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Discussion Starter #1
So I have 38/15.50/18 and I do almost all highway driving in the middle of nowhere. So what gears do you recommend? In 1 1/2 to 2 years when the 38's are shot I will be going done to 35's so I don't really want to have to change the gears again. I was thinkin of going with 4.56's? Yes I know they are not ideal for 38's but it will be better then the 3.42's. it will work great for the 35's. Opinons?
 

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Pat McCrotch
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If you are going back to 35s then go 4.56's especially with highway driving. 4.88s would be great for now but suck for 35s and highway driving. I think you already had the right answer on your own. I run 4.88s with my 37s and its a bit shorter than stock and when doing 75-80mph I often wish I had a lower numerical gear ratio. 4.56s and would be great now compared to you 3.42s and great with 35s.
 

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Registered
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I run 4.88's with 35's right now and I'm flat out spoiled! The power is great. Plus I'm not turning that many rpms on the highway. At 65 mph I'm turning about 2100-2200 rpms. I checked my mileage last tank and I got about 13.5 mpg. Not too bad considering with 3.73's the week before the gear swap I got 14.2 mpg. The .7 loss in mileage is well worth the power IMO.
 

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NCOR
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8,449 Posts
1/2 ton or 3/4-1 ton? Makes a difference IMO.

1/2 ton a 4.88 set would be fine as your OD is pretty high numerically.

The 3/4-1 ton would benefit from the 4.56's in OD, but starts are still going to be kind of slow with the tall 1st. I have 4.88's with 38's and it doesn't get up very quickly at all with the 80e.
 

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Discussion Starter #6
its a half ton 10bolt :bawl: so i'm getting 4.56's what kind do you reccomend and where should i order them from on the net?
 

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The suspension changer
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I don't know if your is 4x4 or not but I have a brand new set of 4.56 front gears still in the box for sale.
 

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Discussion Starter #8
yes its a 4x4. what kind are they? do you have them for the front diff also? how much do you want for them? what did u pay?
 

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The suspension changer
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I have the brand new in the box for the front diff. They are genuine brand. I don't really know exactly what I paid because I bought everything from steven at one time. I would sell them for $80 for the front set. The rear I currently have in my truck right now but I will selll them if needed because I am going to 5.13s instead of the 4.56s. If you can get me some 5.13s I will trade you or something.
 

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Discussion Starter #10
I really know nothing about qaulity and pricing of gears. Can someone help me? I'm assumining you can mix brands of gears between the front and bac.. I thought gears ran around $600 or so? Educate me please.
 

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The suspension changer
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Genuine is not the best I'm sure but its what I had with the deal. I know like yukon are one of the best ya know. Usually gears run around 120 ish to 180 a set or so. Correct me if I am wrong though.
 

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Discussion Starter #12
So usually its the labor that adds up than? So if i bought the front from you I could put a different brand of gear in the back or is that not recomended? Or is it cheaper to buy the front and back together?
 

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The suspension changer
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You can run different brands with no problems. You just have to make sure its the same ratio front and rear. I am not sure about it being cheaper buying a set front and rear though. I would think it would be the same as buying them seperate. Only reason I am trying to sell them is because I know for sure I am going to 5.13s so why waist time installing them when they are coming right back out.
 

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The suspension changer
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I am not sure those are the right ones.... Someone chime in lol.. I have 4.56s and 38 ant at 65 I am at like 2100 rpms or somewhere in there.
 

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Registered
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So I have 38/15.50/18 and I do almost all highway driving in the middle of nowhere. So what gears do you recommend? In 1 1/2 to 2 years when the 38's are shot I will be going done to 35's so I don't really want to have to change the gears again. I was thinkin of going with 4.56's? Yes I know they are not ideal for 38's but it will be better then the 3.42's. it will work great for the 35's. Opinons?
31/3:42
33/3:73
35/4:11
37/4:56

to keep your speedo close.

Go for the $300-500 14 bolt swap you can find up to 4:10's in a stock 6 lug 14 bolt pretty much anywhere.. just bring it to someone to check it out/go through it before you install it. http://www.car-part.com try to search by the same year as your truck that way you have the stock shit to put right back in... I found that its cheaper to swap the front diff and rear to a 14 bolt than most guys would charge to do it correctly out here.
 

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Watchu know about trucks?
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I kinda have a question to go along with this. I'm getting 35's here pretty soon and will ned a gear swap. The only thing is, when I search for stuff its not vehicle specific. I have a 2001 Suburban 2WD. I see references to number of bolts and gear diameter (I assume). What do I have?

I come from working on FWD lowered vehicles, this is my first "truck". And I've only done a body lift on a Jeep YJ in the past.
 

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Cartmans Critters
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8,867 Posts
If you are going back to 35s then go 4.56's especially with highway driving. 4.88s would be great for now but suck for 35s and highway driving. I think you already had the right answer on your own. I run 4.88s with my 37s and its a bit shorter than stock and when doing 75-80mph I often wish I had a lower numerical gear ratio. 4.56s and would be great now compared to you 3.42s and great with 35s.
Listen to Rich hes got it......Theres no other way to go either 4.56s or 4.88s.

Hell read past threads, read my gear thread, 35+ go 4.88s
 
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