European Car Magazine - GTV6 Project
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Alfa Romeo GTV6 Site: European Car Magazine - GTV6 Project |
European Car Magazine - February 1996
Author - Paul Mitchell
Photos by Brendan Lopez and Paul Mitchell
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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.
Option #1Replace 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 #2Take 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 #3Install 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 #4Retrofit 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 ProceduresThe 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 OptionsRemove 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.
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:
Dimensions of Factory Clevis Bushing
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