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Steering shaft diameter?? (Help!!)

Rockett

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Can anyone help me out here?
I bought a new lower steering shaft bearing for my '68 Road Runner (4spd on the floor, power steering). The inside diameter of the bearing is 1", but my steering shaft is 3/4" dia. This is the way it is in my car, too (as pictured below), but I thought that the old bearing was just badly worn.
Now I'm wondering if I have the correct steering shaft in my car.
Can anyone with a similar B-body tell me what the diameter of their steering shaft is, at the lower bearing (under the hood, at the firewall)?
Does it make sense that the bearing dia. is 1/4" larger than the shaft dia.?
I was going to do this bearing replacement early tomorrow morning (Feb 02) but now I'm wondering if this makes any sense.
Thanks for any help or info!
Rick
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I just fixed this exact same issue with my friends GTX. I used an upper bearing and the rubber casing on the inside of that new bushing. It fit perfectly inside the back of the new bearing assembly. And centered that shaft and made it turn smooth with no wiggly feeling. I did this today.. But this shaft had already been converted to the Ujoint style end. So I popped that off and did everything from the bottom of the shaft.
 
I just fixed this exact same issue with my friends GTX. I used an upper bearing and the rubber casing on the inside of that new bushing. It fit perfectly inside the back of the new bearing assembly. And centered that shaft and made it turn smooth with no wiggly feeling. I did this today.. But this shaft had already been converted to the Ujoint style end. So I popped that off and did everything from the bottom of the shaft.
I don't understand.
This is the lower steering shaft bearing at the firewall under the hood. (You used an *upper* bearing?)
I was also going to do everything from the bottom of the shaft. I was going to remove my coupler from the end of the shaft (just rebuilt it a few weeks ago, so that seemed the easiest way to go), and simply slide the old bearing off the end of the shaft (two bolts up near the firewall) and then slide the new bearing onto the shaft & then put the coupler back on. But, of course the bearing is 1/4" larger dia. than the steering shaft.
The new [lower] bearing (pictured above) is like white nylon, with a metal ball-bearing insert (no "rubber casing" on the inside).
I guess I'm just not following your explanation here.
 
The bearing I had was off the bottom of my 66 shaft. Its the same size as the top bearing. But the lower one had a rubber casing and it was the exact same size as the hole on the back of the lower bearing. I should have made that clear.
 
The bearing I had was off the bottom of my 66 shaft. Its the same size as the top bearing. But the lower one had a rubber casing and it was the exact same size as the hole on the back of the lower bearing. I should have made that clear.
Well, my idea this morning is to maybe make some sort of "insert" (rubber?) for the center of this lower bearing. I'd need something 1" dia. with 3/4" inside dia. to snuggly hold onto the steering shaft as it turns inside that 1" inside dia. bearing (I guess).

FSM simply shows that bearing fitting around the steering shaft, without any kind of "insert". That's why I was wondering if my 3/4" dia. steering shaft is correct.

Anyone with a 68/69 Road Runner or GTX who can tell me the dia. of their steering shaft (under the hood before it goes thru the bearing at the firewall area)? And does the bearing fit nicely around the shaft? From the photo above, you can see that my steering shaft isn't even centered in the bearing.

Thanks, guys!
Rick
 
Hey I found the part I used. https://www.detroitmuscletechnologi...MIsr-DpN3L5QIVzJ-zCh37OQ4sEAQYAyABEgL35fD_BwE This thing slips right in the back of the big plastic piece and centers the tube. But you have to do it by taking the entire shaft out of the column. Up top you have 2 snap rings. One above the bearing and one below it. Once you remove those you should be able to slip the entire shaft out the bottom. This picture shows the lower column bearing from the side you insert into the column. All You need to do is put the rubber ring over the upper bearing with a little grease on the rubber. The slip them into the column bearing. just like you see it in the picture below.

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Hey I found the part I used. https://www.detroitmuscletechnologi...MIsr-DpN3L5QIVzJ-zCh37OQ4sEAQYAyABEgL35fD_BwE This thing slips right in the back of the big plastic piece and centers the tube. But you have to do it by taking the entire shaft out of the column. Up top you have 2 snap rings. One above the bearing and one below it. Once you remove those you should be able to slip the entire shaft out the bottom.
That thing looks like a very big diameter. I need something like that but smaller, to fit into the 1” hole of the bearing race... and that the 3/4” steering shaft can then fit thru. That link shows a rubber piece which looks like it’s over an inch in diameter.
BTW... I’m realizing that I’m going to have to pull the steering shaft or column out of the car in order to use a *press* to remove the coupler shoe pin! I have a “rim blow” steering wheel. Can’t figure out how to remove the center horn section on the steering wheel.
Anyone with any hints??
 
The upper bearing is smaller. It fits the lower shaft perfectly. I did have to sand down the paint on the shaft to get it to slide on. Thats how small in diameter it actually is. The picture might be a little deceiving.

