Manual Transmission Shifter Basics

Today most manual-transmission cars are equipped with a floor shifter. In general, prior to World War II, most vehicles had a shifter mounted in the top cover of the transmission. The shifter directly moved the shift forks. Automotive engineers in Detroit wanted to get away from floormounted shifters and create shifters built into the steering column. In order to create a column-mounted shifter, the actual transmission shift mechanism now had to have a series of external shifter shafts, linkage arms, shift rods, and levers for this design to be feasible. These new components required a redesign of the actual transmission to incorporate the addition of all these extra components.

 


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The column-shifter design was a far cry from the positive feel of the direct-top cover shifter. To provide that positive shift feel, modifying column shift back to a floor shift became the thing to do when drag racing started to flourish in the late 1950s. Drag racing puts a tremendous strain on linkage components, and a common modification was usually a custom floor shifter. Companies, such as Fenton, Sparkomatic, P&G, Hurst, and Mr. Gasket, were leaders in this field. The typical “H”- pattern shifter seems to have stood the test of time. The H-pattern design, for the most part uses a horizontal gate. Thus, the shifter moves left or right to grab each gate.

 

This is the first sequential-style shifter design made for a side-rail-shifted transmission. The driver pulls one lever for upshifts and another for downshifts.

This is the first sequential-style shifter design made for a side-rail-shifted transmission. The driver pulls one lever for upshifts and another for downshifts.

 

Bill Bieber is the person credited with the design of the Vertigate Shifter. The gates were set up in a vertical alignment. This eliminated the need to move the shifter left or right. You just pulled the stick front to back to change gears. He also created a wild shifter, called “The Changer,” which had two sticks. One was for upshifts and one for downshifts. You just pulled the sticks toward you to change gears. It used a huge rotating cam on the side cover.

 

Thin stampings and cast-aluminum bodies made these early hot-rod-style shifters very weak.

Thin stampings and cast-aluminum bodies made these early hot-rod-style shifters very weak.

 

The Hurst Competition Plus shifter improved on all previous designs, and it’s still one of the best aftermarket shifters.

The Hurst Competition Plus shifter improved on all previous designs, and it’s still one of the best aftermarket shifters.

 

Hurst Shifters have a vast number of installation kits for just about every side-mounted 3- and 4-speed shifter.

Hurst Shifters have a vast number of installation kits for just about every side-mounted 3- and 4-speed shifter.

 

Most of these designs suffered in the durability department, as well. The very popular Fenton and Sparkomatic incorporated die-cast aluminum bodies in some models, which quickly cracked under heavy use. The radically designed Changer required a huge portion of your floor pan to be cut out. Hurst and Mr. Gasket were the only two companies to survive the “shifter wars.”

Various patents were issued protecting most of these unique shifter designs, and therefore only a handful of aftermarket companies specialized in this field. Today, things are much different. The T5 transmission has a multitude of companies making replacement shifters, and almost every high-end manufacturer has its own shifter.

 

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The Need for Shifters

All conventional factory linkagestyle shifters lack the use of a stopping mechanism. For normal applications a “stop” may not be needed. When the “stop” isn’t present, the force of your shift is stopped internally by the detents of the transmission. This leads to premature failure of shift detents, shift forks, or shift lugs. The stopping device is usually a bolt that is adjusted to absorb the force of the shift, thus extending the life of the internal components. Improvement of shift “feel” is another important upgrade you should expect from a high-performance shifter. Usually they are designed to decrease travel lengthwise (short throw) and sometimes narrow the H-pattern. Others may incorporate a better left and right bias of the shifter.

 

Here is a Long HN-1000 H-Pattern shifter designed for a Cobra kit car and bolted to a Richmond 5-speed.

Here is a Long HN-1000 H-Pattern shifter designed for a Cobra kit car and bolted to a Richmond 5-speed.

 

The Long HN-1000 uses rails that run parallel with one another and in a straight line, as opposed to the Hurst shifter that has the gates move in an arc within the shifter body.

The Long HN-1000 uses rails that run parallel with one another and in a straight line, as opposed to the Hurst shifter that has the gates move in an arc within the shifter body.

