As we marched into the era of electronically controlled transmissions, the debate was no different in the olden days when trying to decide between a Turbo 350 and Turbo 400. The TH350 is lighter and doesn’t eat up as much power. Meanwhile, the TH400 is nearly bulletproof and has better gear ratios for higher-powered cars. History repeats itself when it comes to the four-speed 4L60E and 4L80E, except the gear ratio difference is even more dramatic. While the 4L80E uses a 2.48 First and 1.48 Second gear just like the TH400, the 4L60E has a 3.06 First and 1.63 Second, which was a holdover from the 700-R4 and better suited to a dump truck or the anemic 305s of the era. With a modern LS engine, you have massive torque multiplication in First gear, and then it falls on its face in Second. This is not a good combination, particularly when you add in sticky tires and a happy front end at the dragstrip. Thankfully, PerformaBuilt offers more performance-friendly ratios on its Level 3 Black Edition 4L60E that bridges the gap between your typical performance rebuild and the power-sucking 4L80E.
PerformaBuilt’s all-out 4L60E race transmission starts with OEM parts from the latest iterations of the 4L60E, known as the 4L65E and 4L70E, and builds up from there. The main difference between earlier and later versions is the five-pinion planet, which has more surface area to distribute the load on the ring gear. However, in switching to a 2.84 First and 1.55 Second gear, PerformaBuilt uses a Sonnax six-pinion planet on the input carrier that has even greater durability. By also adding billet shafts, special carbon surface clutches, and a Sonnax Smart Tech Drum, this transmission will hold over 1,000 horsepower in most Chevy cars. Some of the other stout features include a billet Second gear servo and dual-piston overdrive servo to hold each gear under wide-open throttle. A 13-vane pump with hardened rings is set to a max of 220 psi. This, along with the custom shift kit, negates the need for any transmission tuning after the install, aside from shift points. Perhaps the best part is that PerformaBuilt dynos each transmission before it leaves the shop and backs it with a one-year warranty. Challenge accepted.
With such a stout transmission option, many Chevy owners will no longer have to worry about shoehorning in that power-robbing 4L80E or resigning to use a three-speed. PerformaBuilt’s Level 3 Black Edition 4L60E is a plug-and-play alternative for your LSX engine and PCM that can even take commands from some aftermarket computers. In fact, some fifth-gen Camaro guys have been swapping out the less-aftermarket friendly six-speed 6L80E for the 4L60E, using either an OEM or aftermarket controller. Bigger and more isn’t always better. Sometimes it just takes the right combination of parts to go faster and have more fun on the street.
Follow along for a look at what makes this transmission so capable.
01. The Level 3 Black Edition upgrades the majority of the components from the factory 4L60E. Even the OEM case is heat-treated and painted with a durable black enamel. The difference between the Black Edition and the regular Level 3 Invincible series includes billet shafts, special carbon surface clutches, and a Sonnax Smart Tech Drum. And of course, on this version it also has a six-pinion planetary with 2.84/1.55 ratio First and Second gears. It is worth noting that PerformaBuilt’s 700-R4 is very similar to this minus the electronics. And PerformaBuilt also rebuilds the 4L80E, TH400, TH350, 200-4R, and other transmissions.
02. The Sonnax 2.84 Ratio Input Carrier (six-pinion planet) is the impetus for changing the gear ratios. It effectively reduces the gap between First and Second gear, and the subsequent drop in rpm after the gear change. This converts the 4L60E to a close-ratio four-speed. The added pinion is a nice side benefit, as are the PTFE-coated thrust washers and thicker captured bearing.
03. Here is a look at the six-pinion planet (left) next to the 4L65E and 4L70E’s five-pinion (center) and the 4L60E’s four-pinion (right).
04. Just going from the OEM four-pinion rear planet (right) to the five-pinion planetary (left) is a huge upgrade in strength by spreading the load over a larger surface on the ring gear.
05. The BorgWarner 29-element dual-cage sprag assembly is the strongest available and standard in all Level 3 transmissions.
06. The Sonnax Smart Tech Drum assembly is complemented by a billet input shaft and carbon frictions. The billet bolt-on plate eliminates the possibility of blowing out the lugs and snap ring used in OEM transmissions.
07. The Black Edition uses Sonnax billet servos, which increase the holding power of the band in Second and Fourth gear. Some builders overlook Fourth since you won’t typically be at WOT unless you’re doing some top speed racing. However, it is good insurance should you lose Third or need to pass someone on the highway.
08. A new reverse-input drum is paired with a carbon band that is 40-percent wider with stronger lugs to further increase the holding power of Second and Fourth. A new drum gives an ideal mating surface that is perfectly flat for the band to grip.
09. Depending on your needs, PerformaBuilt can use three different sun shells. OEM is to the right, the Beast in the middle, and the Sonnax Smart Shell on the left. The latter is being used in this Black Edition. The thickness and the hardened tabs on the Smart Shell are what separate it even from the Beast.
10. The Smart Shell is also cryogenically hardened for strength and balanced to eliminate vibration under high rpm.
11. The output shaft is another critical upgrade to the Black Edition. The Sonnax billet version is much beefier than stock.
12. It is important to specify which application and electronics you are using. The version on the right is for the later 4L70E, which has a long, thin white plug (top right) for the input speed sensor. The short black wire sitting next to it is the input speed sensor that bolts to the pump.
13. Installation begins with a cleaned, heat-treated, and painted case. The heating process helps the paint adhere for a more durable finish.
14. The Invincible and Black Edition use the five-pinion set with high-performance low reverse clutches.
15. Next comes the heavy-duty OEM low roller assembly …
16. … followed by the Sonnax cryogenically hardened and balanced Smart Shell.
17. The Sonnax 2.84 Ratio Input Carrier (six-pinion planet) sits inside and splines into the ring gear.
18. PerformaBuilt then starts on building the Sonnax Smart Tech Drum with carbon clutches.
19. Now it is on to the BorgWarner 29-element dual cage input sprag assembly.
20. PerformaBuilt achieves a 0.0020-inch clearance with its steels to generate a crisp shift that works with the valvebody to be progressive and not violent. This prevents transmission damage and a jarring ride.
21. At last, the 3-4 clutch and steel set is complete.
22. The input shaft (with new Teflon seals) and reverse-input drum is then fitted on to the input drum.
23. The entire assembly is dropped into the case next.
24. The modified valvebody is installed below, along with its wiring, then capped off with a Corvette filter and extra-deep chrome pan. Slots are cut to enhance fluid flow through the filter, and a long neck is needed to support the filter in the deep pan.
25. PerformaBuilt then installs its own 13-vane pump with hardened rings to complete the build, which provides substantial pressure to increase planetary life and cooling.