Six7One

So this "new to me" 2013 V6 Premium with auto tranny and 9450 miles has a "clunk" when coming to a slow stop. It seems to happen RIGHT when the car is about to stop. And maybe, when I slowly roll out.

This is my first Mustang. Can someone with more experience with this *awesome* car share their opinion on whether this is a problem or potentially a problem?

Thanks.

kylerohde

That's a weird one but at least you're still under factory warranty; take it in man.

ArtU

Hi, I have this happening since day one, and and have almost 15K on my 2013 V6 Premium now. two ways it clunks I have found out. Slowing down to a car in front, as you move very slow one of two things happen. The trans bumps you forward as it downshifts into 1st gear.

If is doesn't down shift into first gear, you get a clunk in the read end, u-joint or some other device making it. I can do a test to make it happen any time, do this. Put it in sport mode and in an open parking lot select 2nd gear and keep it their. Move to about 7-10mph and let off the gas "clunk" and put some in very little "clunk" and let off a little again "clunk." I was just doing this test yesterday and began more concern on the issue now.

Previously for the first issue we were told to let the trans "re-learn" itself from pulling a fuse in the fuse box for 10mins. But it does come back again and not a fix. I will ask about it at the next oil change.

FordService

I recommend you have them checked out at your dealer as soon as possible, guys. Then, PM me with your VIN, dealer, full name, mileage, and best daytime number so I can escalate this to the customer service manager for your area.

Deysha

rockazona

Deysha, if you are on still on this forum and thread, I have the same issue. I've been to 2 dealers. They're friendly but no resolution. I even escalated it to Ford customer service. For all of us that have the automatic, I don't think it matters if it's a V6 or GT, there is a clunk or thud when the trans is downshifting into 1st gear and it's very noticeable. Every automatic has a bump downshifting into 1st gear but this car has a clearly defined thud. There is also a click or clunk when accelerating at low speeds. These are known issue with the Mustang auto trans but there is no bulletin and Ford is doing nothing about it.

I've talked to mechanics and service managers at both Ford dealers and they tell me it's normal. I agree to disagree. One of the dealers contacted Ford for me and they said the thud on deceleration at low speeds is normal and the clunk on acceleration is lash in the driveline and again it's normal. Every automatic is going to have a bump decelerating into 1st gear but this is a clearly defined thud. There may be no fix for it. If you tap or ease into the gas pedal at about 20 mph, when coming to a stop, you will feel 2nd gear tip over into 1st and when you come to a complete stop there is no thud. It's an adjustment to the shift point on deceleration.

I did a test drive with 2 mechanics. One of them said it was just a hard downshift and explained it downshifts into 1st gear below 3 mph. I believe if it downshifted at a higher speed it would solve this problem. I'm going to try a performance tune and see if Bama can set the downshift into 1st gear at a higher speed because Ford is doing nothing about it.

kylerohde

She is but you'll get a faster response if you PM her.

jc46002003

All,


The little 'bump' you feel when coming to a stop is the tranny shifting back into 1st gear. It's completely normal. I've had 4 mustangs since 2010 all 6r80 and they ALL do it. One thing that will make you feel it more is excessive gear lash in your rear end. I had this and it was making the downshift feel really sloppy. If you're hearing metallic noises and it's not gear lash, could be a carrier bearing or something actually wrong with the tranny. 6r80s are very good trannies.


However, the clunking sound when starting off, I've never had that before. A lot of these mustangs I've had have had excessive gear lash. My current one just got out of the shop for it. They found pre-mature wear in my limited slip disks, high gear lash, a scratch on one of the bearing races and a bad bearing, all in the same rear end! Only 2500 miles! It was causing a decel vibration and LOTS of noises. It's now solved but now it makes a crazy moaning sound...I'm taking back in tomorrow...

JohnnyMustang2

I have the same problem on my 2013. Do you ever get this fixed and what did they do?

JohnnyMustang2

I have this problem with my 2013. Do you ever get this fixed and what did they do? Did you ever get the after market retune?

RIBS

My 13 V6 did this when new. It has gone away now that the car is broken in-I have 25,000 miles.

JohnnyMustang2

I'm having the same problem on my 2013. I spoke to someone who installed the G-Force chip on a 2011 and it remedied the problem. I understand they can set the shift points to your liking. Did you get the Bama tune and did it fix the problem?

fast frankie

I have the same issue with my 2013 V6 auto trans. Dealer says it is normal and nothing is wrong. I have had automatics before (GT V8) but did not have the issue. The service manager said "every auto trans does the same thing" I did not agree with him as this is not my first auto trans and he was getting testy with me so I left.

