Omni Shift Linkage Rod Bushing

How to make the shifter rod rubber bushings that are no longer available from Dodge

Copyright 2011 by Morris Rosenthal All Rights Reserved

The Omni Project

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I've owned my Omni since it was new, 1986, and I remember having these shift rods (not the tube) fail before. It seems to me they failed on the end with the plastic or nylon snap fitting, not the end with the rubber or plastic bushing that fits over a ball. I say rubber or plastic because the mangled mess that was left of the first one (and the one I later blew apart because I wanted a template) had the look and feel of plastic. I just can't imagine plastic having enough give to fit over the ball, but let's start at the beginning. I was driving to an electronics auction yesterday morning when the shift linkage fell apart passing through neutral. Pulled over and put the mangled bushing back in again, it failed on the second/third shift when I restarted. Tried again with tie-wraps to hold it all in place. Made it to third gear and failed trying for fourth. So I gave up on the remains of the bushing and slit open a piece of fuel line I had in the trunk, using electric tape to hold it together when it slipped over the ball. Then I hopped on the nearest highway and made it home, though I largely stuck with third gear and burning the clutch once I got off the highway. The picture to the right is how the kludge looked when I got home. Note the top of the old bushing sitting on a sheet metal ledge next to it. Roadside fix to shifter bushing
Split fuel line as temporary bushing The picture to the left is just to show how simple a working roadside repair can be. I'm not sure how long it would have lasted, and the white nylon rod end isn't supposed to be sitting all the way down on the metal. So when I got home, I called all the Dodge dealers but nobody can get these parts anymore. I tried Internet search, but nobody had a source for the rods, other than junk yards, and I'm not enthusiastic about buying 25 year old junk yard parts that fail from age. I should mention that I replaced a couple shifter rods that failed when the car was fairly new, maybe just a few years old, and never had another problem with them until now. If they had failed regularly on me, I would have stocked up, like I did with the Hall Effect magnetic pick-up for the distributor. So I tried a few auto part stores looking for any bushing that I might modify without any luck, and ended up at the local hardware store where I bought a rubber stopper.
The picture to the right shows the nylon end which is bolted into the shifter tube, but that stuff is all so rusty that I hate to touch it. I don't know why shifter tubes rust so badly, must be made of the wrong steel or something. You can see the nut that holds that nylon end on, but they aren't available and it hadn't failed, it just needed a new bushing. All of the Internet fixes I've seen for this problem suggest converting to a Heim joint, a patented rod in ball joint type device that they sell at most hardware stores. But you really need good access to do the job, you need to cut off the ball and replace it with a rod or a bolt for the Heim joint to secure, and you need to find a Heim joint that will screw into that shifter tube (or re-tap it), since there's not a lot of room to play with. The rusty piece welded to the rusty shifter tube right behind the nylon end is an integral part of the shifting linkage, not something that can be ignored. I've added a few videos to the end so you can see the shifter rods in action, and I can see where I could install a clip or retainer without restricting motion. Close up of ball on shifter linkage and nylon end on shifter tube
Exploded view of Dodge Omni shifter rod bushing I wanted to get a better template for a new bushing than the mangled one from the lower ball, so I tried prying off the upper shifter arm, the one that attaches to the transaxle and is much easier to reach, just below the master cylinder. Not surprisingly, it blew apart, but it gave me a good look at the inside. You can't read the tape properly because of the camera angle, but the bottom lip of the bushing is actually lined up with the 2" mark, so the total height of the bushing is between 11/16" and 3/4". I went with 3/4" for my replacements and they were a little tall, so the factory bushing is probably 11/16". The ball diameter is 1/2" and the opening at the bottom of the bushing is 3/8". The lip on the top of the bushing (you can see the fragments that broke off piled up there) was about twice as think as the bottom lip, so let's call it 1/8" for the top and 1/16" for the bottom.
I'm going to use a couple pictures from the first bushing I made even though I ended up doing two more. The reason is I tried constructing the first bushing based on the mangled piece, and in test shifts, it started working it way off after ten or so times through the shift pattern. I had used a 1/2" drill, rather than 3/8", and I hadn't known there was a lip on the bottom. I might never have found out except I dropped the mangled bushing at some point and it fell down behind the battery and dropped alongside the overflow reservoir, which I didn't feel like taking out. To the right you can see the mangled bushing next to my first replacement, it was pretty tough getting measurements from that mess. The replacement is made from a solid rubber stopper (0.95 cents at the hardware store), the 1-1/16" size, which I drilled out and filed down to the proper diameter, about 7/8". But like I mentioned, I drilled the hole too big because I thought that's what the original hole on the mangled piece measured. The rubber drills super easy, I used visegrips to hold the stopper and worked through a few drill bit sizes to keep on center. I also taped the drill bits at 1/2" for the depth, though I think 9/16" should be the final depth. Bushing made from a rubber stopper
