Okay, I've searched and read through a lot of stuff over the past few days and now I'm going to appeal to you guys for help.

This is my only vehicle and I have to get to work, and I cannot afford to put it in the shop.... so I need fast help!

Truck is a 2000 F-150 4.6l Triton V8. 2wd
I'm not sure what model transmission, but I'm sure you guys know. (it has OD)

Again, I need really fast help here, guys/gals so please be patient with me and try to follow...............

I recently replaced my U-joints which were shot.
The extension housing seal had come loose and started leaking transmission fluid, so while I had the drive shaft out, I replaced that.

Now, I have relpaced the extension housing rear seal (tailshaft seal..whatever you wanna call it) twice in the last week!

The only thing I can conclude is that there is some wobble that is causing it to work loose.
From my reading, the causes of this wobble can be from:
-bent driveshaft
-worn extension/output shaft bushing

I don't know how to check the driveshaft myself, so for now I'm going to eliminate that issue. (but we'll pick up on that later)

I'm going to operate on the premise that if I replace the extension housing/output shaft bushing, and then replace the seal, all will be well.
(for now)
I don't know how to tell if the bushing is worn to the point where it would be causing my seal to pop out.
The output shaft does have some movement in all directions, but I'm not sure how much is too much.

Right now the driveshaft is installed and the yoke (which is installed onto the output shaft) also has movement in all directions.

For now, that is my question....
How much play in the extension housing/output shaft is too much?
and
Could this alone be causing my seal to come out? (bad bushing)

Thanks!

 

Welcome to FTE sixgunner! I'm no expert but, I would think that you are using an inferior seal. You could have a drive shaft that is out of balance too. Do you get any vibrations when driving the truck? How bad were the u-joints before they were replaced?

 

Thanks for the welcome, this is a great site and I wish I had found it earlier.

The driveshaft very well could be out of balance, and I will consider that, but I think first I'd like to find an answer to my other questions re: the bushing/shaft play because if I can get it going from there, maybe it'll buy me some itme....I dunno'.
The U joints were completely shot....right before I replaced them, there was some vibration and like i said it was bad enough to pop the extension housing seal out.

My immediate thinking on this is that I could replace the bushing and seal and it might stay put long enough for me to get the drive shaft looked at.

Maybe that's backwards thinking, but I'm really at my wits end here and I'm desparate because this is my only ride to work and I can't afford to take it to the mechanic...

I'm sure I've done a lot of damage by driving it thus far, but I really didn't have any choice because I got stranded so I just kept dumping tranny fluid in it until I got home.
(It never did run completely dry even with the seal hanging loose)

EDIT TO ADD:
When I replaced the output shaft/extension housing seal a couple of days ago, I didn't notice any undue vibration at all while it was still good.
It just started smoking when the seal came out and dumped tranny fluid everywhere.


Any help at all is apprieciated.
Thanks

 

Okay....

I did some more reading in another thread and have more similar questions.
I know some of this is repetitive, but please bear with me because I copy/pasted from the other thread................


Question:
Is the driveshaft yoke that slides over the output shaft supported by a bushing down inside the extension housing... or just the seal?

I know there is an output shaft bushing listed and I'm thinking that if it's worn, that is what is causing the play, and therefore causing the seal to be knocked out repeatedly.

With everything installed properly as it is now, I can grab the driveshaft and wiggle it around a lot.....it's very loose w/ a lot of play.....the only thing stopping the travel of the play is the seal!
This leads me to believe that the extension housing bushing needs to be replaced to fix this problem.
Thoughts?
and
where can I get this bushing quickly for the cheapest?
any links or part numbers will help


I really need to do this in the next day or two because this is my only means of transportation to work!

My other line of thinking is that the driveshaft is out of balance which it very well could be....

I'll deal with that later, because I'm thinking that if the problem (play) is caused by a worn bushing, then I can get by with only replacing that until the weekend when I can get time to find a driveshaft or have mine repaired.(if it needs it)

Please HALP MEH!!!!!

 

OK. Since you are smart enuf and have the ability to change your own u-joints.I am pretty sure you have the ability to determine if your yoke and or tailshaft has to much play and is worn out.
When you had the D/S out for repair and seal out for R&R did you look at the splines on the output shaft of the xsmn?Not really a common part to wear out befora a yoke.So take a look.
Yes there is some type of bushing in the tailshaft(should be,all that I have seen did).Whether it is brass or machined into the tailshaft cone,I have no Idea since my books are at work.If it is brass any xsmn supply house will have it.Dont even bother with the box stores to find it.If its machined guess what!You wont be able to see it without taking the cone off.No big deal,just unbolt it and it comes off.At the same time you will be able to inspect the output shaft real easily.
You already have 1/2 the prob fixed.YA, you could have done it all at once but what would you have learned doing it right the first time
The d/s is NOT supported by the seal!Is there a groove worn arond the yoke were the seal would be making contact to form the seal? Or buildup that can be cleaned with emory cloth? Either one would make it leak.
If your driveshaft is bent enuf to cause all this you should be able to look at it and see a problem and you would have a hell of a vibration!

