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Discussion Starter · #1 ·
Alright guys here is my dilema. I have an 05 Crewcab 1500 Z71 with the 5.3 in it with a 6" fabtech lift and 35" KM2's. I am looking for the correct gears for the truck. hard to do since im in the desert. it has IFS up front. What size is the IFS and rear housing? ive been reading alot on the yukons and motives and need some help chosing between 4.56 and 4.88 gears. i tow a 24' enclosed race trailer on the weekends and it kills it right now. and what is ur guys' best opinion on gear size. thanks for the help. im hopin the rear has never been swapped. help on rear and IFS size and gear choice please. thanks guys. Chris
 

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dunemashingismyspieclty
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id go with 4.88 if i tow 25%+ of the time....4.56 are fine will give you a better MPG ,lower revs
 

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I have posted on several other gear threads and nobody has said anything yet. Sorry to jack your thread!

Which gears should i get for my truck? 6" on 35/12.50/20's with 3.73's. I might even make a few passes on the strip for fun, but i do haul a lawnmower trailer every weekend and just with that it is a dog.
 

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i wouldnt really worry about the ifs so much as the 10 bolt out back since your towing pretty regularly but i would go 4.56 to save you on the week days and still help you on the weekends
 

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I don't have a truck
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4.88:1, that's the only way to go.

Your mechanical advantage will increase and towing power will as well. Forget the 4.56:1 with that big of a tire.
 

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i'd say at least 4.88's with larger tranny cooler and tranny temp gauge to keep a eye on things...
 

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Discussion Starter · #8 ·
ok so what size do you guys think the front ifs is and the reat. heard something like 8.25 and 8.6 or 8.8 something like that
 

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GMFS Military Member
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8.6 rear and 8.25 front. Go with 4.88 Yukons and Detroit true trac.
 

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Swamper Brotherhood
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4.88
 

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Discussion Starter · #13 ·
i have a soft cover from extang on there. throw too much stuff in the rear to have a hard one on there. thanks for the help on the gears guys
 

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Discussion Starter · #15 ·
ok every site ive been on for gears is telling me i should have a ten bolt with disk brakes on my 05 z71. i have drums on there, so unless my rear was changed what rear gears do i order. i saw the front IFS at 8.25 so up next is the rear. thanks for any inputs and the help guys.
 

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Where's the van?!?!?!
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05 has drums, ignore the brakes... the carrier is the same. You have a 10-bolt 8.6" rear

Edit: and yes, 4.88s for both of you.
 

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Discussion Starter · #17 ·
ok guys. Motive or Yukon? and do i absolutely need a new locker in the rear or not? i really dont take the truck off road but when i take the dirtbike out and i hardly ever go muddin.
 

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GMFS Military Member
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Can't go wrong with yukons. I would go 4.88's, just get rid of the g80 if nothing else.
 

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Discussion Starter · #19 ·
so ill just have to buy a tuner also just to change the settings for the tires and gears too right?
 
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