How common is it for a 4.10 gear installation to go bad? Bad meaning: whining, exploding, breaking down, etc. Does it happen often or have most of you had successful installations? If the chances of something going wrong are too high, i think i'd rather look into swapping the whole rear end to a 8.8 gt end, because of the guaranteed working condition and t-lok.
How common is it for a 4.10 gear installation to go bad? Bad meaning: whining, exploding, breaking down, etc. Does it happen often or have most of you had successful installations? If the chances of something going wrong are too high, i think i'd rather look into swapping the whole rear end to a 8.8 gt end, because of the guaranteed working condition and t-lok.
I would just get the rear end, its almost cheaper in the long run
__________________
2006 V6 Pony Package Premium -Mods: 61mm Powerhouse Turbo and Intercooler, Evolution Dyno Tune(Jon Lund), Steeda Performance Shorty Headers. Current Numbers: 350 rwhp/420 torque @ 8.3 psi (low boost)
415 rwhp/470 torque @12 psi Car died 6/23/09
New Set Up: 4.6 3v With Manual Trans, Bolt Ons
i got the 4.10 ring and pinion in mine, and no trouble so far, but if i had it to do over again i would have switched to the gt rear end, just because that would be easier to do myself and i don't like having anyone else working on my car. and alot can go wrong with gears. not that it is extremely common though.
__________________
Torch red 2007 4.0, in dash flip out Jensen touch screen dvd player, single Flowmaster American Thunder exhaust, Airaid CAI, 4.10 rear gears, Ford Racing T-lok, SCT XCal 3 tuner w a bama race tune, sequencial taillights. 2 Audiobahn 400w 12" subs w 2 pioneer amps, glowshift gauges, Pioneer navigation system, Shaftmasters 4" aluminum drive shaft, Zex wet nitrous kit 75 shot, with window switch, and dual outlet purge kit, hollowed out catalytic converters.
Seriously bro....save the money and buy a gt takeoff 8.8 rear end with 4.10s. I bought all the supplies for a gear ratio switch with a bearing kit and gear oil, but it was installed completely wrong. Just buy the take off and be done with it. Because one bad install will end being the same price as a takeoff rear end.
__________________
2006 4.0L V6 Mustang- Pony Package, Shelby GT500 Spoiler, JLT CAI, SCT X3 Tuner, 93 Octane Tune, Magnaflow Catback Exhaust, Bosch Iridium Spark Plugs, Firestone Firehawk GT Tires, 8.8 GT Rear Axle, Ford Racing 4.10 gears, Ford Racing Trac-Loc, Amsoil Synthetic Motor Oil 5w-30, Amsoil Synthetic Severe Gear Oil 75w-90 w/ Friction Modifier, Powerslot Rotors, Hawk Performance Brake Pads, Fog & Headlight HIDs.
have your 4.10 gears broken down?? 
