Helloooo out there... I just had a trnny fluid "flush" done at Jiffy Lube. They say that the back flush is supposed to clear the filter of debris. The PROBLEM: is that shortly after the flush n fill the tranny won't shift from 2nd to 3rd or above. I talked with a couple of mechanic friends who suggested a complete filter and fluid change. I have a '98 f150 4x4, don't know the tranny model #, and I shudder at the thought of a rebuild ($$$$). From take off and shifting into 2nd it's as smooth as a silk, bu tjust won't continue. In fact it slips completely in OD. Reverse is no problem either. Thoughts? Ideas?

 

A buddy of mine had the same problem. He went to one of those fly by suck shops and had exactly what you had done. He ended up removing a plugged trans filter. I hope this helps.

 

A simple tranny flush would not do this. Were there any symptoms before hand? It sounds like you lost the dirrect clutch that holds 3/4 gear. Common to wear out when pulling, but not just out of the blue one day.......

 

Mine's in the shop now same prob.
will let ya know what we find

 

A blocked filter typically would cause horrible shifting all over, not just into specific gears. One problem with the trans flush machines is that they can strip out the clutch material from the fluid in high mileage trannys that haven't been regularly maintained. If a tranny has never been serviced and has buuko miles on it, the trans fluid that's sludged into the clutch packs will actually hold the clutch material in place and allow the clutch to still hold. Once you hook up one of the pressure type trans flush machines, it can actually push that mushy clutch material right out of the clutch packs and cause those clutches to stop working.

I've only seen it happen twice on some very high mileage trannys. It's typically not an issue on any trans thats been maintained. Just a thought in case your tranny was one of the high miler units....