 

Thanks for your help.
I answered your questions above (in blue) because it was faster for me to do it that way.

I'm still wondering about a couple of other things and maybe you can help with those as well....

1) What model of transmission do I have?
From my quick research, I think it's a 4R70W, but I'm not 100% positive and I think there might be two variations of those,even.
(I think I read an AOD and an AODE)
The truck is: 2000 F-150 extended cab, 4.6L Triton V8, XLT, 2wd, it has an overdrive "off" control on the shifter, and takes Mercon V fluid.
I'm assuming it's the 4R70W rather than the 4R100, but again I'm not positive.

2)Can the extension housing be pulled off without dropping the tranny or doing anything else?
If I need to replace the bushing or the housing, I'm hoping that I can just reach up and unbolt it rather than having to screw around with pulling the whole thing, etc.
I know it'll probably be a real PITA to reach the Extension housing's mounting bolts. *sigh* If I can do it at all.


Again, I have a feeling that if the bushing is too worn or spun, that the housing my be worn and need to be replaced altogether.
What leads me to believe this is that from what I've seen so far, the bushing is very very thin and doesn't have a lot of 'meat' to it.
*I have never physically seen the bushing in my truck*
For all I know it may no longer have one!

So for my driveshaft to have that much play, the housing would almost have to be worn as well.....but I'm just guessing and preparing for the worst.

Thank you very much.
6

 

In the event I do have to change the extension housing, I wonder which is the right one?

This:
U76770C Extension Housing, AODE/4R70W 2WD (10 1/2 Long) Large Seal (With Speed-O Hole) 1993-03

Or this:
U76770D Extension Housing, AODE/4R70W 2WD (11 1/2) Large Seal 1993-03

I got this info from this page:
https://www.wittrans.com/showfilter....23&Section=174

 

The only differance is lenght.Dont you have a tape measure? or ruler?

 

Well of course, but I'm not laying under the truck right now and I'm trying to find all of this out before I start pulling stuff....at least as much as I can while I'm sitting here this evening.
Oh...and apparently one has the "speed-o hole" and the other doesn't. I'm not sure how important that is, but I'm guessing it probably matters.

 

Okay...I'm searching but cannot find the bushing (I mean to buy)
Any help with that?

Sorry buy my internetz isn't cooperating very well

 

You can buy manuals for any type of xsmn.They are the size of a magazine and only cover that xsmn that you buy it for.I have bought them at napa and xsmn supply stores for about $10.It will hope you out alot to see what you have and need
If you have the 10 1/2 shaft it will have the speedo mount hole,11 1/2 wont

 

Ford does not service the bushing separately. You need a press and the proper sized adapter to press the bushing into the extension housing. If the driveshaft yoke moves around by hand a measurable amount when it's inserted into the splines on the tailshaft,then the bushing is gone. Here's the problem-if you ran it until the bushing is that bad, it's very likely that the extension housing is ruined as well. You can get the bushing for the housing,but it won't do you any good if the housing is ruined. A new housing with bushing and new seal is approx $150 from Ford(unless they've had a huge price increase recently). Either that,or a used housing that's known to be good would be the proper fix,along with a new drivehaft yoke. If you re-use a yoke that's been ran in that housing with a bad bushing,then the new housing will have a very short life,and you'll be doing this all over again soon.
BTW-your trans is a 4R70W,and uses the short housing. The only vehicles to use that longer extension housing were the Police Crown Vics and Town Cars.
JL

 

Thanks for the info!
Yes, I've decided to go ahead and just replace the housing too since I was able to find one.
As far as the yoke is concerned, when I tear it down again, I'll spec it out and if it's bad I will replace it too.....but I might have to use the old one until the new one arrives. Not ideal, but it shouldn't take too long I hope.

 

It won't take but 10-15 miles to ruin the bushing if the existing yoke is bad or damaged in any way.
JL

 

Update....

Well the yoke was fine when I replaced the U-joints.
It was also fine when the seal fell out a thirtime.
Unfortunately the last time it fell out, it did damage the yoke.....I broke down out of town, re-secured it and drowned the tranny with as much fluid as she'd hold and tried to wing it back to civilization which was a good 45minutes.


Anyway, my g/f's dad knows a good mechanic and I was able to finally get it to the shop...

They replaced:
Extension housing
Bushing
Seal
Yoke
balanced the drive shaft
...for a grand total of $248.00

I figured that I must have done some additional damage to the tranny by driving it back this way, but the mechanic said my tranny actually looked fine and I probably had nothing to worry about.
Maybe flooding it with tranny fluid offered a little bit of protection for the drive back...dunno'

I was prepared to do the work myself (and it was all I could afford to do) but I was not prepared for what a difficult task it would have been to actually remove the extension housing, particularly while laying on the ground under the truck.
I did recognize that the yoke was (this time) totally smoked!

I got to watch the guy work, and it was a real mess under there, especially filled with too much fluid.

Anyway, she's running great now and even though I ended up taking it to the shop, I want to thank you guys for all of your help with this.
What a great board!