OhEightGT

Mine had decel whine stock, and does now as well, but it can only be heard if the back seats are down, and I have the clutch in so it's idling... I hear people say that cars should have absolutely no gear whine, but I have known people who have had gear whine for the whole life of their car/truck and never had an issue mechanically. If it's unbearably loud, I'd say something is definitely wrong. If it's just enough to be audible, something may be wrong still but lots of people have that and few of them have any trouble in the end.

Anyway, sounds like you've got it figured out, and I really hope you can get it to go away or at least get quiet enough that you can stand it!

CutterWolf

Hard to say whats wrong but most of the time it has to do with the backlash and shim's. There are of couple of guys here in AL that can install gears with out any whine what so ever. One of them happens to be a ex-SVT tech who still has his special tools and all, but this guy can tell what shim's to use and what direction they need to go in at just by feel alone.

madmann26

The guy that did my install is also a fellow Mustang guy.

He set the pinion pre-load by hand first. At first, I asked him if he was going to use the gauge, he laughed at me.

He measured the pre-load when he was done, it was perfect. He went ahead with the install and painted the gears to get the bite mark and ended up changing shims 2x, after that, the bite marks were perfect on the drive/coast side.

At least compared to the stock 3.55's, he was curious and looked at the bite pattern on those.

I have a very slight whine, but I only notice it if I am concentrating on hearing for it, else, I don't even hear it.

If it's audible and noticeable, chances are the pre-load may be wrong.

The only thing that was changed out on mine was a new pinion bearing.

BlackBeauty4.6

Yea we'll figure it out tonight or this weekend.. We're gonna check the paint see what it looks like.. But most likely what i have to do is shim the pinion.. Which sucks cause the whole damn thing has to come out wish it could be like some Dana 60 rear ends where you tighten or loosen either to set backlash and crap

timmbo

I've seen this a million times on this forum about 4.10's whining. 99.999% it's shadetree ignorance or crappy shops. You have to know what your doing. There is nothing easier IMO than installing a Ford Racing gearset in a late model 8.8 Ford rear axle. Reason? They are made as a direct drop in so you can utilize the same two cast iron carrier shims and the single shim under the pinion bearing. Where people *** their installs up is NOT getting the correct pinion bearing preload by not putting enough or too much torque on the pinion bearing crush sleeve. I've installed several gearsets in my lifetime including the one on my GT and it's quiet as a mouse. You can't just throw these gear sets together without using a dial torque wrench to properly monitor pinion bearing preload with the carrier out of the housing. Nor can you check for proper backlash without a dial indicator. However, if it weren't for gear drama and blinker fluid threads on here I'd get awfully bored LOL!

Good luck with yours.

BlackBeauty4.6

Yea myself and my good friend both new that the gears are direct drop ins and we replaced the single shim behind the pinion bearing with one single shim torqued her down etc etc I think just what happened is we over looked one part a little fast and there is where we screwed up till we pull the housing back off and check the paint we will not know to shim the pinion (which is what I think) or re torque the bearing etc etc.. Just hope it's a simple fix

lenko

Anybody thinking that gears are a "direct drop in" could be wrong. Some can be dropped in and some can't. The pinion head thickness varies. If close it may work but if not it won't and they will whine. Installers should used the master housing dimension - measure the pinion head of the old gear set and see what the thickness of the pinion shim is and then measure the new pinion head to determine the difference to see what pinion shim should be used. Once determined you should start with that new shim and start checking the gear mesh pattern to get it dialed in right. A honed out pinion bearing is useful to slip on and off when checking the pattern so you don't have to press the bearing on and off to change pinion shims. Anyone changing gears might want to check out Adkins gear install which explains the MHD and formulas to use. Have done a number of gears installs this way to get them dialed in right. See http://www.superstallions.com/tech/d...ars/gears.html

Lot of people concentrate on the backlash which is important, but if its somewhere between 7 and 15 thou., it's probably all right. Mine usually vary between 9 and 11, which I feel is just right. Also important is pinion preload and someone has to be VERY experienced to do it by hand and feel. I certainly wouldn't be trusted to do it that way. The install can very tedious and time consuming as measurements are not necessarily that easy to make depending on your tools and methods. A lot of reading and research is advisable.

mjr46

Gear sets are not made to be direct "drop ins" as stated, I have ford racings oem instruction set that used to come with every gear set they sold and it specifically states using proper methods to install, now in some or maybe alot of cases the oem shim set can be reused, I have done it, only after checking that all is in spec, and I keep a record of all, and the last 6 done, spec with oem shims for backlash was .006 , .014 , .003 , .009 .019, .018 as you can see, only one fell within spec, moral is, always use proper method for install, heck even after such I've encountered probs, on one I did, it made a gosh awful thud sound everytime it was rotated, upon disassemble we saw a few teeth on the ring gear that had not been machined properly. so I've seen some wierd stuff in the many installs I've done