Hollowing out bushing with file end Sorry about the contrast on the picture to the left, it's the best one I had. It shows using the round file to cut a hollow, with duct tape protecting the edge of the hole. The file end was pretty sharp and the rubber can be basically ground into dust when you go at it hard, gouging with a circular motion. In fact, the wearability of these rubber stoppers is my main concern, I wish I could have found a harder rubber to work with, but I suppose stoppers are supposed to be soft. And as pointed out before, the hole drilled in this stopper was too big, 1/2" rather than the 3/8" I later measured off the newly broken bushing. You'll see the difference with my next attempts directly below: I did the gouging out near the car and tried frequent fittings so I wouldn't overdo removing material. As soon as I could get it to sit on the ball, I stopped. The test fitting of the rubber stopper, soon to be a shift rod bushing, is shown below.
You can also see in the picture to the below that I didn't do a good job centering the holes in my second set of bushings. The reason is I skipped to many drill bit sizes going from the 1/8" pilot hole which was close to dead center. Since the rubber is soft, if you skip too many drill sizes, it's easy to end up cutting in on an angle. Too compensate, when I hollowed out a rough 1/2" ball shape with the file, as I was doing above, I tried to hollow more on the fatter side of the stopper. I should also mention that the stoppers were pretty long, around an inch, so before I even began with drilling, I cut around a 1/4" off the narrow end with a razor knife. It would have been easier to file to the final diameter if I had used the narrow end of the tapered stopper, but I wanted to make sure there would be enough rubber for a bottom lip on the bushings. Test fitting rubber stopper before shaping bushing
Two new bushings made from rubber stoppers I actually held onto the rubber stopper (below) all the time with my left hand while I was filing, but allowed it to roll a little at the same time to keep a round shape. Wore a nice blister on my left thumb before I wrapped the thumb in duct tape - is there anything duct tape cannot do? I'm working on the first on my final two bushings here, so I hadn't nailed down the technique completely. By the end, the easiest way to do these I found was to use the sharp edge of the three-sided file (triangular taper) to cut a groove all the way around the stopper at the distance I wanted from the edge to form a lip. Then go around again and again leaning the file inwards, so you end up with the right shape but humped up in the middle. After, I used the circular rasp to cut a deep groove around the middle, then filed away the remainder, going around and around, with the triangular taper.
Directly below you can see the nearly finished bushing next to a rubber stopper that's only been drilled and cut to length. I ended up needing to take some meat off the diameter of the lower lip to get it through the nylon rod end, even after lubricating generously with spit:-) The picture to the lower right shows the homemade bushing after it's been installed in the shifter rod end, right before I mount it on the ball. You can see that the extra 1/16" I gave the bushing on length, making it 3/4" instead of 11/16", came back to bite me with a gap of about a 1/16" at the top. I suppose I could have measured the area I was filing out, but I figured I could do the 1/8" lip and the 1/16" lip by eye. Hopefully, it's not a fatal flaw. I suppose I could try pulling the two joints apart and adding plastic shim washers, but they don't come apart easy at this point. The bottom left shows the test fitting the stopper before going to the work of shaping the bushing. I think it's sitting around the correct height there, it's supposed to get a soft washer underneath. Bottom right is a picture of test fitting a stopper on the ball before filing into bushing shape. Filing a bushing shape
Finsihed bushing next to rubber stopper stock Homemade bushing mounted in shifter rod end
After driving around for a hundred or more shifts, it seemed to me that the lower shift arm, the one at the end of the shifter tube, was lifting up a little from the ball. Rather than wait to see if it would pop off in traffic, I cobbed on another kludge, which should keep the whole business together for a goo while. It's 1/8" plastic from an industrial electrical box cover, with slot cut for the ball shaft. I could have done a keyhole rather than a long slot, just wasn't thinking. In any case, it when on fine (below) and I secured it with a serious wire tie at each corner and one around the outside to prevent any possibility of it backing out through the slot. The shifting is smooth as silk now, for the first time in years, so I'm hoping I'll notice it getting sloppy if the rod gets loose again. For the previous year, the only way to get first gear was to go through second and keep the shifter hard to the left (pulled towards the drive) and even then, it sometimes took multiple tries. If I had thought of it ahead of time, I would have left a little slack in the four corners at the top and run a big tie wrap through the two in the foreground (away from the upright on the shifter tube) and that secured that tie wrap around the shifter tube. Would have left no room for motion, except on the ball shaft. Custom slotted retainer plate for shifter bushing
The slotted plate installed on the linkage ball shaft Shift rod retainer bracket assembled with top plate

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