Wont move in neutral

[Trevian26]

Hello,
I drive a 2006 Mustang GT. A few months back I had a Ford Performance 3.73 gear kit installed by a shop onto my stang. I do a lot of driving (hwy/city) maybe two weeks in, I start to hear a slight whine coming from the rear portion of my vehicle. I heard it in all gears but obviously the faster/higher gear I’m in, I think it just drowns out by engine/exhaust noise. If I am coasting to a stop sign in neutral I also hear it.
Anyways, thought that noise was normal after doing some reading of fellow Ford performance gear users.

Now onto the issue, recently while driving I am pulling out of a red light and I get to 3rd gear, I notice that I am slowly losing speed/acceleration although I'm on the pedal. Not even 5 seconds later, I hear a few loud clunking noises coming from under/behind me. So I throw it in neutral and try to coast to a safe side road to park. As I am rolling WITHOUT APPLYING BRAKES I am going 5ish mph, the car just stops, like completely stopped in its tracks as if I slammed the brakes. While it is still in neutral and no parking brake, I try to see if I can push it and no luck.

I get the mustang towed and however the vehicle now wants to roll in neutral. Its like it picks and chooses when it wants to be able to move. I can start the mustang up. I some how was able to put it in first and reverse when moving it onto my driveway but havent touched it since.

I bought myself a DD and want to do the work myself even if it takes forever cause I love the car and love to learn. Id really appreciate some places to start diagnosing. I feel it could be rear end or possibly tranny? I do beat on the car a lot.
Thank you for any help.

 

[StockishS197]

Can you place the trans into each gear?

Given the work was done recently in the rear, the noise and clunk, I would pull the rear dif cover and investigate.

 

[whitmanink]

well for starters i just installed 4.10 ford gears in my car, no noise whatsoever.
you shouldnt have noise either.
other brand gears sometimes have noise but thats mostly set up mistakes,,

so the install is wrong,, the fact it got worse tells me somthing wasnt tightened down properly or not shimmed properly ..

but its odd it "locked up" and then freed up again (almost like clutch problems)

first thing id do id rip off that diff cover... im sure the gear oil is nice and grey from metal in it.
but you wont know until you do,,
but id say at least your gonna need is a new gear kit with shims and bearings . and a new lsd rebuild kit at a minimum..

seals should also be replaced,,

but again you wont know until you rip it apart

 

[Trevian26]

Can you place the trans into each gear?

Given the work was done recently in the rear, the noise and clunk, I would pull the rear dif cover and investigate.

Yes I can throw the shifter into every gear. When I was moving it around in my driveway in first gear, I barely left off the clutch because it seemed like the more I let off of it, I can get a sense of strain/hear the the clunking noise start to happen and then obviously the car would stall out.

 

[Trevian26]

well for starters i just installed 4.10 ford gears in my car, no noise whatsoever.
you shouldnt have noise either.
other brand gears sometimes have noise but thats mostly set up mistakes,,

so the install is wrong,, the fact it got worse tells me somthing wasnt tightened down properly or not shimmed properly ..

but its odd it "locked up" and then freed up again (almost like clutch problems)

first thing id do id rip off that diff cover... im sure the gear oil is nice and grey from metal in it.
but you wont know until you do,,
but id say at least your gonna need is a new gear kit with shims and bearings . and a new lsd rebuild kit at a minimum..

seals should also be replaced,,

but again you wont know until you rip it apart

That’s honestly the route I was thinking. With it in neutral versus clutch in, I still got the same results at the time (aka no movement). The whining noise also seemed to slowly get louder over time. I want to crack the case open this weekend.

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^^^^
This along with fluids and FP 3.73 gears is what I had asked the shop to install. If this is the issue would I just have to reorder said things or is there more?

 

[JC SSP]

Some shops will not warranty customer supplied parts, so it all depends on if they provided a written warranty.

I suggest you conduct or take it some place to do an inspection. I would NOT drive the car; you might damage it further.

I have seen the small cross-bolt pin come out and cause the spider gears to bind and clunk, but you won't know until you remove the cover. Post pics of your findings.

 

[bambam 06]

That’s honestly the route I was thinking. With it in neutral versus clutch in, I still got the same results at the time (aka no movement). The whining noise also seemed to slowly get louder over time. I want to crack the case open this weekend.

