Cant recall what kind of GM automatic transmission my 2001 Saturn LW300 uses, but it has no dipstick. The transmission is serviced normally; you just add the fluid through a threaded on fill cap. The amount you pour in is indicated in service literature. Nothin compares with the lack of OIL dipsticks, I think the dependence on electronic oil level readouts is a BIG mistake; they are not 100% reliable or accurate.