transmission slipping

[wdavenport@sc.rr.com]

transmission just started slipping on my chevy z71 4x4.I have a 5.3 engine,not sure what trans.crank up truck runs fine then when it gets up to tempthe transmission starts slipping then it just acts like its in neutral.started all of a sudden.any advice.

 

[zora]

Did you check the transmission fluid level? Do you know how many miles since the transmission fluid and filter were changed?