Cactusbat
Newbie
My roommate and myself have searched forums (this one and others) for hours and can't find my particular issue and I'm hoping one of you transmission wizards could answer this for me. I'll give you a brief rundown of the situation before the question.
My transmission died a week ago after being (half-assed) rebuilt in March. Suffice to say I got screwed, and come this time around I didn't have the money to turn it over to another shop, and my roommate and I opted to rebuild it ourselves. My roommate is a mechanic but doesn't do a lot of transmission rebuilding and I mechanic mostly on heavy machinery and as a hobby. Anyways, we nitpicked through it, corrected the problems the previous rebuilder caused, replaced as many hard parts as I could afford and needed (pump, reinforced sun shell, and overhaul kit mainly), and till I took it out for a test drive, we saw no issues. It shifts beauuuuutifully to Reverse, 1 to 2, 2 to 3, but from 3rd there's nothing. All downshifts are smooth as butter too. Roomies Modus reports the computer is commanding a 4th gear shift but there's absolutely no mechanical response or attempt to shift. No noise, no nothing. TCC lock is occurring while cruising in 3rd but the truck just rides in 3rd as if 4th doesn't exist. We've double checked what we can without dropping the pan such as the servo piston orientation, O ring condition, electrical plug pins, and can only come up with one possible cause.
TL;DR My question is this; if the 3-4 relay in the valve body were accidentally put in backwards, would that cause the shift to 4th to just never happen? Is there another part that could be causing this that we're not considering?
Thanks in advance!
My transmission died a week ago after being (half-assed) rebuilt in March. Suffice to say I got screwed, and come this time around I didn't have the money to turn it over to another shop, and my roommate and I opted to rebuild it ourselves. My roommate is a mechanic but doesn't do a lot of transmission rebuilding and I mechanic mostly on heavy machinery and as a hobby. Anyways, we nitpicked through it, corrected the problems the previous rebuilder caused, replaced as many hard parts as I could afford and needed (pump, reinforced sun shell, and overhaul kit mainly), and till I took it out for a test drive, we saw no issues. It shifts beauuuuutifully to Reverse, 1 to 2, 2 to 3, but from 3rd there's nothing. All downshifts are smooth as butter too. Roomies Modus reports the computer is commanding a 4th gear shift but there's absolutely no mechanical response or attempt to shift. No noise, no nothing. TCC lock is occurring while cruising in 3rd but the truck just rides in 3rd as if 4th doesn't exist. We've double checked what we can without dropping the pan such as the servo piston orientation, O ring condition, electrical plug pins, and can only come up with one possible cause.
TL;DR My question is this; if the 3-4 relay in the valve body were accidentally put in backwards, would that cause the shift to 4th to just never happen? Is there another part that could be causing this that we're not considering?
Thanks in advance!
