TT drive shaft front bushing question

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration
Model T Ford Forum: Forum 2008: TT drive shaft front bushing question
Top of pagePrevious messageNext messageBottom of page Link to this message  By Michael W. Herndon on Saturday, January 24, 2009 - 06:46 pm:

I need some help with a part:

The front bushing that is pressed into the torque tube housing to support the drive shaft is worn. The rivet pin that holds the U joint to the drive shaft was broken and I know I need to replace the bushing. There is a new part, a roller bearing, that replaces this bushing... seems good to me, what does everyone think?

Attached are pictures of the drive shaft, bushing, and U joint. These came out of the Rocky Mountain 6 speed transmission and I want to use it in the TT.

I think I might need a new U joint (this one was completely rusted, but I broke it free and now it moves easily but the surfaces are pretty tight. Little movement. But some.

The bushing is loose, not a press fit at all, and it rocks on the drive shaft as if it is worn irregular, and the inside is a bit rough and worn.

So, what is the answer from the group that knows? !! ??

Thanks..

Michael


Top of pagePrevious messageNext messageBottom of page Link to this message  By John F. Regan on Saturday, January 24, 2009 - 07:14 pm:

In a normal T driveshaft there is very little load on the upper end of the driveshaft. The bushing in question normally only carries a portion of the weight of the upper end of the driveshaft. Greased with just about any amount of lube - the bushing will last a very long time and bushings run quiet compared to bearings. A simple twist of the grease cup now and then and you are good to go. In any event it is ALWAYS a bad idea to run a hard bearing against a soft shaft and that is what that needle bearing piece of bad engineering is all about. Replacement bushings are placed at points to allow you to replace a worn bushing rather than a worn shaft. With a hard steel needle bearing riding against the "soft" upper end of the driveshaft - it is the driveshaft that will eventually need to be replaced - not the bushing/bearing - that is bad engineering. There are many places where a hard bearing that might never wear out is more of a problem than it is a fix. I have a ton of miles on the bushing in my T and it shows no signs of wear yet.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Bob Jablonski on Saturday, January 24, 2009 - 08:35 pm:

Michael:

I had good luck with bushing replacement. Bushing will compress a bit when driven into housing, making the inner diameter smaller.

Drove the bushing with a socket & hammer, driveshaft fit snug without noticeable play. Be sure to drill for grease hole.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Andy Loso on Saturday, January 24, 2009 - 10:15 pm:

Micheal,

I am trying to find out why there is a flange on that bushing? A TT DS bushing, doesn't need a flange as the ring and worm just mesh there is no reason to cut the thrust as in a regular T rearend. We just had the machine shop make a new one from bronze, when they shortened our DS for the warford.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Adam Doleshal on Sunday, January 25, 2009 - 02:03 pm:

I've had to make these bushings, and we don't put any flange on them either... Because everything is held in proper alignment by roller bearings and thrust bearings at the lower part of the rear end, a flange is not needed. (If anyone thinks otherwise, please chime in... maybe I am missing something.) My guess is the flange was there to prevent them from being pressed in too far on the production line.

Now, In a regular T car driveshaft, you absolutely do need the flange to maintain proper gear mesh.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Andy Loso on Sunday, January 25, 2009 - 03:01 pm:

Our original TT babbitt DS bearing stamped with "Ford" had no flange. I don't think there ever was a flange, maybe someone put a car one in thinking it would be good enough because they didn't have access to a lathe or machine shop?


Top of pagePrevious messageNext messageBottom of page Link to this message  By Adam Doleshal on Sunday, January 25, 2009 - 04:47 pm:

TT bushings are bigger than car ones. They are not interchangeable.


Top of pagePrevious messageNext messageBottom of page Link to this message  By miltont on Sunday, January 25, 2009 - 05:11 pm:

The U joint rides on the face of the flange after you pin it to the shaft. Otherwise the drive shaft will slip back into the differential and make for some interesting repair.

I'm currently restoring a 26 Tudor that my dad bought over 50 years ago and during the Richmond celebration numerous people I spoke with recommended that I tear into the rear end. That was a can of worms as it turned out. The U joint pin was gone and this apparently permitted the drive shaft to float back and forth. It had been up against the three differential housing bolts for some time, the heads where half gone. Don't know how much farther it would have gone before the the bolts would have been gone completely. Naturally there was other damage, like no bearings, just 6 thrust washers.

The Forum is a good place to get feed back, even though some of the questions and answers isn't always what we want to hear.


Top of pagePrevious messageNext messageBottom of page Link to this message  By Adam Doleshal on Monday, January 26, 2009 - 01:21 pm:

"The Forum is a good place to get feed back, even though some of the questions and answers isn't always what we want to hear."

miltont, We are talking about a TT truck drivetrain. It is entirely different than a car drivetrain. The TT drivetrain has a worm gear attached to the driveshaft that is supported by both roller bearings and thrust bearings on both the front and back sides of the rear axle housing. This controls both forward and rearward thrust making any "face" on an upper driveshaft bushing redundant. In a TT truck, as a matter of fact, not only do you not need a face on the upper bushing, but you don't even really need to rivet the u-joint to the driveshaft either (although I always do rivet the u-joint myself just as a matter of proper practice, but I do know people who didn't and it never caused any problems).

Now, on the other hand, when you are talking about Model T cars (which you were) with the "regular" axle; Yes, the proper facing of the bushing is a very important aspect of rebuilding the drivetrain as it does control gear mesh...


Top of pagePrevious messageNext messageBottom of page Link to this message  By Michael W. Herndon on Monday, January 26, 2009 - 04:04 pm:

Thanks for all of the input. I have learned much.. I think..

My TT came with a Rocky Mountain transmission (called a 6 speed although it is has 3 speeds inside.). The drive shaft that fits this is the one I am talking about. Naturally, it is shorter than the regular one. I have not removed the normal long drive shaft yet and it will be interesting to see what is inside for the bearing in question.

I will be replacing the U joint because the one that came with it was rusted.. It cleaned up well, but as long as it is apart I might as well put in a new one.

The rivet that held the U joint to the shaft was separated in the middle. Reading the pamphlet put out by this group on this states that if the rivet is broken, then this means that there was too much movement in the U joint, the bearing, or the drive shaft and that this needs to be corrected or the rivet will break again. Now I hear that this rivet is not important.. and the bearings that are sold by the vendors are the ones with the face on the bushing, and they are not for the TT?

Hmm.. Well, what is suggested? The drive shaft is held well by the U joint. A bushing is needed, I would imagine, but perhaps one made at a machine shop rather than through the vendors. The Drive shaft is also held well into the RM transmission (proximal to the engine) and the back of the transmission fits to the worm gear front, the spindle part being part of the transmission (different than what I see of a regular T spindle).

So, I should not worry about the broken rivet? (naturally I will replace it..).

Thanks guys..

Michael


Add a Message


This is a public posting area. Enter your username and password if you have an account. Otherwise, enter your full name as your username and leave the password blank. Your e-mail address is optional.
Username:  
Password:
E-mail:

Topics Last Day Last Week Tree View    Getting Started Formatting Troubleshooting Program Credits    New Messages Keyword Search Contact Moderators Edit Profile Administration