Alternative to Ford Racing Ring and Pinion Gears for 8.8 IRS? What do you guys run?

specizripn

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Background:
So long story short the other day I got really bad wheel hop and made a nice sized hole in my rear diff cover. It was late at night so I drove the car (without gear oil :bash:) around 7 minutes to a friends house where I left the car overnight. The next day I had the car towed to my house, and after inspection the half shafts and suspension appear to be fine. Anyway my gears were whining before I blew the diff cover, and after driving several miles without gear fluid I'm sure my bearings, differential, and ring and pinion gears aren't too happy with me. So I have decided to overhaul the rear end. I'm going to buy a new Traction LOK because it isn't much more expensive than rebuilding my factory differential, so I may as well start from scratch. I will be getting one of the install kits with all new bearings, shims and seals from Ford Racing. Also I wan't to eventually upgrade to a Kenne Bell so I have decided to switch to 3.27 gears while I'm redoing the rear end. I will also be swapping out my bushings when I get the time, because I can't break anything else with wheel hop.

Question:
So after searching and scrolling through thread after thread I have found a lot of people on this forum advise against the Ford Racing/Motive ring and pinion gears. I can't seem to find any other brand of gears that specify their compatibility with the 03-04 cobra IRS. Are US Gear's 3.27 ring and pinion sets or another US manufacturer's gears compatible with the IRS or are they like the Ford Racing solid axle gears where the spider gears don't have the clearance machined for the C clips on IRS cars? I really just want quiet sturdy gears that I won't have to mess with again. I can't tell you how annoying the growling got on a highway cruise or something. I really want gears that can handle a big PD blower and built motor if I chose to go that route, but are also quiet. Does anyone have any recommendations? I also plan on having the gears REM polished, regardless of where I get them from.
Any advice would be great! Thanks! :rolling:
 
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2003cobra22

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If your replacing the carrier I advise going with the Eaton Truetac over the Traction loc no clutches to wear out just replaced one in my 2007 GT rear end
 

specizripn

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If your replacing the carrier I advise going with the Eaton Truetac over the Traction loc no clutches to wear out just replaced one in my 2007 GT rear end

Thanks. After further research I think I'm going to go with the Truetrac. Now I just have to figure out which manufacturer of gears to go with.
 
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Rich'sTRsvt

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3.27 is what 99/01 cobras came with from the factory. Edit; Just so you know the irs diff will fit any 8.8 ring and pinion.
 
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2003cobra22

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Thanks. After further research I think I'm going to go with the Truetrac. Now I just have to figure out which manufacturer of gears to go with.
Good choice I also replaced the 4.56 with Ford Racing 3.73 ring and pinion no issue yet
 

96gt02

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You could go with the weir low friction gear kit, ive heard great things but pricey.
 

hotcobra03

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I tried 327s..car idled at 80mph...for a daily driver car we didnt like them..

but I can understand to help tire spin..but the added torque might break more than expected
 

specizripn

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I may consider just going with the stock 3.55 gear ratio, i'm not sure. Hotcobra did you have 18" wheels or do you have the 0.50 6th gear ratio or something? Because when I use the trenenc gear ratio calculator it shows 74mph at 2000 rpm with the 3.27 ring and pinion ratio. Also I looked at the T2R, but I don't open track the car at all, so I don't know if I can justify spending the extra money on it. Ill also look into the weir low friction gears.
Thanks guys!
 
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