I needs help!

Driving to work this morning then again at lunch the oddest thing happened. My truck wont shift into it's final gear until I hit 65 and about 2200 rpm and let off the gas. It's been running fine, then all of a sudden this happens. Any ideas?

 

Is the truck warmed up? My truck shifts higher when its cold out and its not up to opperating temp yet.

 

Has it done it since then? Did you check your fluid?

 

Plenty warm.

Haven't checked the fluid yet. Will be doing that before I leave after work.

 

Fluid level is fine. It happened again this morning. I'm confuzzled.