L-body Shift Linkage Repair
or, how to stop rowing through a bucket of oatmeal
written by Stefan Mullikin
Omni's are fun cars, but even new the shifting leaves a little to be desired. The combination of flex prone transaxle case, rubber motor mounts and shift linkage that was partially mounted to the K-frame equaled a lack of shifting when you were pushing it. They improved this on the turbo cars starting in 85 and in the non-turbo cars in 87 by separating the linkage from the chassis and mounting it all to the transaxle. Now your shifting was really only limited by issues with the transaxle, though the rubber mounts could cause you to miss a shift in a corner since the motor will move side to side and the shifter will move accordingly potentially causing the driver to move the shifter to the wrong spot, confusion and missed shifts then ensued.
Now, with the above in hand, add a few years to the cars and you get really worn out mounts, brittle and worn out plastic shift linkage joints which can pop-off if you look at them funny and potentially unhappy Omni drivers. Chrysler again instituted a solution (albeit cheap) with a series of metal clips to physically hold the plastic joints together. These are pretty cheap from the dealer and aren't too hard to install. Now, you'll still have the same old sloppy joints, but at least they don't come apart anymore.
Before this happened on my Rampage, I decided to fix this permanently. I upgraded the linkage to the 87 and later linkage and then installed metal rod ends fastened with bolts and nuts to replace the stock plastic rod ends. A couple of vendors over the years have offered this conversion, but at this time I don't know of any who do anymore. Probably because by now most people have replaced the worn parts with new stock pieces from the dealer or they installed cable linkage from a Daytona/Shadow. I still prefer the mechanical linkage myself and it also allows me to use my Hurst Shifter.
The conversion is relatively easy to do. The hardest part is removal and install of the linkage as the L-body engine bays are tight and after a few years rust can set in further adding to the complications. The improvement to the feel of the shifting is well worth it, however you still have the physical limitation of the A-525 transaxle to deal with, but that's another issue entirely. I will say that I have successfully built a couple of brackets for the 520/555 to use the L-body linkage. The bracket also solves the rear dogbone mount issue the newer transaxle creates. I'll cover building that in another article.
One thing to note about this conversion is that if you're syncro's, shift rails, shift forks or gears are worn out, you'll find this will make those issues more obvious to you as the shifting will be even more notchy. My feeling is that a freshening of the transaxle with a differential girdle, a Chrome-Moly third gear bearing retaining plate and a limited slip differential with decent fluid should be automatically done by anyone still running an A-525/460 or 465 in competition and/or behind a turbo motor. Even then its life will can be somewhat short, especially if you pound it, force the shifts, drive it hard before it warms up, never change the fluid, let it run low on fluid, etc.
Parts You'll Need:
- 3/8" Female Rod Ends (4)
- 3/8" Male Rod End (1)
- 3/8"x1-1/2" Bolts (5)
- 3/8" Nylock nuts (5)
- 3/8" jam nuts (5)
- 3/8" rod end/cone washers (10)
Optional Parts:
Turbo or 87 and later linkage for cars with older style linkage. Grab everything, including the bracket on the back of the transaxle.
- (1) 10mm male rod end, bolt, nut and washers to replace the helicoil, the 3/8 male rod end and one of the 3/8 bolts, nuts and two washers. You'll need to drill the hole in that joint to 10mm bolt not a 3/8" bolt
- (4) 1/2" x 3/4" x 3/4" Bronze bushings to replace the nylon bushings in the pivots.
Tools You'll Need:
- Drill or drill press
- Various drill bits up to 3/8"
- 3/8" helicoil kit
- Grinder or cut off wheel
- 3/8" tap and dye
- Vise
- Pliers
- 9/16" wrenches or sockets and ratchets
Build
Remove the linkage from the car. This includes the shift tube, the two pivots and the bracket attached to the gear selector on the transaxle. The pivot arms are held in place with a pair of E-clips. The gear selector bracket is attached using a 13mm nut. Be careful to keep track of what goes where to minimize confusion later.
Depending on how good you are with a drill or if you have access to a drill press you can drill through the center of the metal balls on the pivot arms with the 3/8" drill bit (be sure to step up to 3/8" to reduce work on the drill bit) Otherwise I would recommend cutting or grinding off as much of the pivot balls as you can then drilling them out.
If you want to get fancy and use left and right threaded rod ends, then you'll need to have the appropriate left and right hand dyes and two left and two right hand threaded female rod ends and jam nuts.
The rods are relatively easy to modify, just make note of the center to center distance and the orientation before removing the plastic ends by snapping them off with a pair of pliers or a vise. Thread the ends using the 3/8" dye, be careful to get it started straight and to go slowly with cutting oil, stopping every quarter turn and backing up at least a full turn to keep the threads clean so they don't get rounded.
Thread the rod ends and the jam nuts on the rods, paying attention to the orientation of the rod ends and the center to center distance. Tighten the jam nuts and rods together to lock them into place. Install the bolts through the arms, place a cone washer on top followed by the rod end another washer and finished with a nylock washer. I use better grade bolts that are only threaded partially to ensure the rod ends are working against a smooth shaft that is 3/8" in diameter not the slightly smaller diameter of the threaded portion of the bolt.
When you get to the joint for the male rod end, its already threaded for a 10mm joint. You can choose to drill it and use a 3/8-24 helicoil or find a 10mm rod end, bolt, nuts and washers. Your choice as either way works, just e sure to drill the hole for the through bolt with the appropriate sized drill as a 3/8" hole would be slightly too big for a 10mm bolt.
If you choose to replace the pivot bushings, you can use some bronze bushings as I have. You can also use Polyurethane or even sealed bearings, you're choice. The Bronze bushings cost me about $0.25/ea. The new pivot bushings helps firm things up even more, with the addition of a little more vibration in the shifter. To do this you'll need to bore the pivots out or turn the bushings down to fit the holes in the pivots as they were ovaled during manufacture (the hole was cut into the pivot then it was bent, stretching the holes slightly) You can also use similar bushings in the bottom of the shifter, just be prepared to have a lot more vibrations in the shifter. John at Polybushings.com has generic sized polyurethane bushings available that might also work to dampen some of the vibrations but still provide firmer action.
Install
Installation is the same as removal. If you use bronze bushings for the pivots you might need to pull the shafts they pivot on to clean them up as they can get pretty gunky over the years. You might also need to file the face of the bushings down to allow the E-clip to fit and not bind the bushing up.
Make sure all of the bolts and nuts are tight. Follow the procedures in the manual for adjusting the linkage. You'll notice right away that you can be much more precise with the adjustment than before. You'll also probably notice that the joint that the shifter itself runs through has worn out a little along with the reverse lock out spring. If you're a decent machinist you can disassemble the shifter and bore the joint slightly for a bushing. While you're at it you can also shorten the throw by moving the shaft farther down and replacing the spring with a new one. Just make sure to space the reverse lockout tin lower to accommodate the shifter sitting lower.
Finish
Here are some pictures of a completed linkage setup I did for my friend, Anna and her 85 Shelby Charger. It was the first set I had done, the second is on my Rampage and the third is on my Dad's 86 GLH-T a fourth is in Hawaii on another GLH-T. Hopefully I can help others with this information and/or provide modification services to those who don't have the facilities to perform these modifications on their own.
Stefan Mullikin
Co-Founder
PNW-SDAC
http://www.pnw-sdac.org
1980 Fiat X-1/9
1984 Dodge Rampage 2.2
1987 Plymouth Sundance Turbo
1987 Shelby CSX #106
1988 Shelby CSX-T #3
Originally Posted by Putter
Frank Katzenberger
