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Bad batteries kill transmission!?

2448 Views 10 Replies 4 Participants Last post by  skinnyvito
So I took my truck to a highly recommended shop in my area because my lights were flickering.I checked my connections, batteries and alternator were less than a year old so I thought a pro could figure it out fast. He did,bad batteries( crappy tire) but on a test drive he lost 2 gears in the transmission! I just bought a NADP Heavy Hauler this summer WTF! NAPC says I had a electrical problem first, it's an electronic trans.... I didn't drive long with the problem, trans light never showed up while I was driving, and I haven't drove at the hp I told NADP I was shooting for. NAPC is talking to the mechanic about it, I hope there gonna warrantee it, i did not wanna buy myself a trans for Christmas. So if in doubt don't b cheap buy 2 new quality batteries.
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Happened to the mechanic on his test drive, when I drove there seemed like it shifted down from 6-5 easier than usual, but I drive 3 different trucks so I could b wrong. I'll b talking to mechanic more today. Get more details.
Shifts 1-4 fine no 5 or 6 it just won't shift up after 4, gear ratio code. I didn't get a specific number, mechanic is confident it is a warrantee issue. I'm waiting to hear back from NAPC...
Thx TransEngineer hope that means good news when the bill comes in, trans seemed great until now told them I was shooting for 650 hp, they were very confident the package they gave me could handle more than that. I don't know the specifics of their upgrades offhand, paperwork is with truck. last dyno was little over 450, I did some upgrades since but haven't run high tunes because I want to tune on dyno to stay within my goals and try to eliminate all smoke possible. Glad it didn't happen hauling family thru the mountains, I'm sure NAPC will take care of it and I won't have any more problems. Still waiting to hear from them...
Lol, could b. I enjoy it. He was very well recommended by multiple people, I try to do all my own work unless it causes warrantee issues (trans was pro installed) so when I have to get work done I go to a trusted dealership or well known shop.I'm quite embarrassed my issue was batteries and I couldn't resolve it myself, I don't have aftermarket stereo/starter or other electronics,batteries were new... Should know better by now not to get cheap parts, even if I gotta wait/travel for quality ones.
New trans coming, thx NAPC! There's so much info on this site referring to electrical issues, some bypass ECM/TCM when they find a problematic wire, some find a problem in the ignition, it seems to go on. Hope the batteries were the only thing wrong, other than the trans. Hope to have it back for the next sled trip I h8 putting my nice sled on a Chevy then ducking all the way to mountains in case someone sees me!!
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