 

When it comes to road racing, Mid Valley Engineering’s Shur Shifter is hard to beat. The whole mechanism is in a sealed housing. Basically, internal rails shift many transmissions, and the Shur Shifter can turn any externallinkage- designed transmission into a rail-shifted type with built-in stops and interlocks.

When it comes to road racing, Mid Valley Engineering’s Shur Shifter is hard to beat. The whole mechanism is in a sealed housing. Basically, internal rails shift many transmissions, and the Shur Shifter can turn any externallinkage- designed transmission into a rail-shifted type with built-in stops and interlocks.

 

This is Long Shifters’ high-tech verticalgated shifter. By pulling the lever up, the shifter is positioned with the top gate. Releasing the lever allows the springs to pull the shifter’s arm vertically down each gate and eliminates the need for a conventional H-pattern.

This is Long Shifters’ high-tech verticalgated shifter. By pulling the lever up, the shifter is positioned with the top gate. Releasing the lever allows the springs to pull the shifter’s arm vertically down each gate and eliminates the need for a conventional H-pattern.

 

Jerico Transmission’s air shifter has solenoid valves that route a high-pressure volume of air from one passage to another. A push-button actuates each shift, and a dial selects neutral or reverse.

Jerico Transmission’s air shifter has solenoid valves that route a high-pressure volume of air from one passage to another. A push-button actuates each shift, and a dial selects neutral or reverse.

 

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The dotted line shows the path your 1/4-inch-diameter rod should take. The circle shows how the gates are aligned, but as you can see, they are not centralized within the shifter body. This is the only other way a shifter can cause a transmission to fall out of gear with a good neutral gate.

 

The factory GM Muncie 4-speed shifter had no spring mechanism in the shifter other than to lift the reverse lock-out rod. Since it could flop left or right, it was clumsy to speed shift. You never knew the actual location of the shift gates.

The Hurst Competition Plus design has stood the test of time. It has a perfectly designed bias that keeps the handle in the 3-4 gate, so it aids you when going from second into third during speed shifting. It has an additional spring force to overcome when engaging reverse, eliminating reverse lockout levers. GM actually started to install these shifters in the 4-4-2 and GTO.

Sometimes in drag racing, the speed of your shift can make the difference between a win and a loss. These shifters were designed to create rapid shifts without the possibility of a “missed” shift.

 

Fixing the Hurst Competition Plus Shifter

There are more Hurst Competition Plus shifters floating around used and new than any other shifter around. By now, cleaning out the older units may be needed. These shifters, if properly maintained, never wear out. Hurst still sells typical bushings and clips in what they call a Pit Pack.

Oddly, many people don’t understand what shifter adjustment will and will not do. There are only two adjustments that can be made with any conventional Hurst Competition Plus shifter. The first is a neutral gate adjustment, and the second is stop adjustment. If your transmission is falling out of gear and you have a good neutral gate (a clean left-to-right motion of the shifter), you can’t turn any rods to eliminate that problem. Stop bolts can become loose and work themselves in too far. If the shifter falls out of gear, remove the stops and see if this resolves the problem. To align these shifters a 1/4-inch rod is pushed through the shifter body and the three gates. The rod aligns the gates with each other and centralizes the gates within the shifter body.

 

T5/T56 Shifter Modifications

The factory T5 shifter is simply a lever that pivots on a ball socket. Side-to-side and forward-to-backward motions both ride on this ball socket. The centerline distance of your pivot-ball socket to the level end centerline determines the length of your throw. Until 2004, every aftermarket T5 shifter used the same principle. They just housed them differently, or used their own variations of bias spring pressures to come up with their own feel.

McLeod Industries’ Red Roberts designed a pivot system using a vertically mounted spherical bearing.

 

Modifying a Hurst Competition Plus Shifter

 

Step 1: Pry Apart Shift Body

11With all the bolts removed, use a pair of drift punches and pry the shift body apart.

 
 
 
 
 

Step 2: Unbolt Back Wall

12Remove the back wall of the shifter body.

 
 
 
 
 
 

Step 3: Remove Main Pivot Shaft

13Remove the main pivot shaft by tapping it out or walking it out with a set of pliers.

 
 
 
 
 

Step 4: Remove Gate Assembly from Shifter Body

14Grasp the whole gate assembly and pull it out of the shifter body. Try to keep it together.

