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Bad batteries kill transmission!?

2447 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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4th gear - limp mode

A few years ago I had a similar problem.

In the winter months, when the engine was cold, my transmission would sometimes go into limp mode and not leave 4th gear. If I shut it off and restarted it, it would be okay. This is a stock truck.

I took it to the dealer and they said it was a bare wire causing this. (It didn't fix anything.)

I put in new Deka batteries. It didn't happen again until last month. I have been cleaning the grounds every place I can and hope to fix this problem.

I don't remember the code this caused.
new trans

I'm glad to hear it's working out for you.
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