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Discussion Starter #1
Hey everyone, I just ordered my gears through "Dark Eternal" and his shop in Texas. He has great prices! Call him if you want some! Oh and I actually ended up going with 5.13's for my truck. I figured why not? For trailers and crawling and such. I will never really go faster than 75 on the interstate anyways.. and 70 is about average for me. People say that they are weaker... but, i dunno.. Stephen (Dark Eternal) was saying how they are probably 1-2 % weaker than 4.88's ... so I guess if there gonna break.... than there gonna break! I also ordered a true trac for my rear. Tell me what yall think!
 

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GMFS slowest truck :read:
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yeah, once you get over 4.11s, everythings gonna be weaker. 5.13s and 4.88s are damn near the same weakness...BTW, good choice on the ratio.
 

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HOT AIR BALLOON OWNER
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Good thinking on the 5.13:1
 

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Discussion Starter #7
you're going to love having low end torque but passing cars on the highway won't be fun.
Yeah I dont get it.... I dont see how that would make much sense. :think: Also, I wont be passing too many people anyways, like I said I stick the cruise on about 65-70 for mpg purposes...
 

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You'll be happy. My old truck was still lagging in acceleration, with 36s/4.88s. When I had 35's, 4.88s seems to be perfect. 37s/5.13s will be a great combo and it'll put your engine back into a usable powerband. Highway RPMs will be high (probably around 2350-2400) at 75mph, but not horrible.

With 4.88s and 36's I was just a hair under 2300 RPMs going 70mph.
 

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bullshit it wont.

higher RPMs = deeper into powerband. Until you have run it, you have no clue.
I have 4.56s on a 33.4" tire. Maybe not as deep, but certainly similar. I love it around town but feel like I had more power at high speeds when I had 3.42s and 30" tires.
 

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Discussion Starter #10
Thats most likely because your higher now and pushing more air, and the tires are heavier... all that stuff slows you down.
 

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GMFS slowest truck :read:
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I have 4.56s on a 33.4" tire. Maybe not as deep, but certainly similar. I love it around town but feel like I had more power at high speeds when I had 3.42s and 30" tires.
you do realize that rolling mass is your enemy? THAT was YOUR problem. Go check the GMFS fastest truck chart and take a look at my times/speeds. on 40s, my truck wasn't terrible until it got to speed. 1/8th mile time was respectable, 1/4 wasn't, and i attribute that to 125 lbs spinning at each corner. it takes A LOT to get heavier tires moving.

Yeah I dont get it.... I dont see how that would make much sense. :think: Also, I wont be passing too many people anyways, like I said I stick the cruise on about 65-70 for mpg purposes...
and im glad to see someone else realizes that lifted trucks aren't built for speed. 65ish is gonna be about the best spot for a properly geared lifted truck. It gets teh RPMs up enough to keep it in the powerband and is still slow enough where air resistance isnt KILLING it...
 

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Bayou Surface Drive, LLC
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Bad Bowtie i did some cals for you. You got 37's and you factor in tire suat and wear they will roughly be 35.5" tall IMO (just for cal purposes i'm only assuming here)
With 35.5" tall tires and 5.13 gears here is rpms at speeds on a 4l60e
Speed 3rd gear RPMS OD RPM'S
55 2672 1871
65 3158 2211
70 3401 2381
That will be Fun Im going deep in my toyota. I kept it to 4.56 on my z , but it was fun with my short 35's lol they were 32.75" i was 2300 at 70 in OD
 

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Discussion Starter #14
Cool thanks man, yeah 2200 to 2300 doesnt sound too bad, and it will be better for trailers on hills and stuff.... It will keep the tranny cooler too... if my logic is right...
 

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GMFS slowest truck :read:
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Cool thanks man, yeah 2200 to 2300 doesnt sound too bad, and it will be better for trailers on hills and stuff.... It will keep the tranny cooler too... if my logic is right...
it will keep it cooler. less strain on everything all around...and better mileage to boot:rocking: :rocking:
 

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i wish i would have known that i was gonna get 37s when i bought my gears, sure as hell wouldnt have gotten 4.56s, but o well, as long as i keep it above 65 mph on the highway, it still takes quite a hill to make the tq lock up. when im at 55 or 60 though, its quite a different story, low rpms and it always seems like it cant get comfortable. good choice
 

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Bayou Surface Drive, LLC
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You mean un lock on hills.... when the tcd is unlocked its slipping and creating heat. when locked, its not slipping
 

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yea, youre right, i always get that shit confused, thanks broman
 

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I still can't decide what gears I want (sorry to steal the thread). I have 35's on my 05 z71 and cant decide between 4.56 and 4.88. I don't see myself ever going over 37's and will most likely max out at 36's. It's my daily driver and I dont take it offroadiing too much. I want to have good towing capabilities and save my tranny. What are the advantages and disadvantages of each (with gas mileage suggestions also)?

I'm also getting the detriot tru-trac.

Thanks
 

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Discussion Starter #20
I would say definitely 4.88's... ecspacially for towing... and the 36's and maybe 37's someday.
 
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