Gearstar Level Two 4L60E - Transmission - Hitting All The Gears

Gearstar 4L60e Transmission Hitting All The Gears Transaver Plus

Popping open the shipping crate revealed not only the Gearstar 4L60E, but also a Hayden auxiliary transmission cooler and enough Castrol Dex/Merc fluid to top off the transmission.

Popping open the shipping crate revealed not only the Gearstar 4L60E, but also a Hayden au

There are many mechanical sounds that have a certain way of crawling right into your head and releasing thoughts of dread and dismay. Those kinds of sounds signify that your day, week, or possibly month is in complete ruin. There seems to be a direct correlation between the emanating sounds and your wallet. It’s like they’re somehow connected to each other, causing your credit cards and hundred dollar bills to shake uncontrollably. We felt that exact wallet shake and feelings of dread when our ’02 Chevy Avalanche began to show signs of finally calling it quits. Trying to get moving from a stop was an exercise in frustration as the engine would rev, but the transmission wouldn’t allow much forward momentum. After a week of slipping, the 4L60E had enough of our abuse and decided to leave the SUT stranded awaiting a tow truck to come to the rescue.

Gearstar 4L60e Transmission Hitting All The Gears Driveshaft Removed

1. Arriving at The Transmission House in Covina, California, a number of large items needed to be removed to allow enough room to drop the transmission from the Avalanche, beginning with the driveshaft.

1. Arriving at The Transmission House in Covina, California, a number of large items neede

You may remember the truck from a previous issue as we pulled the high-mileage (read worn-out) 5.3L from its engine bay and replaced it with a new LS327 crate engine from GM Performance Parts. Things have gone swimmingly since then, but mileage takes its toll on parts and our original automatic transmission was knocking on 160,000 miles. To replace our ailing unit we called the crew at Gearstar transmissions in Akron, Ohio, and ordered the company’s Level Two 4L60E. In it, Gearstar fits all new wiring and solenoids, a Corvette servo designed for more power, high capacity 10-vane pump, better bands for the shift drums, a TransGo shift recalibration, and many other parts to ensure its transmission lives up to the reputation Gearstar has set. It even comes with a furnace-brazed torque converter for stalls between 2,200 and 2,400 rpm. Rated for duties up to 450 hp and 425 lb-ft of torque, the Gearstar 4L60E will be a perfect complement to the 327hp LS327 we nestled under the hood. Doing the transmission two-step while we snapped the picks was The Transmission House in Covina, California. Once up on the vehicle lift, the guys handled the swap in no time at all and made everything go so easily.

2. Using a tall, threaded screw jack, the worn-out and slipping transmission was supported, as its crossmember was unbolted, removed, and set aside.
2. Using a tall, threaded screw jack, the worn-out and slipping transmission was supported
3. Blocking the way out was the exhaust Y-pipe, so it was also slipped free and placed nearby.
3. Blocking the way out was the exhaust Y-pipe, so it was also slipped free and placed nea
4. Being a computer controlled unit, a number of external electrical harness plugs were disconnected along with unbolting the gear selector switch.
4. Being a computer controlled unit, a number of external electrical harness plugs were di

5. The starter's electrical was disconnected, and the unit was unbolted and set aside.
6. On newer transmissions, there is no longer a removable cover to allow access to the hardware connecting the torque converter to the flexplate. An opening in the bellhousing allows a turning tool to slip inside and rotate the flexplate until each of the three bolts can be accessed and removed.
6. On newer transmissions, there is no longer a removable cover to allow access to the har
7. The screw jack was replaced with a hydraulic transmission jack, and the whole unit dropped free once the nine bolts mounting the bellhousing to the block were broken free.
7. The screw jack was replaced with a hydraulic transmission jack, and the whole unit drop

8. One area that is often overlooked is the transmission lines flowing through the factory cooler. With mileage such as ours, oil residue and clutch band particles can build up over time and get trapped. The Transmission House knew this and hooked up a machine to pump cleaner throughout the system and back flush the lines.
8. One area that is often overlooked is the transmission lines flowing through the factory
9. With no reason to wait around, the Gearstar replacement 4L60E was set on the jack to prepare for its launch into the underbelly of the Avalanche.
9. With no reason to wait around, the Gearstar replacement 4L60E was set on the jack to pr
10. A little finesse was applied in lining up the bellhousing to allow the attachment bolts to be started by hand. Our original transmission isolator mount was wasted so, as you can see, The Transmission House supplied us with a fresh one.
10. A little finesse was applied in lining up the bellhousing to allow the attachment bolt

11. With everything supported, but a little loose, the small cache of parts on the floor was mounted back onto the truck beginning with the engine’s starter motor.
11. With everything supported, but a little loose, the small cache of parts on the floor w
12. All the bolts holding the bellhousing to the block were tightened accordingly, and the new, higher stall torque converter was attached to the flexplate with the specialized factory bolts.
12. All the bolts holding the bellhousing to the block were tightened accordingly, and the
13. While there was still plenty of room to work, the gear selector switch and the rest of the electrical connectors were put into final position on the transmission’s case.
13. While there was still plenty of room to work, the gear selector switch and the rest of

14. After heating the Y-pipe into place and reattaching it to the Magnaflow after-cat exhaust, the whole exhaust system received a wipe down with cleaner to remove the dirty hand prints. We did not want that fresh oil and grease to get hot and start burning and smoking upon startup.
14. After heating the Y-pipe into place and reattaching it to the Magnaflow after-cat exha
15. Once the transmission crossember as cinched back onto the frame, the jack was settled allowing the tailshaft to rest on the new isolator mount before tightening it down. The final piece under the truck requiring reinstalled was the driveshaft.
15. Once the transmission crossember as cinched back onto the frame, the jack was settled
16. We lowered the hoist and topped off the Gearstar's fluids while the LS327 idled happily. Automatic transmission fluid has to be checked with the engine running and the fluid warm, to gain the correct reading on the dipstick.
16. We lowered the hoist and topped off the Gearstar's fluids while the LS327 idled happil

Gearstar 4L60e Transmission Hitting All The Gears Test

17. Before we headed out on the road, the truck was left slightly off the ground to allow the transmission to run through its gears a bit to ensure everything was as it should be.

17. Before we headed out on the road, the truck was left slightly off the ground to allow

From The Driver Seat
The Transmission House did a great job of handling the swap like the professionals they are, but keep in mind, this is an install you don’t have to be afraid to do in your own driveway. With all the right tools and equipment, the job went smooth as silk. Once out on the road, the slightly firmer shift was barely noticeable under light throttle conditions and it was a nice change to step on the throttle and have the truck move ahead with the authority we always thought it should have. Between the new engine and transmission, our truck should last another 150,000 miles with proper maintenance. One item we didn’t show being installed was the Hayden auxiliary cooler. Heat is the number one cause of failures in automatic transmissions, which is why Gearstar ships all of its units with a Hayden box of goodies. When you do your transmission swap, remember to flush all the lines and install an auxiliary cooler to protect your investment and extend its life.

Your Questions Answered
Degree of Difficulty:	Intermediate
Time Spent Working:	3 Hours
Tools Needed: 10mm, 13mm, and 15mm wrenches and sockets, a floor jack, pry bar, and safety stands.
Parts Used:
Gearstar Level Two 4L60E	$2,295.00
Total:	$2,295.00
(prices from the manufacturers do not include tax, shipping, or installation)

SOURCE
Gearstar Performance Transmissions 132 N. Howard St. Akron OH 44308 800-633-2353 www.gearstar.net	The Transmission House 569 N Citrus Ave Covina CA 91722 1-626-966-8515 http://www.transhouse.com