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^^^^
This along with fluids and FP 3.73 gears is what I had asked the shop to install. If this is the issue would I just have to reorder said things or is there more?

I would take it back to the shop that did the install and let them fix it. You paid good money for the job, let them worry about fixing it.

 

[Trevian26]

I would take it back to the shop that did the install and let them fix it. You paid good money for the job, let them worry about fixing it.

Do I have any grounds to do so considering the installation was back in May? Im not opposed to doing the work myself and kind of worried they’d f up again

 

[bambam 06]

Do I have any grounds to do so considering the installation was back in May? Im not opposed to doing the work myself and kind of worried they’d f up again

I don't know what the law is in Ga, still i would take it back to them. The 1% work that i allow others to do, i must be present and observing the work, otherwise they are not touching my car.

 

[Trevian26]

Another detail I forgot to mention (sorry). That whole incident happened on the attempt to go home from work. That morning to work however, I noticed that ONLY when I take on right hand curves the front end of the vehicle shakes, particularly the driver side. I do remember it had to be also above I think 40 or 50+mph for it to happen as well.

A good example that I remember, Im traveling on I95 going 80mph and I’m coming up to a slight right curved portion of the interstate. I will start to feel a crazy shaking on the driver side only and hear thumping. Similar to as if I'm going over multiple pot holes on the front driver side wheel. The problem isnt replicated if I was to drive on the opposite side of the interstate (left side curve) traveling the same speeds. I brushed it off for potential tie rod (alignment was ever so slightly off to the right) or wheel bearing issue but could this problem be related to my LSD cooking itself? Maybe bad clutch pack inside the differential and the vibrations carried over into the front end of the vehicle?

 

[whitmanink]

im gonna say your gears are not installed right at all , the cross pin mentioned above is one of those things that need to be tight.. (proly isnt)

what your describing is definitely in your rear end,,

the lsd is definitely messed up as well,

but you will need
** a new gear and bearing\shim\seal kit,
***a new lsd rebuild kit,
****ford friction modifier and 3 bottles of gear oil

its safe to say your gears are prolly toast ,, but you may get lucky but seing how the noise got worse ,, im gonna go with all new,

being as you are out soo long from when you had them installed ,, theres no way they will warranty it, you would have had to go right bac that day or the next.,.
again no gears should make noise if they are ford and installed correctly

 

[Trevian26]

im gonna say your gears are not installed right at all , the cross pin mentioned above is one of those things that need to be tight.. (proly isnt)

what your describing is definitely in your rear end,,

the lsd is definitely messed up as well,

but you will need
** a new gear and bearing\shim\seal kit,
***a new lsd rebuild kit,
****ford friction modifier and 3 bottles of gear oil

its safe to say your gears are prolly toast ,, but you may get lucky but seing how the noise got worse ,, im gonna go with all new,

being as you are out soo long from when you had them installed ,, theres no way they will warranty it, you would have had to go right bac that day or the next.,.
again no gears should make noise if they are ford and installed correctly

i was thinking of purchasing these if what is said is the issue. I already have the fluids in hand. Just curious if these two purchases would cover all the basis and if so can I reuse my gear set or do I need to buy that new too.

Ford Performance Mustang Traction-LOK Limited Slip Differential with Carbon Discs; 31 Spline 8.8-Inch M-4204-F318C (11-14 Mustang V6; 86-14 V8 Mustang, Excluding 13-14 GT500) - Free Shipping

FREE SHIPPING! Limited Slip Differential. Is your stock rear end leaving you in the lurch? Then you need to upgrade to a Ford Racing 8.8 31 Spline Traction-LOK

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Motive Gear Mustang 8.80-Inch Rear Differential Bearing Kit with Koyo Bearings R8.8R (11-14 Mustang V6; 86-14 V8 Mustang, Excluding 13-14 GT500) - Free Shipping

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[86GT351]

Did the injstall shop give you any implied warranty? Even if the customer suplied parts there is still a labor guarantee.

 

[Trevian26]

Did the injstall shop give you any implied warranty? Even if the customer suplied parts there is still a labor guarantee.

No they didn't and what sucks is they are the only shop within 30min that had a reasonable quote that wasn't thousands of dollars.

