Nine-piece driver set that presses every bushing in a GM 6L80 or 6L90 case squarely, without scoring the bore or cocking the bushing.
This nine-piece set is for the rebuilder or serious home builder who has a GM 6L80 or 6L90 torn down and wants every new bushing to go in straight the first time. It covers the six-speed used from 2006 on in 2WD, 4WD, AWD and RWD Chevrolet Silverado, Tahoe and Suburban, GMC Sierra and Yukon, Cadillac Escalade, Camaro and Corvette. Seven solid steel mandrels and two driver handles, heat treated and black oxide finished, built to replace the 104BDMK set. The common search behind it is a 6L80 that keeps coming back with shudder, low pressure or burnt clutches even after the obvious parts were changed.
In the 6L80, fluid for the clutches travels through the stator support and through the shafts and drums that spin inside it, sealed by rings that ride in tight bores. The bushings hold those shafts on center. When a bushing wears, the shaft can move off center, the seal rings stop sealing evenly, and the circuit they feed loses pressure. Sonnax puts it plainly: OE bushing wear in these units lets fluid escape and throws parts out of alignment, leading to harsh shifts and clutch failure. A mandrel from this set registers on the bore and pushes on the face of the bushing only, so it enters square and stops at its seat. Because the mandrels are hardened, the shoulder keeps its edge under press load rather than flattening over after a few jobs.
Do not assume bushings until pressure and controls are ruled in or out. Start with mainline pressure compared to commanded pressure, the test Gears Magazine describes for the 6L80, and with a valve body that passes a vacuum test. If the hydraulic controls check out and the unit still loses pressure in one range, the leak is usually in the rotating circuits, where bushings and seal rings live. Our 6L80 common problems and fixes guide lays out the failure patterns, and the 6L80 Corvette shift problems guide shows the adapt and pressure checks to run before tearing a unit down. On the bench, measure clearance at every journal against your rebuild manual.
The listing covers the GM 6L80 and 6L90 six-speed automatic, 2006 and up, in every drive layout. The bushings sit in the same places regardless of 2WD or 4WD, so the same set works on a truck, SUV or car unit. It does not fit the smaller 6L45 and 6L50, which use a different bushing kit, or the front-drive 6T series. The set is tools only, and bushings are sold separately. Confirm your unit by its RPO code (MYC for 6L80, MYD for 6L90) or send us the year and VIN, and browse matching parts on our 6L80 transmission parts page.
Set the housing on a machined face, never on a gasket surface or a thin web, so it stays flat under load. Use a shop press for every bushing you can reach that way; Sonnax specifies an arbor press for precision bushings because hammering can distort them. Where a housing will not sit square in the press, use a handle with a dead blow and keep the strokes light. Record each old bushing's depth and oil-hole position before you remove it, clean the bore, lube the new bushing with Dexron VI, and press until the mandrel bottoms. Then bore-gauge it and spin the mating shaft by hand. This set pairs with a complete kit like the 6L80 master rebuild kit with steels, frictions and filter, and refill with full synthetic Dexron VI ATF before the relearn.
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No. You get seven mandrels and two driver handles. Buy the bushings for your 6L80 or 6L90 separately or use the ones in your rebuild kit.
Yes. It is listed for 2WD, 4WD, AWD and RWD 6L80 and 6L90 units from 2006 on. The bushing locations do not change with drive type.
They can. Sonnax lists TCC apply and release concerns and code P0741 among bushing wear symptoms, because a worn bushing can let the converter clutch feed leak.
Sonnax recommends an arbor press for precision bushings because it gives you feel and steady force. Support the housing on a machined face and press slowly.
Bore-gauge each one, confirm the shaft turns freely, finish the rebuild, fill with Dexron VI and run the transmission adapt relearn with a scan tool.
