Hey Scotty, I bought a new battery from autozone for my 07 avalon, and for the sake of convenience I had them put it in. The car has driven fine up until yesterday when I came to find out that the negative terminal was a little bit loose. I was getting on the freeway on ramp, and because it was uphill I had to step on the gas a decent amount, about 4000 RPMs. At probably 40mph, all my electronics suddenly flickered, shutting my screen, dash lights, and everything off and on again, and producing a loud thud that had me moving in my seat. After finding that the battery connection was loose I tightened it and continued on my marry way. It still runs fine and shifts fine, but I'm worried about the damage that may have caused. That was not a gentle thud. Do you think it caused damage? How would I check for damage, and would it be in places in addition to the transmission?
OK this is just a guess here but is your tranny electronically controlled?
Perhaps when you lost power for a second, the tranny actually jumped out of gear and then right back in.
I had that happen in a Ford van. Just a guess, I'm sure you'll get a better answer from some of the more knowledgeable guys here.
it's a 2007, so the transmission will 100% be electronically controlled (assuming it's an auto). Electronic shifting was introduced in the early 1990's.
Let me get this straight.
Did the person that installed your battery [ hopefully not you ] fail to secure it in the battery box?
If so I'd definately go back where I bought it and raise holy h*ll.
If that thud was the battery falling out, secure it.
Nope it wasn't me that installed it. And nope it wasn't the battery falling out, it was just a loose negative terminal. The power cut out because of a loose power connection. It was almost certainly a transmission thud in my amateur opinion.
It was probably a suddenly applied shift, but you'll never know.
If it still runs and shifts fine then I wouldn't worry about it.
