Alfa Romeo GTV6 Site: 

European Car Magazine - GTV6 Project

 

Part 7 - Shift linkage maintenance and modification

European Car Magazine - February 1996

Author - Paul Mitchell
Photos by Brendan Lopez and Paul Mitchell

   

From the day in 1981 when the GTV-6 was introduced in the United States, the most common complaint heard from the automotive press and owners concerned the shift linkage. Though a definite improvement from the predecessor of the GTV-6, the Alfetta, the linkage felt stubborn, and it took an unusually long time to become accustomed to when compared to its contemporaries. This was not expected from Alfa Romeo, which had a reputation for precise gearboxes.Certainly not from a car which set a new standard for chassis dynamics and handling in its class and came with an engine that was known for smooth and effortless power. A quick look at the GTV-6 linkage for the model years 1981-84 reveals a very simple mechanism composed of the shift lever that passes through the floor to a ball-and-socket mounting in the driveshaft tunnel, which then connects by means of a clevis to the shift linkage rod. This rod in turn simply passes down the driveshaft tunnel where it then bolts to the transaxle selector shaft. The selectorshaft is supported by a plastic bushing at the clutch housing and by a bronze bushing in the transaxle case. Outwardly, this is a very simple design with a minimum of parts to wear or break, yet that is exactly what one part does with surprising regularity. The source of the problem is the bushing at the clevis. This bushing is covered by a dust boot and tends to lose its lubricant if the boot is damaged, which it usually seems to be. Not the best of lubricants was used by the factory for this part and for the ball and socket. Also a factor is the design of the original factory bushing-a plastic bush with a metal sleeve. I have found that this is a somewhat fragile design and is certainly not up to abuse inflicted by those not schooled in the finesse required in the proper shifting of European automobiles. The proximity of the bushings and dust boots to the heat of the catalytic converter does no service to their longevity. Also, sometimes the shoulder bolt securing the clevis does not have a shoulder as wide as the clevis leaving it unsupported at one end and accelerating wear. Another bushing that can also fail is the plastic bushing at the clutch housing that supports the selector shaft. Its failure leaves the selector shaft unsupported and is noted by slight fore-aft play at the shift lever. Unfortunately, replacement requires the removal of the clutch housing, necessitating the removal of the driveshaft and exhaust system and so is neglected by some owners. There is also a bronze bushing located in the transaxle that provides primary support to the selector shaft, but its location, with constant lubrication, contributes to long life. Remember to replace it when rebuilding the transaxle though. It often has been found that the clevis bushing was already damaged when the buyer took delivery of a new car due to inadequate or improper lubrication or pre-delivery abuse. This would go far in explaining the complaints of some journalists when first driving the GTV-6 at the time of introduction-and anyone familiar with press pool cars would have to agree. The 1985 GTV-6 and Milano came with an entirely redesigned linkage that eliminated this problem. Essentially the same at the shift lever down to the clevis, which was now wider to provide more lateral support to the new all-metal bushing, the latter part of the linkage rod now acted upon a modified parallelogram, which in turn actuated the selector shaft. This new design provided substantially better feel with shorter throws. How much of this improved feel was due to the wider clevis and new bushing or to the parallelogram is unclear. What is clear is that the new system has its own flaws, though none seem to generate the vitriolic complaints of the old layout. When the new system becomes worn, all the plastic bushings within the parallelogram must be replaced. There are four viable options when trying to remedy the shift linkage problem. All will, to one degree or another, correct the problem. I will list them here in order of expense and include installation procedures at the end of this article. When performing any of the listed options, replace the shoulder bolt at the clevis with a grade 8 shoulder bolt. Secure with a self-locking nut, and be sure to use a washer.

 

Above: the linkage for the early GTV6;

Below: linkage for a 1986 GTV6 complete with clevis boot

Pre-86 GTV6 shift linkage with selector shaft mount. Much more simple than the later linkage

The factory clevis bushings and bolt. Note that the clevis bolt is not as wide as the bushing. Replace with appropriate hardware.

The plastic bushing at the clutch housing.

 

Option #1

Replace the faulty bushing with an OEM replacement. At this time the dust boot should also be replaced. The bushing should cost approximately $8 and the dust boot $10. Both are available through your dealer or independent distributor such as AR Ricambi. This will restore the original shift quality, but should only be considered a temporary fix, as even with improved higher-temperature grease and a new dust boot, the bushing will fail sooner than in the following options. Think of the OEM bushing as a wear-related item, such as brake pads or a clutch lining.

 

Option #2

Take the measurements off the OEM bushing and have a machine shop fabricate a replacement out of a more durable material such as bronze or Delrin (I prefer bronze). The price will vary with the shop and the material chosen, but should still be quite reasonable. I will include the measurements of the factory bushing at the end of this article for anyone who chooses to make this worthy modification.

 

Option #3

Install a Shankle Sure Shift, an entire lever and linkage available through AR Ricambi for approximately $100. The new lever has revised geometry, providing shorter throws, and the clevis incorporates a stronger bronze bushing. Many have used this modification to achieve smooth, precise shifting.