I edited 3 pictures into one to show what I mean. forgive the crude photo shopping. But it all fits into the back side and as long as yo sand down the paint on the shaft the upper bearing slips right over it. The bearing and rubber effectively reduce the size of the one inch bearing to the 3/4 you need. If you remove the coupler pin from the bottom of the shaft this will be even easier. Thats how I did it. On that page it gives the dimensions of the bearing and rubber that I posted. Here are those dimensions. Mopar part# Isolator 2925491 and Bearing 2265656 Dimensions 1.190"OD .750"ID .250"Ht You cannot do this from the top down. You have to do it from the bottom.. Sorry to mislead you. In my cause the steering shaft was already setup with the swivel ujoint style coupler. I pulled it back off. You can get the same results by removing the OE style coupler. and the pin that goes through the shaft.

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2 questions for you.

1.Was your car at any point a manual steering gear car?
It looks like someone may have collapsed the shaft to fit in a power steering box. Which would make the shaft shorter but in turn shoving the fatter part of the shaft farther up in the tube past the large bearing.
2.Is your car floor shift,column shift or 4 speed? Or manual steering with 4 speed or floor shift auto/power steering or column shift power steering
There are 2 different length shafts. Manual steering and power steering. Power steering will have a shorter shaft.
 
Can I ask why the op doesn’t just get a bearing that fits. Pretty common I would think. Kim
They sell only one 2 bolt style and one 3 bolt style. Pretty sure the bearing sizes are both the same.
 
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Well, my idea this morning is to maybe make some sort of "insert" (rubber?) for the center of this lower bearing. I'd need something 1" dia. with 3/4" inside dia. to snuggly hold onto the steering shaft as it turns inside that 1" inside dia. bearing (I guess).

FSM simply shows that bearing fitting around the steering shaft, without any kind of "insert". That's why I was wondering if my 3/4" dia. steering shaft is correct.

Anyone with a 68/69 Road Runner or GTX who can tell me the dia. of their steering shaft (under the hood before it goes thru the bearing at the firewall area)? And does the bearing fit nicely around the shaft? From the photo above, you can see that my steering shaft isn't even centered in the bearing.

Thanks, guys!
Rick
The rubber Idea would work. But you have a load on that shaft I would expect a rubber bushing would not last long or it may squeak like hell at some point.
 

UGH .... that makes perfect sense. I had the entire column out on Saturday in order to press out the coupler shoe-pin, in order to get the bearing up onto the shaft. Unfortunately, I didn't think to try to pull the shaft to full length (...that's *her* job).
But, perhaps I do have a manual steering shaft that's been collapsed enough for the power box. Is this a common technique when adding a power box to a manual car?

As it is now, all put back together, the new bearing hardly does a thing, except that the shaft touches just the right side of the bearing a bit. Hardly seems like that lower support bearing is even needed, as the steering box itself seems to support the end of the shaft just fine.

Is there still enough "crash protection" with the shaft collapsed a bit like that? I know that I collapsed the shaft even further when I was working on the coupler & removing the column (extended on reinstall), so there *is* more "collapse available."
 
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Well I know people havetried different methods to recreate the plastic shear pins. I thought maybe to use nylon nuts and bolts and just drill the hole all the way through. Surely the nylon would sheer off with little force. Which would be similar to the way it worked from the factory.

Also. To mention look at the picture of the shaft I posted above. Now look at the distance from the coupler to the start of the tapered part. Now look at the shop manual picture. The shop manual shows a power steering column that distance is shorter. And the longer distance shaft I posted is for a manual steering car.
 
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UGH .... that makes perfect sense. I had the entire column out on Saturday in order to press out the coupler shoe-pin, in order to get the bearing up onto the shaft. Unfortunately, I didn't think to try to pull the shaft to full length (...that's *her* job).
But, perhaps I do have a manual steering shaft that's been collapsed enough for the power box. Is this a common technique when adding a power box to a manual car?

As it is now, all put back together, the new bearing hardly does a thing, except that the shaft touches just the right side of the bearing a bit. Hardly seems like that lower support bearing is even needed, as the steering box itself seems to support the end of the shaft just fine.

Is there still enough "crash protection" with the shaft collapsed a bit like that? I know that I collapsed the shaft even further when I was working on the coupler & removing the column (extended on reinstall), so there *is* more "collapse available."
I have 1 buddy that does a temporary fix with a piece of hose the right size. He slices it then slips it over the shaft and up into the column a few inches and then secures it with a hose clamp. Kim
 
I have 1 buddy that does a temporary fix with a piece of hose the right size. He slices it then slips it over the shaft and up into the column a few inches and then secures it with a hose clamp. Kim
Kim, your buddy does that to increase the diameter of the shaft to fit inside the bearing??
 
Well I know people havetried different methods to recreate the plastic shear pins. I thought maybe to use nylon nuts and bolts and just drill the hole all the way through. Surely the nylon would sheer off with little force. Which would be similar to the way it worked from the factory.
What purpose do the plastic pins serve? I thought those just made installation easier at the factory. Since, once the shaft/column is installed, it’s not going to extend or retract unless something really hits it hard (collision), moving the steering box. I know that the plastic pins from the factory will shear in a collision, but if they weren’t there in the first place, what’s the difference? (Other than perhaps installation on the assembly line would require adjusting the length).
 
They are so that in the event of a crash the shaft doesn't become a spear and go through the drivers chest. The collapsing column is a safety feature I think brought to the columns in 1968 but don't quote me on that. I do know the 66 has a solid shaft and possibly 67.
 
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