FordService

You’re welcome to bring it to a different Ford Dealer for a second opinion, fast frankie. It may help to get a fresh pair of ears/eyes on it. Let me know if you do.

Deysha

rockazona

I PM'd Ford Service. We'll see if I get a response. I've already called them. All you get is unknowledgeable peeps telling you to contact a dealer. When I was a kid I owned a 71 Cuda. Think I'm going back to Chrysler. I owned 2 V8 Mustangs before the V6 I have now and I know some idiot is going come along and tell me how I should have bought a manual V8. Already been there. Neither one of my V8s had this issue with the clunk. A month ago I blew out the main seal on this car. I'm done, by the end of the year this car is gone. I've been to 2 dealers who just blow you the f off and tell you it's normal. I've never owned an auto that slams into first gear on the downshift with a clunk. So, I turned to Bama for help because Ford isn't doing sh*t to help. What a circus that was. They don't understand what you're asking. It took 3-4 weeks to get a tune. None of the tunes they sent worked. I asked them several times if a 1 piece aluminum drive shaft would fix this problem and they never responded? I'm not going back there. Wasted $400. I've done everything I can think of. If anyone one this forum knows the fix, I'm all ears.

rockazona

I want to follow-up on my previous post about the clunk. I think I finally got it figured out. It took me almost 2 years and about 40k miles. There are a lot of threads and posts online and no one seems to have an answer. I was determined to find a solution. I had an e-mail forwarded to me from a Ford engineer and he said there is more tolerance in the drive line than other manufacturers. The obvious follow-up question was why. The answer was to protect the components. I don't agree, too tight and too loose is not going to protect anything. With my car I think the rear end is too loose. I owned two 5.0s before the V6 and I put a 4:10 in one of them. I know about it. A loose rear end, a 2 piece driveshaft and the transmission downshifting hard into first gear is the problem. The car takes the load off of the drivetrain when coasting to a stop. It downshifts to first gear between 0-2 mph with a heavy metal on metal clunk.

I also couldn't do a burnout when I bought this car. Ford installed this brake over acceleration (BOA) crap in the car. If you have your foot on the brake at WOT it will cut out at 2000 rpms. This came from litigation over the throttle sticking in the Toyota Rav4 some years. So, Ford decided to put this safety feature in a muscle car. It affects both the V6 and V8 auto. To do a burnout you have turn off more than the traction control. If you hold down the traction control button more than 5 seconds with your foot on the brake and in gear then it will turn everything off. At that point the 11 & 12 model year could do a burnout but the 13 & 14 still had the BOA crap. You need a tune to override it.

I called around to few places that offer tunes and I remember one place wouldn't do business with me because they couldn't guarantee the burnout. I called Bama and they said they could. I was skeptical and when I got the first tune I couldn't do a burnout. You can guess what that return phone call sounded like. The guy I got on the phone said they forgot to do something. They're not going to tell you how but they can do a lot more than we can on the hand held device. The second tune took care of the burnout but I still had an issue with the clunk. We went back and forth with several tunes changing shift points but couldn't get it right. I bad mouthed them on a previous post but had good reason. The last tune I ordered back then was for 91 octane and they sent a 93 tune when I can only get 91 octane. They said it was ok to run it like that. The changes they made were good so rode it that way for a while. A week ago I saw an ad online for the new device and one of the parameters that could be changed was the shift points. I called and got the right dude on the phone. He was on his game and delivered. It comes down to getting the right person. I finally got a good tune. You really can't change the shift points with the new software. You can change the shift points at WOT by a few mph and change the shift pressure up to 25%. They reduced the shift pressure on the downshift to first gear and I maxed out all the pressure on the upshifts.

I finally fixed the burnout and clunk problems. If you really want to do it right then install a one piece driveshaft and change the rear gear with the Bama tune. Why can't Ford figure this out? One of the dealers I went to tried to help. They replaced the driveshaft but I knew it wasn't going to work. Me and the service advisor looked for clunk bulletins and found one for the F-150 with the same motor and transmission but nothing for the Mustang. Maybe this will help someone save time. It worked for me.

Ronald Dale Moody

tell the dealer if it's normal.to let you test another mustang of same model to see if it has the same thud or clunk.