hello

mike17 · 03-09-2008, 05:47 PM

my names mike, i am 17 years old, and own a 1972 F-100 with a 302.
i bought it in august of 2006 from the original owner, in fact he even gave me the original sales receipt from the day he bought it. its got 205k miles on the original engine. i was given two extra transmissions, one of which is the original c-4 and the other a c-6. it had a c-5 from a 86 f150, i took it out this past weekend and put the c-6 in. it has been rebuilt, but im having trouble with it downshifting, it just stays in 3rd and im afraid of burnin up the engine

bkf77 · 03-10-2008, 07:01 AM

How long ago was the trans rebuilt? Just wondering if it has a warranty? Sounds to me that there is a possible valve body problem. Maybe a check ball or something was placed in the wrong spot or a spring in worn.

mike17 · 03-10-2008, 08:41 AM

im not really sure when it was rebuilt but i do know that its been at least 15 years, i was thinking that it just needed to get used and broken in. also i was going to adjust the bands and the kick-down

jonmark1985 · 03-10-2008, 09:16 AM

leave the bands alone, just adjust the kick down, it may not even be hooked up. I doubt you'll burn the transmission up without using the kickdown, you just won't have a very good passing gear unless you manually shift the truck into second gear.

bkf77 · 03-10-2008, 09:59 AM

Next question, why did you change the trans? Was the old one not working as well? If the trans had been sitting for 15+ yrs, I would suspect sticking valve body parts or broken springs.

mike17 · 03-10-2008, 11:32 AM

i changed the transmissions out because the last one was constantly slipping from first to second, the only way to get it to downshift is to either manually shift it or stop, go to reverse, then back to drive. all the other gears shift fine

bkf77 · 03-10-2008, 12:15 PM

What does the fluid in C6 look like? Dark or miscolored? I'm thinking valve body components due to sitting for some time without use.

mike17 · 03-10-2008, 01:45 PM

i took the pan off before install to check it but it was fine, there was a fresh filter already on it. i got another filter and new gasket and changed it anyway. after the install i put fresh fluid in and let it run for a bit then drove down the street. it shifted through 1st, 2nd, and 3rd then wouldnt come out of 3rd. im so lost with transmissions any advice is helpful. thanks

bkf77 · 03-10-2008, 01:47 PM

I stilll think valve body problem. Could also have internal seals that dried up while it sat.

mike17 · 03-10-2008, 01:57 PM

im guessing that the transmission would have to come out for that huh