So I usually do more reading than anything around here .. Although now, I'm reaching out for help! I've got a 2013 5.0 that came with 3.15's ... Personally, I didnt care about this seeing as I drove 4 hrs to pick the car up simply because I wanted a certain color / automatic ~ lol .

Well, the guys talked me into putting the 3.73's on my car telling me that I would NOT need a tune. Even the shop that installed the gears said it would be fine with no tune on it (still have the msg in my phone.) Wrong! It drove ok for a couple of months and then ... this is the part I'm not sure how to explain. I thought the transmission was slipping, the guys said the shift points were off. You could hear when the car tried to go from 3rd to 4th it was actually trying to downshift. I was told a hand held tune / tuner with the 3.73 gear ratio preloaded tune would fix this. I got the tuner, loaded it up ... ran like a champ for a month or so, yesterday, started doing the same thing again.

Does this sound like anything you guys have experienced before?! My fear is that it IS something in the transmission and now that the tune has been put on it, the dealership is 'gonna laugh at me regarding any kind of fix ... even if we set the car back to stock.

Help!!

 

It is absolutely imperative to tune an automatic car that has had the rear gears changed.

Had you asked here beforehand we could have saved you some grief.

Don't know exactly what has happened on your car, whether the lack of proper tuning has caused transmission damage due to the misoperation from the incorrect tune or if it some other issue.

 

Yeah, I probably should have asked here beforehand ~ but I thought the owner of the shop, that put the gears in, knew what he was talkin about. Like I say, I still have the convo where he said i do NOT have to have a tune.

I called Bama and they told me they are as puzzled as we are on why the tune would have fixed it for a month or so and now it is doing it again. He suggested that unhooking the battery and leaving the high beams on for 20-30 minutes?! He think thats the car is trying to go back to what it 'learned' and was used to?? Maybe that makes sense to you guys?! He also said to set it back to stock and re-upload the tune after we do the 20-30 minute light / battery trick?!

 

It is pretty difficult to really understand some of your comments, but there are a couple of things that would be worth trying. Drive it out and put it in "selectshift" mode and see if it appears to automatically shift OK. You should also try disconnecting the battery for 15 or 20 minutes, then reconnect it and try driving to see if the shifting is OK. If none of that helps, I'd restore the stock tune and drive it for awhile then take it into the dealer for diagnosis. Frankly, just the installation of the 3.73 gears on with the automatic probably was enough for them to deny a warranty claim on the transmission, and certainly the differential. Try the other two approaches first to see if the transmission controller just needs to be reset. Given that the tune changed the situation before, it doesn't sound like a hardware issue, but that is just a guess.

 

By select shift, do you mean like 'manual transmission' ?? Cause if you drive it in that, it does fine.

And I'm sorry it is hard to understand .. its hard to 'say' what its doing cause its all in how it sounds / feels. Goin into 4th it sounds like the engine is reeving up, but the car isnt going anywhere .. And that is why my friend said it is actually downshifting - you can hear it, it gets very loud and there is slight hesitation before it catches the next gear and goes.

Gotta love these 'friends' that suggest these awesome idea's pretty much knowing that I dont know any better ... and ... well, yeah ~ now I'm having to deal with whatever is going wrong! 400 gear swap ... 400 to fix the issue that the gear swap caused ... Good for a month, now back to the drawing board.

 

Actually, I meant to put the automatic transmission in "Sport" mode (S). Don't shift it with the switch on the shift ****, just let it shift automatically and see if the shifting is OK. Drive it in that mode for a day or so - if it is OK - and then go back to drive (D).

 

Well, the ppl at Bama told us today to put the high beams on, unhook the battery and leave it like that for 30 minutes and then upload the tune again (force a download cause nothing has 'changed' and it would notice that.) So we did ... and ofc it asked if we wanted to force it, so we did ... now its back to running like a champ! I dont get it?!?

 

PS ~ thanks for the help you guys, I appreciate y'all takin the time to reply!!

 

Well, at least if it does it again you know now how to fix it.

 

Since you had this problem with both the stock tune and the BAMA tune, chances are there is an electronics issue with the transmission. There were other problems with the "transmission control unit" earlier....

http://mustangs.about.com/od/product...rol-Module.htm

If the problem occurs again, there may be an issue with the transmission control module - which has its own memory system. Not sure how to get FORD to pay for that, but you might want to keep it in mind if it does occur again - or if it "fails hard."

 

^- oh wow!! Great information!! I really appreciate that! I'll have to mark that page as a favorite. Every since we forced the bama download today, its been acting fine, but then again, it did last time as well. The guy at bama told me today it sounds like it was trying to back to the 'old memory' ?!?!? So since this is the second time we've done this, it would sure be nice for it to override (and stay that way) the problematic issue.

I've got a really good friend that knows about what it is doing and knows I had to put a Bama Tune on it to fix it. When it started doing it again yesterday, I called him freaking out that something in the transmission had been messed up and worried that warranty wouldnt fix it due to the gears / tune but he told me 'he's got me covered' ... Granted, who knows if in the end that would really be the case!!!