Installed 4.10's and got a problem.
 

Had some 4.10 gears installed in my 99L and now I have this high pitched tinny, ringing noise both on acceleration and decelleration. Replaced the pinion bearings and still there. The mechanic said it sounds like a drive shaft resonation to him and that the 4.10's just might have this sound as a rule.
Anybody else have this problem? it is pretty loud.
Chris

Stormyday, please post your findings on this issue. I am thinking on putting a 4:10 in my 2000L this spring.

Peace, Suavy

Had mine in since early 2000 on my 99 and no ringing. Sounds more like they are not setup right. To much gear contact on the leading edge.

I'd second that. Just installed a set of 4.10's on the Cobra and no noises there.:thumbsup:

sounds like gear lash..like they said.

im slightly retarded.. can you tell me what my 2001 has? can i switch to 4.10's for any gains, and what would they be? :help:

Krix you go 3:73s in your truck and I dont think your gonna notice as much of a gain for the money going to a 4:10 unless u do alot of drag racing witha 28 inch tall slick. Most people tht do this mod have the 3:55 gear ratio I think! But dont quote me on any of this info.... I THINK i am sumwhat right I a not sure!! LMAO!!!:p :p

Re: Installed 4.10's and got a problem.
 

Did he mark the drive shaft before he took it off and re-install it in the same orientation? I know the drive shafts are balanced, but I have seen where there are vibrations from not installing the drive shaft exactly the way it came off.

4:10's shouldn't make noise. If the pinion gear was not torqued properly, or the backlash was not checked, you may hear a gear whine on deceleration. That is more likely it. If you get it redone somewhere, I would take it somewhere else.

Paul

Krix, you already have 3.73 gears in your '01. I would not recommend switching to 4.10s, there are just too many potential problems. The factory ecu cannot by calibrated without a chip, which will void your warrantee.

Slightly different question but on same topic. How much did the install cost you. Does anyone else chiming in on this thread have this info. I have the gears, just need the install. 3.73's by the way if that matters.

BD

too much backlash.....
 

have them double check the backlash right in front of you with a set of feeler guages......what is the correct setting.....??? Why is .005 comming to mind??

Backlash is usually .006-.008. On the Ford Racing gears, they like it more around .010-.012 to allow more fluid and more cooling.;)

it is possible that the setup was not done correctly. this is something that most people don't understand. A LOT of so called ring and pinion installations are just that, installs, not proper setups.

there are alot of precise measurements to make that often get skipped.

people just reuse the side spacers (affects backlash), people just reuse pinion depth shims (affects pinion depth), people tighten pinion nuts with an impact gun (affects bearing life and pinion bearing preload).

there is alot more to it than you normally get when somebody slaps a set of gears in for $150 bucks.

having said that, it is possible that it is just a noisey set of gears.

I have a 4.10 set (not that it's a problem with 4.10s, it's just purely coincidental) in the 9" rear of my LX Mustang. it is noisey as crap. it has a noticeable whine on both coast and decel. these gears came came already setup in a brake to brake axle assembly from Strange engineering. I always thought there might be a problem, so I took the whole thing apart myself and checked it. everything is perfect, it just happens to be a noisey gearset. changing from synthetic to conventional 80-90w gear oil helped my noise concern slightly, but only slightly. you need to ask the guy about the backlash, pinion bearing preload, and pinion depth measurements. or ask him if he just threw the gears in there.

good luck.

later,
chris

Thanks for all the replies guys. My installer has been doing gears for 19 years and checked everything erfectly, in fact after the first test drive he took averything back out changed the pinion gears and reinstalled everything again.
Still had the noise.
The gears are from US gear, is it possible that it is a bad set of gears?
Chris

Sounds like you got a bad set of gears or they are not shimmed properly.Gears are NOT supposed to make noise.

Always go with PRECISION gears.Always top quality.