4L80E Swap Transmission Crossmember for 2WD Silverado

When you pull the 4L60E out of a 2WD GMT800 or GMT900 truck and put a 4L80E in its place, the factory crossmember no longer lines up. The 4L80E is roughly four inches longer and its mount pad sits further back, so the stock member either will not bolt to the tailhousing at all or forces the driveline into a bind. This crossmember is built to that longer case dimension and bolts to the frame in the factory holes, so the swap does not turn into a fabrication job.

Fitment is 2000-2013 Chevrolet Silverado 2WD and 2000-2013 GMC Sierra 2WD. It is intended for trucks being converted from a 4L60E to a 4L80E, not for chassis that already came with a 4L80E from the factory. Construction is mild steel with a powder-coated finish, 30.71 x 10.83 x 4.53 inches, 9.53 pounds, ECOTRIC part number VC-LYAM-499-2.

On the bench side of the job, the crossmember also opens up clearance where the exhaust runs past the tailshaft. That is the spot most swappers end up fighting, because the 4L80E pan and case push the pipe outward and the stock member leaves no room to route around it. Support the transmission on a jack, drop the old crossmember, set this one in, snug the frame bolts, then torque the mount last so the transmission sits at its natural angle before anything is drawn tight.

No instruction sheet ships with the part, and it assumes you already have the 4L80E swap hardware sorted out (driveshaft length, TCM or controller, and the wiring). If you are quoting the job, budget the driveshaft shortening at the same time you order this, since the shorter driveshaft is the other hard requirement of the conversion.