1991 Pace Arrow owners.......Question

I have no button for engageing the overdrive on this rig. I will have to check to see exactly what model transmission I have on this rig. It is a 454 TBI. Letters on shifter read as follows 1 - 2 - D and then D with a square around the D. I was assuming this was an overdrive transmission.
I will check the model number on the trans, but in the mean time, anyone know what I may have here?? thanks

posibly a 91 on an earlier chasis. The 91 chasis was the first year with the 480LE trans.

If you have the 454 TBI eng and the 4080LE transmission 2500 rpm at 65 is about normal. 3000 at 60 mph sounds high for a 4 speed transmission I don't have an overdrive light on the dash. Are you sure it is a 480LE trans? If it is a 3 speed then the rpms make sense.

I had a 91, let me see now. If I remember correctly, when you push the button on the shift lever, the od light comes on, but overdrive is locked out. 3000 thousnad and 55 sounds a little high