Nine-piece hardened steel driver set that installs GM 6L80 and 6L90 pump, stator and drum bushings square in the bore without scoring them.
If you have a GM 6L80 or 6L90 torn down on the bench and a new bushing kit in a bag next to it, the last thing you want is to ruin a pump body or center support by driving a bushing in with whatever socket happens to fit. This nine-piece set gives you seven stepped steel drivers and two handles sized for the bushings in GM's rear-drive six-speed, the unit behind the 5.3, 6.0 and 6.2 in Silverado, Sierra, Tahoe, Suburban, Yukon and Escalade, plus Camaro, Corvette, CTS and the Hummer H2 and H3 from 2006 on. It is listed as a replacement for tool numbers 104BDMK and 6L80-Tool.
The 6L80 carries most of its rotating parts on plain bushings, and there are a lot of them. The Sonnax 6L80/6L90 bushing kit lists the pump bushing, two stator support bushings, front and rear 2-6/3-5-R hub bushings, the 1-2-3-4/3-5-R drum bushing, the case bushing, the 4-5-6 drum bushing, front and rear center support bushings and the output shaft bushing. Sizes run from the pump bushing, which rides a 1.834 inch converter hub, down to the 4-5-6 drum bushing on a 0.685 inch journal. Each driver in this set is stepped: a pilot that slips inside the new bushing and a shoulder that pushes evenly on its face. That keeps the bushing on the bore centerline as it goes in, which matters because several of these bushings also meter or seal clutch feed and lube oil, not just support a shaft.
Low or unstable line pressure on a 6L80 has several possible sources, so test before tearing down. Compare actual pressure at the test port against the commanded pressure on a scan tool; the 6L80 pump failure symptoms guide walks through separating a weak pump from a leak further down the circuit, and 6L80 common problems and fixes covers the valve body and TEHCM faults that mimic bushing wear. Once the unit is apart, measure each journal with a micrometer and each bushing with a bore gauge, and look for bushings that have spun or moved from their factory depth.
The set is listed for GM 6L80 and 6L90 six-speed automatics, 2006 and up, in Chevrolet, GMC, Cadillac and Hummer applications. The main case bushings are shared between truck, SUV and car versions, so one set covers them. It is not listed for the smaller 6L45 or 6L50, which use some different bushing sizes. No bushings are included. Confirm your unit by the RPO on the build sticker (MYC is the 6L80, MYD the 6L90), or send us your year and VIN. Everything else we stock for this transmission is on the 6L80 parts page.
Note the depth and oil-hole position of each old bushing before you remove it, then cut or collapse it out rather than hammering it through the bore. Clean the bore and lightly oil the new bushing. Sonnax warns that driving precision bushings with a driver and hammer can distort them and recommends an arbor press, so the best use of these drivers is as press mandrels: support the housing flat, pick the driver whose pilot fits the bushing ID with no slop, and press until the bushing reaches its original depth. Where a press truly cannot reach, use light, even taps. Afterward, check the fit on the mating shaft and spin it by hand. Pair the set with the bushings and seals in a 6L80E master rebuild kit with filter, use the input shaft seal ring expander tool for the sealing rings, fill with Dexron VI and reset the transmission adapts when you are done.
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No. It is seven drivers and two handles only. Use the bushings supplied in your rebuild kit or a dedicated 6L80/6L90 bushing kit.
It is listed for the 6L80 and 6L90. The 6L45 and 6L50 share some bushings but not all, so compare each driver pilot against the bushing before using it on those units.
Use an arbor press wherever you can. Sonnax cautions that hammer shock can distort precision bushings. These stepped drivers work as press mandrels, which gives you the alignment of the driver with the gentle load of a press.
On a full rebuild most shops replace them all. The pump bushing is the common wear point because it rides the converter hub, and worn hub and drum bushings are linked to P0741, harsh shifts and clutch failure.
Refill with Dexron VI using the check procedure for your vehicle, since many have no dipstick, then reset transmission adapts with a scan tool and complete a relearn drive.