 

[Eman]

Have you spoken to the shop that did the job? See what their policy and attitude is. If you feel comfortable letting them work on it again let them fix it. Or if you don't want them to work on it find someone who you feel comfortable with or if you can do it yourself. Skip the law, lawyers and arguments, life is too short.
If you do it yourself, take pics and document as you go for your own reference and to post your findings so you can get advice. I wouldn't buy any parts until you have it disassembled and cleaned/inspected.

 

[Trevian26]

Have you spoken to the shop that did the job? See what their policy and attitude is. If you feel comfortable letting them work on it again let them fix it. Or if you don't want them to work on it find someone who you feel comfortable with or if you can do it yourself. Skip the law, lawyers and arguments, life is too short.
If you do it yourself, take pics and document as you go for your own reference and to post your findings so you can get advice. I wouldn't buy any parts until you have it disassembled and cleaned/inspected.

Im probably going to just do it myself. A few weeks after the job I had questioned the slight humming noise and the brushed it off as a “sounds like a tire or suspension issue” even though I stated it started happening after their work.
Time and work isnt an issue for me, id honestly love to learn and to some degree money matters. I got myself a DD now so im ready to take on multi day projects now with it.

 

[whitmanink]

i was thinking of purchasing these if what is said is the issue. I already have the fluids in hand. Just curious if these two purchases would cover all the basis and if so can I reuse my gear set or do I need to buy that new too.

Ford Performance Mustang Traction-LOK Limited Slip Differential with Carbon Discs; 31 Spline 8.8-Inch M-4204-F318C (11-14 Mustang V6; 86-14 V8 Mustang, Excluding 13-14 GT500) - Free Shipping

FREE SHIPPING! Limited Slip Differential. Is your stock rear end leaving you in the lurch? Then you need to upgrade to a Ford Racing 8.8 31 Spline Traction-LOK

www.americanmuscle.com

Motive Gear Mustang 8.80-Inch Rear Differential Bearing Kit with Koyo Bearings R8.8R (11-14 Mustang V6; 86-14 V8 Mustang, Excluding 13-14 GT500) - Free Shipping

FREE SHIPPING! Better Vehicle Performance. If you need to replace or upgrade your ring and pinion, the Motive Gear 8.80-Inch Rear Differential Bearing Kit with

www.americanmuscle.com

yea that will all work,, altho i dont know if your gears will be reusable ,, dont know till u crack that diff cover off

 

[Trevian26]

While I havent cracked open the differential, I have came across some new information that might be of help. I had to roll the stang while in neutral to slightly get it out the way for me to roll out my generator. In doing so, car off, hand brake down, in neutral, me and someone else managed to move it forward maybe 4feet?ish then I hear a CLICK sound like as if something engaged because right after mustang stops itself dead in its tracks and no longer wants to move forward or backwards again. After a long while of it sitting, I crank it up. Just a simple hand brake while in neutral, no clutch. Cranks just fine, I rev it freely too. First gear clutch down, I can rev freely as well. When I throw it into first and ease off of the clutch it slowly starts to die down the more I left off the clutch, aka stall, but its not moving forward. I put it into reverse and ease off of the clutch and it actually slowly moves backwards. So I am starting to think its not a differential issue and something related to whatever click noise I heard preventing it from going into first.

 

[Trevian26]

Lifting up the rear end, both tires rotate same direction. When in neutral, with force I can rotate the wheels. Once I dropped the car, somehow once again I could roll the vehicle forwards and backwards in neutral. Then I tested what happened if i am on the clutch in first gear, and it then stops in its tracks with someone trying to push forward or backwards. All of this is with the engine off.

 

[Trevian26]

Lifting up the rear end, both tires rotate same direction. When in neutral, with force I can rotate the wheels. Once I dropped the car, somehow once again I could roll the vehicle forwards and backwards in neutral. Then I tested what happened if i am on the clutch in first gear, and it then stops in its tracks with someone trying to push forward or backwards. All of this is with the engine off.

Lifted up rear end again and tried to spin the rear tires and it budges like an inch or two forwards or backwards. Any guesses? Is it still differential or is it something else.

Judging by the car stalling out when l let off the clutch in first is telling me, my transmission is at least engaged into first and also can go into reverse.
I read somewhere of someone with a manual transmission having an issue that could also be a possibility (attached). When it initially broke down I believe I was in third gear when it happened.