Tranny slip?

[WhySsoSseriouss]

So this morning we were leaving the house to take my wife to work and as i was reversing we heard and felt a sudden thump and the truck would not reverse it just would rev up. I put it back in park and turned it off, turned it back on a moment later and put it in reverse again, it began to reverse fine then the thump again but this time it continued to reverse.

I took my wife to work and once there i checked the transmission fluid. It was in the HOT range but below the add so i figured i would get some and add it. When leaving her work it did the thump again but continued to back up. Once at advanced and after getting a LUCAS transmission cleaning solution i headed home, it did it again when leaving there. I went to check the fluid once home and it is completely full.

So any ideas on what i should do next?

 

[DarrinBC]

Hate to say it, but that doesn't sound good. If the fluid is full then the least it could be in in the valve body. But with the "thump", it's most likely the reverse clutch,.

D