steering, radio, heater and 4 doors. When i got it, it had the original radio, which was neat, but I figured someone who is building up an original car could use it more, so I sold it and put in a real stereo.

Other than that, no power brakes, no AC, no other bells or whistles.
 
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