The '02 Tahoe is acting up.
Today, I got in, started it, put it in reverse to back out, no movement...
Put it in Drive, moved a tad forward, put it in reverse, backed up fine.
Turned it off, started it, put in reverse, worked fine.

any ideas of what I should be checking? the fluid looks fine.

it has 44k miles on it, and I am planning on a transmission service (fluid/filter).
anything else?

TIA.

Jim (transmission clueless...)