Well, I just got my truck fixed today. It was leaking oil from the front portion of the drive shaft (I forgot what it was called). Anyway, I had 4" aluminum before and now they replaced it with a humongus 5" aluminum. I thought that was cool. Anyone have this new updated version?

 

The transmission extension housing seal was leaking. There was a problem with driveshaft vibration causing the seal and bushing to back out of the extension housing and cause a leak. Sometimes the leak was really bad. There are a few stories I've heard about huge clouds of smoke because the leak is right above the exhaust pipe.

Part of the fix is to install a 5" diameter driveshaft.

Out of curiousity: Had you been driving pretty fast before this leak?

 

well, yes. as a matter of fact, i drive about 100 miles a day and about half those miles above 80 mph. Sometimes i drive 100+ when there are no other cars around on the freeway. this is my 3rd drive shaft and I am 3k miles away from 36k. Well, I guess i'm gonna slow down.

 

Where did you get the 5" driveshaft, I have the same problem.....

Thank you,
Ricardo

 

cato,

A 5" driveshaft is not cheap. His, I believe, was replaced under warranty. If you needed to buy one:

1L3Z-4602-BB 5.4L 9.75 Differential 139" WB $322.13

1L3Z-4602-CA 5.4L/4.6L 10.25 Differntial 139" WB $322.13

F85Z-4602-BB 4.6L/4.2L 8.8" Differntial 139" WB $319.57

F3LY-7A039-A Trans Extension Housing $102.37

F6AZ-7086-A Ext Housing Gasket $10.20

You can see that this is not a cheap fix, if you're paying instead of Ford. When you say that you have the same problem: do you mean that yours is leaking as well??? The 5" driveshaft and the revised extension housing work together. You can't really replace just one of the two if you want to fix the problem. You can replace all these parts yourself, but it's still going to be around $350.00, even if you don't need to pay dealer list for the parts. You may call some driveline shops and ask if they can build one as well.

Did you try indexing the driveshaft yet??? Make sure that the indexing marks line up from the tailshaft back to the companion flange. If there are no marks: Just unbold the driveshaft from the companion flange and rotate it 1/4 turn. Then bolt it back on and go for a drive. If it still vibrates, do it another 1/4 turn. If you go all the way around, and it still shakes, try just 1/8 turns until it's as smooth as possible.

A driveshaft is naturally unbalanced. What you are trying to do is cancel out the vibrations of the transmission tailshaft, driveshaft and companion flange.

I guess you've already replaced the extension housing, huh


Read this as well: Drivetrain Vibration: Facts, Myths, and Possible Solutions.

 

AjRagno, thank you for all your info. I have been having a vibration in my driveshaft for a long time causing the tailshaft housing to leak. Nobody so far has been able to solve my problem. I have done all kind of things you can imagine. I changed the u-joints, I rebalanced the driveshaft, changed the tailshaft housing extension (by the way, How did you know that I changed it???), tranny mount, etc......I'm desperate, I would like to try a new driveshaft to see if that solved the problem, but I dont know, any other suggestions????

Thank you,
Ricardo...

 

When they (Ford Dealership) fixed my vibration problem, Ford had a TSB for it. It comes as two folds. One, replace with 5 inch shaft. Two, reprogram PCM so that top speed is reduced by 8MPH. Only the first was done since I work at the dealership and they know my truck hits 100+ MPH at least once a day. So, technically it seems they are minimizing vibration by reducing velocity and adding more weight. My .02

 

cato,

I'd seen your post at the other site. That's how I knew you'd changed the extension housing.

I suppose if it is leaking, you may need the whole fix. I think what you really need to do though is slow down. Anything over 85mph can cause this leak.

You may also want to try indexing the driveshaft. This only costs you in time, rather than money and it may help.

 

Thank you for the responses!! I read the web page regarding vibrations, and it is very good. I guess I'm going to try indexing the driveshaft, if not, I'll try the 5" one. Thank you guys, I'll let you know!!

Ricardo.