 

Option #4

Retrofit the entire shift linkage assembly, including the lever, rod, parallelogram and selector shaft from a 1986 GTV-6 to your earlier GTV-6. Keep in mind that this will also necessitate a small amount of floor pan modification, usually with a hammer (though some have fabricated a new small section to allow clearance), and opening up your transmission case to install the selector shaft. The entire assembly is available through Alfa Parts Exchange as a kit for approximately $100 to 150. This is the most involved and expensive of all the options in this article, but it provides the satisfaction of knowing you've used the factory method to correct the problem. We used the third option, the Shankle Sure-Shift kit, on our project GTV-6 and found it provided excellent results. Available through AR Ricambi, the kit is certainly one of the easiest of all the modifications to install and offers the security of thorough development. At $110.00, we found it to be a bargain and a very worthy modification. As mentioned before, all of these options will correct the problem of difficult, imprecise shifting. Your choice should be dictated by your budget and the amount of time you want to spend under the car.

 

Tech Procedures

The following procedures are required to undertake all modifications listed above. Further instructions specific to each modification will be included as noted. The only tools required are standard hand tools, including sockets and box-open wrenches. The machining required for option #2 can be performed by any competent machine shop or can be undertaken by the reader who possesses a lathe. If using a bronze replacement bushing, an old racer's trick would be to cook the bushing at 250 degrees in single weight motor oil for four hours in a pan on the stove. Many believe that this permanently lubricates the bushing. This can be performed on any bronze bushing, such as a pilot bearing.

  

 

 

Instructions for All Options

Remove the catalytic converter by loosening the two 13mm nuts at each head pipe and the clamps fastened by 13mm bolts at the center muffler. Also unfasten the brace supporting the catalytic converter to the rear motor mount.

Remove the heat shield and pull back the dust boot covering the clevis. Unfasten the bolt securing the clevis pin and extract the pin.

If performing options #1 or #2, extract the original bushing and install the new bushing. Be sure to lubricate liberally with a quality high temperature bearing grease. Slip off the original dust boot and slip on the new dust boot.

Reassembly is the reverse of disassembly.

To continue with options #3 and #4, continue by removing the shift knob. This is best accomplished by pulling upward strongly with a twisting motion. Back under the car, unfasten the bolts securing the shift lever assembly to the body and remove it downward. Unfasten the bolts securing the linkage rod to the selector shaft at the transaxle and remove the rod.

 

The lower half of the gear selector lever, including its mounting. Space here is in short supply.

A complete 1986 GTV6 linkage assembly fitted to a transaxle

 

Option # 3: The Shankle Sure Shift comes with complete instructions; they essentially contain the following: Remove the original shift assembly as per instructions above and install the new components in a reverse manner.

Option # 4: Having a factory service manual available is advised to carry out the following procedure.

Materials required:
Transaxle lubricant, selector shaft bushing and dust boot at clutch cover. Selector shaft bushing in transaxle. High-temperature grease.
At this time, you may want to consider replacing the driveshaft flex couplings and center support bearing. If so, also replace the driveshaft pilot bearings.

 

  • Remove the original shift linkage by following above instructions. With the rear of the car lifted also, drain the oil from the transaxle. Remove the center muffler.
  • The driveshaft must be removed. At the front of the driveshaft, loosen and remove the 17mm nuts securing the flex coupling to the front flywheel. Next, loosen the nuts securing the rear of the driveshaft and flex coupling to the transaxle input shaft flange. The center support bearing of the driveshaft may now be unbolted and the driveshaft removed from the car. You may find it necessary to lever the flex coupling to free it from the flange or flywheel, and a large screwdriver or pry bar will work fine.
  • Support the rear crossmember with a jack, then loosen and remove the bolts retaining the rear crossmember to the body. Gently lower the jack a few inches; the front of the transaxle will be lowered as well. Take care not to stretch the flexible line of the clutch slave cylinder.
  • Loosen and remove the bolts securing the clutch cover to the transaxle.
  • Remove the clutch assembly. At this time renew the selector shaft bushing and dust boot, both located on the clutch cover. Be sure to lubricate the bushing with a high-temperature, long-lasting grease.
  • Remove the selector shaft and renew the selector shaft bushing in the transaxle housing. Install the newer selector shaft and reassemble using the reverse of the above procedures.
  • Install the new parallelogram and carefully raise the front of the transaxle, note where on the body the parallelogram will hit, and gently relieve this area with a mallet. Raise the transaxle again and reassemble the driveline and linkage assembly in the reverse of the above disassembly instructions. Refill the transaxle with lubricant.

 

Dimensions of Factory Clevis Bushing
Outside diameter: 12 mm
Inside diameter: 7 mm
Length: 15.1 mm

 

The selector input shaft at the transaxle. This '86 type must be installed to retrofit later type into pre-'86 GTV6's

Another close-up of the articulated linkage assembly off the transaxle

Close up of the articulated assembly of the later type linkage.