Hey folks, ok, got a 71 F250, 360 engine with the C6 tranny. A while, maybe 2 years ago, I removed the engine to clean it up, replace the freeze plugs and paint it. I removed the tranny to get to the rear freeze plugs also. I put it all back together, had a little trouble with getting the torque converter to clock? to the right spot, but eventually, it went back together. I have not driven the truck on the road yet, still need to do a few things, but since then, while in drive and reverse, the tranny will engage then disengage. I have tinkered with the selection lever at the tranny, need to find a better polyurethane piece. I have also replaced the modulator with a black ring one. Still, no effect. I had a member on Fortification say it might be the clutches may have issues from sitting but to just work the tranny and they should eventually start working correctly. I tried to do that, run it up and down the street but, since I did not have a radiator fan, did not want to keep truck running too long, I have since resolved that issue. So should I still try and drive the issue of out or could there be something else? I have new tranny filter, fluid and the cooling lines are new, I made with brake line, so all that is good.

thoughts welcome.

 

Can you expand on this a little? I'm not a transmission expert, but I do know that if you didn't get the TC to engage properly you could have damaged the front pump.

After that, who knows what could happen....

 

Low trans fluid can do this. So can a problem with the filter in the pan. It is also possibly old, hardened seals in the clutches.

 

Jim_K when I put the engine and tranny back together, they would be about 1/4" apart, I moved them away and took the torque conv off, then back on to where it slipped in a little further. wiggled it all back together. Mind you, I have never delt with automatic tyranny's till this point, always manuals so this was all new to me. Once I got it back in the truck and everything connected, the old starter would not turn the engine over, it did before all this. I got a high torque starter and that works. Maybe I did mess something up. Like stated before all this, everything was running like a top.

 

Sounds ok to me, so I would defer to Mark Kovalsky's response, as he has practical experience working on these. Me, I just break 'em!

But seriously, if the engine runs, and you don't hear any odd noises, run it up to temp (perhaps on jackstands so it doesn't leave you stranded somewhere) and check that the level is good.

After that, I got nuthin'.

Good luck!