[Regency 2007]

I got my Ford Racing 4.10 installed today. I wanted to ask if there is any break-in because the guy that installed it has built several fully built mustangs for racing and said just drive it like normal and you can run it wide open if you want...

Also I noticed there is a slight gear whine that gets a little louder the faster you go, is this normal? will it go away or decrease over time?

It isn' horrible or anything, I have heard a bad gear in my dad's f150 and it was 4x's worse...

[raycutchins]

I have the FRPP 4:10 gears and have not heard a whine or any noise from the rear.

[Regency 2007]

hmmm..... maybe I will take it back to him in a week or two if it doesn't stop, I would say the car feels like it has another 30RWHP after taking out the 3.31's I just need to fix the motor, it is so FLAT! nothing compared to my Mach1 I sold

[PaperCross]

Regency, did you put in a tune for the 4.10 gears?

[Regency 2007]

not yet, speedo is way off! Its somthing like readout 65 but I am going 40 or something like that, I am waiting for a tuner

[PaperCross]

lol...ok...i am getting my 4.10 in this weekwnd....i was asking because i wanted to recliberate the speedo and the tune when i put it in....

[MustangMatt]

I was told to take it easy for 200 miles. Could drive fast, no hard launches. Let them heat cycle. As far as noise, you should not have any at all. They should be just as quiet as your factory gears were.

[Regency 2007]

The guys over at Mach1 registry said it is fine if the 4.10's make more noises than the stock gear. He said it is in there turning alot faster and moving oil alot faster so it will cause more noise...

[MustangMatt96GT]

But it really shouldnot be heard! That may be true, but the install is what decides the noise of the gears!

[MustangMatt]

Mine make no noise at all. That is the way it should be.

[Emay]

Regency,

Gears are not supposed to make noise. There are several manufacturers out there that make gears that do whine a lot, mainly due to how the pitch their cuts.

FRPP makes their gears silent, motive gears are notorious to be loud. Most people don't want to hear new noise in their 25K+ car, regardless of performance gain. Us people running 3.73's and 4.10's on the street should not hear any difference when driving around, options are there for quite gears.

That said, take it back, the installer knows they should not be noisey. Excess fluid movement does not equal gear whine. It's poor set up of the pinion to the ring gear most likely.

As others have said above, they have zero whine and that's how it should be.

[flattusmaximus78]

Theres nothing wrong with your gears, or the install. Some gears whine, end of story. It's not of any concern.

[Emay]

I disagree with every bone in my body Nick, however it is a free world and you are entitled to your opinion.

[orangeRcode]

The taller the gears - 4.30, 4.56, 4.88 the more likely you will have some noise. It also has to do with how tight they are set up. That being said, manufacturer select can make a big difference. My FRPP 4.10s don't make any noise.

[07gtmustang]

I was a mechanic for a Ford dealership for 5 years there should be no noise if there is now its just going to get worse

[05mustang_kb_charged]

Does the rear end get hot? After driving for a while check the temperature on the rear end by touching with your hand? But be cautious it can be really hot if the gears are tight. I left my finger prints on my Z28 when the gear installer told me to touch and see how hot i was before i brought it back. Had 4.56's and they were whining bad after the install.

[Regency 2007]

so it should be cool to touch after driving around on a normal car?

[05mustang_kb_charged]

not exactly outside temperature because you do have a lot of friction with the gears but it shouldn't be so hot it will give you 3rd degree burn either.