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Discussion Starter #1
Some of you may know that I plan on squeezing 38s on my truck after I put the lift on. I will be doing the gears when I do the lift and would like to know what would be better, 4.56 or 4.88? I will also probably buy a auburn lsd. I plan on buying gears in 2 weeks, but my friend just informed me that he has a 14bolt full floater that he wants to get rid of, just has a blown posi. Would it be worth it to use the 14 bolt instead of my 10? I would need to upgrade it to disc brakes and 6 lug, is that hard and expensive to do? or would I be better off just regearing my 10 bolt? Thanks
 

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If you are going to stick to the street. The 10Bolt should be fine IMO. If it breaks fix it.

But only you know how you will use your truck. 38's are a good size tire and if you are planning on wheelin it it might save you more money in the long run to swap in the stronger axel.
Hard call, only you can make lol.

Actually Im trying to figure out the same. Cant decide if I want to regear this one and hope it never breaks or go find me a 14Bolt SF 6lug (or convert it) and gear/lock that to put in. :insane:
 

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Go with 4.88s...that lil bit lower gearing will be very nice with 38s.
 

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4.88s are probably the better choice but don't always mix well with 10-bolts. Problem is the lower gear you choose the less teeth on the ring and pinion which makes it easier to strip the gears. Me personally, I wouldn't attempt 38s on a 1/2 ton. I would even be cautious putting them on a 3/4 ton. IMO your better off with a nice set of 35s or 36s and some 4.56s.
 

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y2kboti said:
4.88s are probably the better choice but don't always mix well with 10-bolts. Problem is the lower gear you choose the less teeth on the ring and pinion which makes it easier to strip the gears. Me personally, I wouldn't attempt 38s on a 1/2 ton. I would even be cautious putting them on a 3/4 ton. IMO your better off with a nice set of 35s or 36s and some 4.56s.
honestly, if its street driven and you are pretty easy on it, the ten bolt rear shouldn't have much problem...if you play hard on it every once in a while, its not hard to break a 10 bolt with 38s, but people do run them...if you wanna play with the truck, 10 bolt is not your answer...but then again, half ton IFS with 38s is not a good idea either...again, like y2kboti said, 4.88 gears have smaller teeth and everything, and can stip them easier. if you are easy on it, again, you should have no worries. i wouldn't really wanna run anything bigger than 35s on half ton IFS, but i guess if its gonna be a street queen, thats not too big of a deal...but im just to hard on my stuff for it to last long...
 

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Drive It Like Ya Stole It
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Just some details on how to convert a 14 bolt to how you need it.

1) disc conversion. You need the brackets, you can eiterh fab them yourself if you have the tools (not hard) or buy a set for $75 or less. Next you need the rotors, get k20 front rotors, cost you maybe $100 max for 2 new ones. Then if you dont care about a parking brake you can get k20 front claipers as well, but if you DO want a parkiong brake you need cadilac eldorado calipers from like an 84 or so. All of the part #s are on my SFA page if you are interested. All in all disc brake conversion runs 300ish.

2) Gears and locker - just like any other axle you will have to gear and lock it. A detroit is very cheap for these axles, and there are otehr options available also. Gears go as low as 5.13

3) 6 lug - 2 ways to go about it. The crappy unsafe way I wouldnt do which is spacers, I wont even talk about these more. Then the right way, 6 lug hubs. www.gradysoffroad.com sells them for about $265 each and they are a direct bolt in.

Now since your doing all of this I would go ahead and replacing all teh bearings and seals while your at it, which will run you $100+ also.



In other words its not a cheap option. Especially if you count labor in.

I also think its very dumb to run 38s on a half ton if you plan on doing ANY offroad in it.
 

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in the long run it will be better to invest the $ and use the 14bolt with 4.56's if you are going to have to drive the truck to work monday morning.
If it is just a show truck- 4.56's with the 10bolt
If you do ALOT of offroading..5.13's with the 14 bolt
 

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Discussion Starter #9
Thanks for the help. I know that 38s on a 1/2 ton isn't a good idea, but you got to pay to play, and the only offroading I will be doing is on the beach maybe 4-5 times a year. I thought that converting the 14 bolt to work wouldn't be cheap and I was right. I think I will end up using 4.88s in my 10 bolt.

For those of you that have done gears in the ifs diff., is it alot harder to do? I plan on doing it while doing the lift install, so it will be damn near apart. Does it take more know how then doing a rear?
 

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Be careful,
I roll 4.56's and 37's. My truck is a "STREET QUEEN" and this happened.




The front is WAY easier to do because you can do it on a bench. The main difference is putting in the shims for backlash in the rear is less than satisfying whereas setting backlash in the front requires no shims at all. You turn spanners. Real simple, just be careful not to break the clips in the front that hold the spanners in place. I would rather do front diff than a rear any day.
 

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Drive It Like Ya Stole It
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do you know how to set up gears? If not its probvably not something to atempt without someone who knows how. You need a press, dial meter and a good amount of know how.
 
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