4L80E Planetary 2001, used and ready to install. Fits the 4L80E. Ships fast from the USA.
Shopping for a 4L80E overdrive section for a 2001 or later Silverado or Sierra 2500 or 3500, Suburban 2500, or Express or Savana van? This listing is a used 2001-and-up overdrive planet kit: the overdrive planet, the sun gear, the overrun drum with the later blue sprag type one-way clutch, and the shaft. The drum was taken apart and checked for play, the clutches and steels inside were inspected and judged to be in good used shape, and the planet teeth were checked for chips. It is the part to reach for when a late 4L80E has lost D, picked up a speed-related whine, or dumped overdrive debris into the pan.
Every 4L80E stacks a simple overdrive gearset ahead of its three-speed main geartrain. Torque from the converter turbine comes in on the shaft and drives the overdrive carrier. During first, second and third gear, the sprag (a one-way roller clutch) inside the overrun drum ties the overdrive sun gear to the carrier, so the whole front section turns at input speed. For fourth, the fourth clutch grounds the sun gear, the sprag overruns, and the pinions walk around the stationary sun to spin the ring gear faster than the input. The overrun clutch in the same drum is applied only in the manual ranges, which is how the 4L80E gets engine braking.
Sonnax TASC Force specialist Jim Dial, writing in Transmission Digest, points out that in the overdrive range the roller clutch carries the load by itself, and that in plow and towing trucks overheating can melt its plastic cage and kill it quickly. Late trucks with the 6.0L and 8.1L engines tow plenty, so the same failure still shows up.
Compare drive in D against manual 2 and 1. If only D is gone, the sprag is the prime suspect. Scan for codes too. A ratio code can come from a weak speed sensor signal, and the 2001-up trucks share the electronic shift and pressure control faults covered in our 4L80E Silverado 2500 shift problems guide. Low line pressure from a failing pressure control solenoid can also cause slip in every gear; see the 4L80E EPC solenoid symptoms guide before tearing the unit down.
This is the 2001-and-up blue sprag overdrive assembly for the 4L80E, the later design that differs from the black sprag parts used in 1991-2000 units. It is meant for 4L80E transmissions built in 2001 and later in GM heavy-duty pickups, Suburban 2500 and full-size vans. If your unit is a 1991-2000 build, order the 1991-2000 black sprag overdrive kit or convert with the complete update kit. Do not mix a late drum with an early planet or sprag; install the assembly as one matched set. Transmissions get swapped, so read the ID tag on the case, or send us your year and VIN and we will confirm before it ships. More hard parts are on the 4L80E collection page.
| Fits | 4L80E 2001 |
| Part type | Planetary |
| Condition | Used |
| Brand | OEM |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Not as a direct swap. This is the 2001-and-up blue sprag design. Early 1991-2000 units use the black sprag parts, so choose the 1991-2000 kit or a full update kit for those.
The overdrive planet, sun gear, overrun drum with the blue sprag type one-way clutch, and the shaft. The drum was disassembled and its clutches and steels were checked.
That pattern points to the overdrive sprag, which holds alone in D. Confirm with a pan inspection and a code scan, then replace the overdrive section as a set.
Install the drum, sprag and planet together as delivered. Mixing early and late overdrive parts can cause fit and holding problems.
Dexron VI. GM's 2008 Express owner manual lists 7.7 quarts (7.3 L) for the 4L80-E. After a rebuild, fill gradually and check the level hot rather than going by a number alone.
