Gearstar transmissions are assembled by one technician from start to finish using the best
Like many street rods, our AMSOIL/STREET RODDER Road Tour '09 Chevy is equipped with an automatic transmission. But instead of the two-speed cast-iron Powerglide that was original equipment in `52 we're slipping in a contemporary 4L60 from our friends at Gearstar.
Just about everyone realizes the advantages of an overdrive automatic and that Gearstar can provide a transmission tailored to your specific needs. So, all you have to do is pick up the phone, tell them what you want and when the crate arrives bolt the new transmission in place then hit the road, right? Well, sort of. Installing an automatic transmission isn't a particularly complicated job, however there are some procedures that should be followed. Just like everything else, there's a right way and a wrong way to do it.
Hopefully it goes without saying that the car should be on a hoist or properly supported on jackstands before installation begins. And while some of us like to recall the things we could pick up and carry in our youth, the days of putting a dinky little three-speed transmission on your chest and hoisting it into position are long gone. In any case, buy, borrow or rent a proper transmission jack. But before you and the transmission slide under the car, here are a few things Gearstar suggests you do.
Thoroughly inspect the back of the engine. Make sure the mating surface is clean and not damaged in any way. Remove any paint from the mounting surface and use a file to knock down any high spots caused by nicks in the block. Check to ensure the dowel pins protrude from engine block 3/8-inch of an inch, not including the tapered portion of the pin; they should also be free of paint or gouges (remove and replace the pins if necessary). Check the condition of the threaded holes in the block, look for cracks or stripped threads and repair any damaged threads with thread inserts. Finally run a tap through all the holes and blow them out with air.
The flexplate should new or in perfect condition. Make sure it is matched to the balance of the engine (some externally balanced engines require weight on the flexplate) and that it is oriented correctly (the raised lip on the center register faces the transmission). Only the proper bolts with shoulders under the heads that precisely fit the holes in the flexplate should be installed. Depending on the type of bolts used, star type lock washers or thread locking compound will be required, torque the bolts to the engine manufacturers specs. Do not use vice grips or anything other than the appropriate flywheel turner to spin the engine. Clean out crank pilot with emery cloth or a rotary wire brush and lube with light coating of chassis grease.
Besides the transmission and Yank converter, the Gearstar crate delivered to Woody's Hot R
With the transmission secured to the jack, remove converter retainer bracket (used to hold the converter in place during shipping) raise transmission to block taking care not to pinch wiring harnesses and/or cables between transmission and engine.
One of the critical steps in transmission installation is making sure that the torque converter does not contact engine flexplate before transmission bell housing contacts engine block, if it does the converter is not seated in the transmission. Never use the bellhousing bolts to pull the transmission against the block if the torque converter and flexplate are in contact with one another, damage to the transmission's pump will likely result.
Once the bellhousing contacts block install one bolt on each side simultaneously (use at least Grade-5 bolts without lock washers). Make sure there is no more than -inch and no less than 1/8-inch clearance between flexplate and converter pads and that the converter spins freely. You can then install the remaining bellhousing bolts and torque them all to 45 ft-lb. and install the torque converter bolts with medium strength thread locker, torquing them to 35 ft-lb.