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Do-It-Yourself Projects
4-Speed Shifter Tech Tips
By Dave Anderson/autoMedia.com
Printable version
Degree of DifficultyModerate
Moderate
Estimated Time240 minutes
240 minutes
Shift Stops
Well, how do you inhibit this wear from reoccurring? Make certain that your shifter is adjusted properly. Unfortunately most of the Competition Plus shifters installed in our Pontiac did not come with this capability: shifter stop bolts. Hurst gave the "shade tree" mechanic a head start that makes the addition of shift stops easily achieved. The shifter body has holes stamped front and rear in the proper place to be used as pilot holes. With the proper safety equipment, just drill, tap and install a 3/8-inch bolt and jam nut and you have added the shift stops.
 
With the shift stops installed it is time to reassemble the shifter linkage and adjust the shifter. This includes the tightening up of the earlier identified shift rod rattle. When making your trip to the hardware store for the 3/8-inch bolts and jam nuts for the shifter stops, you will also need to pick up a few new lock nuts and hardened washers, both flat and spring wave. You should have noted in your disassembly of the shift rods from the transmission levers that a spring wave washer was used to take up some slack. Over the years the spring gives way and the "some slack" turns into a lot of slack. We found these new heavier spring wave washers in the metric section at our neighborhood Ace Hardware.
 
Reassembly
Install the levers back onto the transmission with the new lock nuts and hardened washers, being careful to not over-tighten the nuts. With a standard length wrench, you can easily put 15-20 lb.-ft. of torque on these. Next install the shift rods to the levers using the new spring wave washers. Do not tighten these up just yet. That is done during the final adjustment process.
 
Now affix the other end of each shift rod to the shifter levers. Before you install the spring clips, add a hardened washer to take up the slop. After you install the spring clips, take needle-nose pliers and bend up the ends of the spring clips. This will ensure the spring clip stays in place. Put the shifter into Neutral and slide in your alignment tool.
 
With the shifter in Neutral and the transmission in Neutral, tighten the nuts where the shift rods attach to the transmission levers. Remove the alignment tool and firmly shift through the gears. Return to the Neutral position and you will see that your alignment tool falls right into place.
 
Ready, Set, Go
The final operation is to set the shift stops. This is easily done, but one would be surprised at the number of shifters (with adjustable stops) that are improperly adjusted. First, make certain the stops (bolts) are backed out. Place the transmission in 1st gear then firmly shift down into 2nd gear. Tighten the stop bolt until it touches. Then back the bolt out one complete turn and tighten the jam nut. Repeat the procedure for the other stop by placing the transmission into 3rd gear. You'll now have firm positive shifts.
The Muncie M-20 wide ratio 4-speed transmission equipped with the Hurst Competition Plus shifter. The shift rods were loose. After inspecting the linkage, it was time for disassembly. Note that there are no shifter stops on this factory-installed shifter.
Muncie M-20 Wide Ratio 4-Speed Transmission Equipped with the Hurst Competition Plus Shifter
Here is the worn forward shift lever removed from the transmission. You can see the spread area caused by numerous hard 1-2 power shifts. This increased interior dimension can result in the transmission detents not returning to Neutral.
Worn Forward Shift Lever Removed from the Transmission
With the damaged area brazed to fill the spread/worn area, hand file the shift lever back to its original size. Take your time, file and test-fit the lever until you have it right and tight being careful to not remove too much of the material.
Hand File the Shift Lever Back to its Original Size
File fit back to its original interior dimensions, the shift lever is ready to be installed.
Filed Shift Lever is Ready to be Installed
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