I'm having some issues with my 3-2 downshift in my 03 lb7 duramax. I rebuilt the trans with Evans kit and a suncoast 1057 converter.
I've put around 7k miles on it, all of my up- shifts are perfect (except the full throttle 3-4 has a slight double shift) but I'm having some issues with the 3-2 downshift. Sometimes it's perfect and downshifts just like it's supposed to, but about half the time it make a clicking noise and it usually not rough but every once in a while it's pretty violent. I have also noticed if I come to a hard stop from 5th gear the 5-4 downshift can be a little rough but not nearly as often.
I have changed the spin on filter and fluid (which looked great after 5k miles), tried another 03 tcm, made sure I didn't have any other codes and changed the pressure switch in the trans but still can't figure out why it's doing this. I do have a tech2 and did a fast learn when I changed tcms but it's still doing it.
Due to the frequency of it happening I can't imagine it being something internally in the trans except for it being something hanging up in the valve body. When I'm in tow/haul mode, it doesn't ever do it and downshifts exactly like it's supposed to everytime.
Does anyone have any ideas on what I can verify in the valve body? Normally I wouldn't worry about it but it does get annoying to have an unexpected rough downshift sometimes.
Thanks
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I've put around 7k miles on it, all of my up- shifts are perfect (except the full throttle 3-4 has a slight double shift) but I'm having some issues with the 3-2 downshift. Sometimes it's perfect and downshifts just like it's supposed to, but about half the time it make a clicking noise and it usually not rough but every once in a while it's pretty violent. I have also noticed if I come to a hard stop from 5th gear the 5-4 downshift can be a little rough but not nearly as often.
I have changed the spin on filter and fluid (which looked great after 5k miles), tried another 03 tcm, made sure I didn't have any other codes and changed the pressure switch in the trans but still can't figure out why it's doing this. I do have a tech2 and did a fast learn when I changed tcms but it's still doing it.
Due to the frequency of it happening I can't imagine it being something internally in the trans except for it being something hanging up in the valve body. When I'm in tow/haul mode, it doesn't ever do it and downshifts exactly like it's supposed to everytime.
Does anyone have any ideas on what I can verify in the valve body? Normally I wouldn't worry about it but it does get annoying to have an unexpected rough downshift sometimes.
Thanks
Sent from my SM-N920R4 using Tapatalk
