I took my car to the dealership because it backfires after 20mph. The dealership says I need a new transmission. Do you agree with them?
The transmission was possibly putting some sort of increased load on the engine. You may want to have the fault codes read out of the engine and transmission. Volkswagen has a TSB out for an improper shift from 2-3 gear, which would be near the 20 MPH range. There is an updated software for the transmission to correct this, if this is the problem. However, the software level would need to be updated using the Volkswagen VAS system. You may want to enlist the help of an certified mechanic to inspect your gear slipping issue first before spending money on a transmission overhaul or replacement unit.
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