GM 6L80/90: Cracked or Split Sump Filter

From a recent Automatic Transmission Service Group (ATSG) Online Technical Bulletin:When the GM 6L80/90 transmission presents with a complaint of no forward or reverse movement, or slipping badly in all ranges, initial inspection may reveal a cracked or split sump filter (see Figure 1). However, filter quality may not be the underlying issue.Damage to the pump itself can be found upon disassembly of the transmission (see Figure 2). This damage can cause high pressure spikes, which can force fluid into the filter neck and cause the filter to split or crack. When the filter is found in this condition, always check for pump damage as well as other possible internal distress.To correct this issue, ATSG recommends repair or replacement of the damaged pump parts, or replacement of the pump assembly, along with installation of a new, high-quality sump filter. FIGURE 1 (Copyright © 2015 ATSG)Split Sump Filter FIGURE 2 (Copyright © 2015 ATSG)Filter Neck DamageInformation and images provided with ATSG's permission.