today i was driving and i felt a slip. so i figured i change the fluid nd filter. when i did i lost reverse, 3rd slips bad 4th slips and wont go into overdrive and tow haul flashes but doesnt bring a code up. anyone have any ideas? idk what happened

 

the first response to this is we need more info! How many miles on your truck? What mods have been done to your engine and trans? Do you tow with the truck? Are you running a programmer? How often has the trans been serviced if at all. When you felt the trans slipping, was it during acceleration or during a shift? If during a shift what gear to what gear? How did the filters and fluid look when you drained and replaced. If you dropped pan and changed filters did you overfill or under fill trans? The more info you give the easier it will be to help you diagnose the problem. Sorry to hear your having trouble. I go freakin nuts when my truck acts up, so i feel your pain right now.

 

You can't get the trans codes with a standard code reader typically. You'll need to have it scanned with something like Autoenginuity or IDS etc.

I had similar issues. Could be the snap ring, it's about the only common failure in a 5R110. Tough to say.

 

Just did MDubs tranny. Reverse pistons go in these. It seems to be common along with snap rings for the direct clutches ive seen that a ton of times. Mdubs trans-short of nuking a planetary set was one of the worst ive seen in a long time. The pump was replaced, direct clutches (would be your slips and not engaging overdrive) the reverse piston, and a whole lot more. Pretty much everything is new in his trans. Go take a line pressure reading when the trans is up to temp. Post the results.