I brought my 07 automatic V6 Mustang to my dealer to get it's 30,000 mile tune about a week or two ago. When I got the car back I noticed the car was shifting funny especially from park into drive. It didn't feel like it was catching until I stepped on the gas a bit and while in drive it would slip into what seemed to be neutral. My car never had any issues like this ever so I called my dealer and they told me to bring the car back.

The mechanic told me that occasionally a bubble gets into the line and causes the problem. He rechecked the transmission fluid and then put the car down and couldn't get it to shift at all. I was freaking out despite knowing that I still have 2 years warranty coverage on my transmission. He asked if I could wait so he could double check his work when the car cooled off and I did. Then he came out and told me that he found the problem, the transmission filter was bent and was not forming a correct seal and he must have not noticed it when he installed it during the 30K tuneup and it must have been bent straight out of the box. First time he had ever seen this in 40 years of being a mechanic. (He actually showed me the filter and it was indeed slightly bent compared to the new one) 10 minutes later he drove the car around and told me everything was 100% fine.

I've been driving the car now for a week or two and I am obsessing over every time the car shifts. Did that feel right???? Did that shift funny??? I only drove the car maybe 30 miles with the bad filter in, maybe 28 on the highway and 2-3 miles on local roads. Could the transmission have been damaged in that time? I did not do any driving that I would consider aggressive in that period. The car seems OK but I'm obsessing to the point to where I need some reassurance from someone who knows a bit more about cars than me.

Please help!! I think I just need someone to tell me I'm imagining things and to relax but if it really is something I need to worry about, please let me know.

Thanks a ton,
Scott

 

I had a similar incident with my wife's 94 LHS.
The odd morning it would take a few seconds to engage drive. Besides that it was 100% fine. Didn't feel like even looking into it because it was only the odd time.
The odd time but it was occuring more often.

I let a transmission shop tell me it needed a trans. Next shop took it for a road test with their computer hooked up to it. He said it shifts great and for a car this old all the numbers on the computer looked great.
He suggested we drop the pan and have a look.
With the option of just replacing the entire trans. I like the idea of looking first.

Found an incorrect filter in there. Also allowing air to get sucked in. I put that filter in there over a year before that.

Anyways. That was over 5 years ago. The car now has over 270,000km and it's still working fine.

 

If it had damaged the transmission he would have been able to tell when he pulled the pan to put the other filter in. It would have had an excessive amount of clutch material in the pan. That and there is no WAY he would have let the possibility of a transmission R&R slip by him, espescially since you have a warranty on it. Guaranteed money for him. I wouldn't worry about it now but definately take it back in for another transmission service BEFORE your warranty expires just in case.

On a side note, if he has been in the business for 40 years he should have known to take the car for a short test drive after working on it just for reasons like this. He likely would have caught the problem and been able to fix it without looking like an ***. ANYTIME I work do anything to a customers car I ALWAYS take it for a test drive to make sure they are getting it back in proper working order.

 

When he took the pan off I think he was expecting junk in the fluid, said he saw it all the time on police cars he worked on because they wrecked their transmissions but he said my fluid was clear with no sediments in it. So does that mean I'm probably in the clear?

 

Sounds like it to me.

 

sounds like your just nervous if it's shifting fine now i wouldn't worry. it just wasn't able to get proper line pressure to shift before and was going into limp mode. pull the dipstick and smell the fluid yourself if it smells burnt real bad worry otherwise i wouldn't worry a bit

 

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