[deanp]

The Tahoe got the 6L80 in 2009. 250K out of a 6L80 is good. I just had mine rebuilt at 143k and the shop I used said they have been rebuilding 3-8 per week for the last two years (look for separate thread). Aftermarket suppliers like Sonnax have stepped up and have found the shortcomings of the trans design and are offering parts that improve durability.

Full rebuild was $4200, so $6k with dealer labor costs and dealer mark up is high, but probably not out of whack. Labor was 8.6hrs @ $108 for remove/replace flush cooler, update thermo coupler reset and relearn computer. Labor for the rebuild itself was 8.3hrs @$108. Parts were $2251. Keep in mind labor for remove/replace is on a 4WD.