 
 
 
 

Step 5: Inspect and Clean All Parts

15Once out of the shifter body, carefully lay down each piece. You may want to clean each piece and return it to its proper place on the bench.

 
 
 

Step 6:Verify Shifter Body Operation

16The plunger (1) basically contacts all three gates depending on how the shifter is biased left or right. The internal stop (2) is what gives you the extra effort to get into reverse. The spring (3) handles the normal left-toright bias. The circle shows the roll pins that push the plunger left or right. The pin on the left broke, allowing the stick to move toward first gear, but not the plunger.

 
 
 
 

The Slik Stix shifter’s design creates a very efficient geometry that produces shorter throws and narrower gates within a smaller package.

The T5 shifter is the most reproduced aftermarket shifter today. When it comes to the factory T5 shifter, there are no adjustments because it has only one internal shift rail, and an internal transmission track plate controls neutral. It becomes a shifter with very few components.

Hurst originally came up with a cast-alloy low-profile, short-throw shifter for Ford’s SVO program. The shifter sparked interest from several companies to create billet shifters that didn’t wear out as quickly. These sport billet-machined bodies with stop bolts. The stops keep the internal shift lugs from deforming under heavy load. Because factory T5 shifters are a non-serviceable item, I will show you how to modify the factory shifter for any specialized conversion you may have in mind.

 

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Modifying the T5/T56 shifters in this manner makes for a clean-looking piece as opposed to some stick that is bolted on and spaced out in every direction possible. It also makes for a better-shifting assembly because the geometry is much more direct.

Step 7: Replace Roll Pins

17Replace the factory roll pins with solid, hardened pins available from any machine tool supply house. This is basically the only trick modification that needs to be done. Everything is cleaned. Reverse the above steps to assemble the shifter.

 

18The lowprofile shape of the McLeod Shifter also allows for many offsets without creating floor pan interference.

 
 
 
 
 
 

19A stock T5 GM-style shifter is shown on the left, and a billet Steeda Tri-Ax shifter appears on the right.

 

 

20Notice how the McLeod shifter uses a spherical bearing. This eliminates the need to keep the pivot loaded, prevents pivot wear, and allows for total spring bias adjustment with Bellville washers.

 

 

21Here is a wide variety of factory shifters that I keep to mix-and-match parts for various conversion projects.

 
 
 
 
 
 
 
 

Customizing a Stock T-5 Shifter

 

Step 1: Cut Off Folded Section

22Start to dismantle the T5 shifter by cutting off the rear folded section. Unfolding it and refolding will only weaken it, so just cut it off.

 
 
 
 
 
 

Step 2: A) Disassemble Shifter Assembly

23Tap the cover rearward with a hammer, and the whole shifter will come apart. Lift the stub assembly out of the socket base, and remember the order of the flat springs. Slide off the nylon ball.

 
 
 

B) Short-Throw and Normal-Throw Shifters

24A normalthrow shifter stub is on the left, while a short-throw stub is on the right. They are the same length, but the position of the pivot shaft is higher on the short-throw version. The base is also higher on the short-throw shifter. You cannot mix bases and stubs, meaning a short-throw base stays with a short-throw stub.

 
 
 
 
 
 

Step 3: Weld On New Shifter Fitting

25Now start welding since all plastic parts and springs are removed. I’m welding a special fitting for my JT5 Jaguar shifter.

 
 
 
 
 
 

Step 4: Create the Necessary Offset

26The fitting creates the proper offset any angle for my conversion. You can do the same for any other conversion. The concept is the same.

 
 
 
 
 
 

Step 5:Assemble Shifter

27Assemble the shifter with all internal components greased. Clamp it together in a vise along with some Vise-Grips clamping the top half together with the base. It acts as a heat sink while the two halves are fuse-welded together. If you make a really long stick, add a couple of extra flat bias springs to get a better bias feel. Shifter internal parts are not available, so that is why I keep lots of shifters around.

Step 6:  Install Shifter Handle and Boot

28The fitting I weld on allows me to screw on my own custom stick, shift ball, and locking ferule.

 
 
 
 
 

 
 
 
 
 
 

Written by Paul Cangialosi and Posted with Permission of CarTechBooks

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