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Discussion Starter #1
Im looking into gears and i need to know how big my rear end is? i know its a 10 bolt but im not sure which spline or size?
And im guessing you gotta do the gears front AND back right?

Mines a 4.8L not a 5.3 if that makes a difference.
 

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Your rear is a 10 bolt, 30 spline, 8.625". It's the same rear as the 88-98 trucks, which was an 8.5", but in 99 they started using larger bearings on the differential, so they dubbed it the 8.625", or 8.6" for short.

The front I'm pretty sure is a 8.25" differential.

Go here and double check: http://www.ringpinion.com/
 

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Discussion Starter #3
Thanks a million man, I've looked everywhere on google and couldn't find nothin!!
 

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Discussion Starter #4
Oh and I was wondering, if you do a detroit locker and 4:56's do you only need it in the rear? Then just do the 4:56 gears in the front? Or do you need a detroit locker in front and back??
 

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Discussion Starter #5
Bumpp to the question above....and how much different is the Eaton Truetrac? I can only find posi tracs and lockers for the rear, there seems to be none for the front.
Do i need one for the front too? or just need one and gears for the rear and just gears for the front??
 

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Discussion Starter #6
I gotta bring this thread up again...im ordering my locker today so i need to confirm my rear end size.
Im pretty sure my rear end is 8.5"/30 spline/10 bolt since i do not have rear disc brakes....am i correct??
8.6 would have rear discs.
 

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Discussion Starter #9
oh i know im only getting one in the rear...
 

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hella cute n shit
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Don't get a locker, get a Detroit Truetrac.

And are you running 4.56's or 5.13's with those 37's?
 

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8.5 and 8.6 are the same thing. The only difference is your rear end uses larger bearings compared to the OBS trucks (pre-1999).

By the way, don't order from Ron's Machining Service. I had a bad experience with him.
 

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8.5 and 8.6 are the same thing. The only difference is your rear end uses larger bearings compared to the OBS trucks (pre-1999).

By the way, don't order from Ron's Machining Service. I had a bad experience with him.
I just ordered from Ron's and could not any happier. What went wrong with your order if you don't mind me asking??
 

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I just ordered from Ron's and could not any happier. What went wrong with your order if you don't mind me asking??
I received defective gears (they were cut wrong or something). I paid a shop to install them because you can't tell by looking at them if they're bad or not. Turns out they were. Ron sent new gears. I paid to install new gears. Ron wouldn't refund me the $350 I paid to install the defective gears that HE sold me. So I'm out of pocket 350 bucks.
 

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Discussion Starter #15
Don't get a locker, get a Detroit Truetrac.

And are you running 4.56's or 5.13's with those 37's?
Whats wrong with the full locker?
Im getting 5:13's for the 37's.

Im getting my stuff probably from 4wheelparts
 

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I received defective gears (they were cut wrong or something). I paid a shop to install them because you can't tell by looking at them if they're bad or not. Turns out they were. Ron sent new gears. I paid to install new gears. Ron wouldn't refund me the $350 I paid to install the defective gears that HE sold me. So I'm out of pocket 350 bucks.
Damn that sucks, I hope that shit don't happen to me because I have gears sitting here in the house waiting to be installed. If it does Ron's will be getting a phone call for sure.
 

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hella cute n shit
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Whats wrong with the full locker?
Im getting 5:13's for the 37's.

Im getting my stuff probably from 4wheelparts
It's not needed at all and will perform terribly on the street. A Detroit Truetrac will give you the reliable traction you want while still being very docile on the street when it comes to how it acts while turning and such.

Full locker is going to be hell on the streets and probably overkill for what you need.

Ive heard alot of bad things about 4wheelparts.
Yeah I definitely wouldn't go through 4wp, my friend has had shitty luck with them and I personally won't every buy from them. I buy my stuff locally but if you don't want to go through Ron's Machining you could order from Randy's Ring & Pinion.
 

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Discussion Starter #19
Yeah I definitely wouldn't go through 4wp, my friend has had shitty luck with them and I personally won't every buy from them. I buy my stuff locally but if you don't want to go through Ron's Machining you could order from Randy's Ring & Pinion.
Yeah i was going to go through Randys before. Thanks man...that helps. I didn't know a locker was that bad for the street.
But isnt the Trutrac basically just what i have now? my truck now has LSD instead of full posi.
How is the Yukon Duragrip?
 

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hella cute n shit
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Yeah i was going to go through Randys before. Thanks man...that helps. I didn't know a locker was that bad for the street.
But isnt the Trutrac basically just what i have now? my truck now has LSD instead of full posi.
How is the Yukon Duragrip?
Your truck has a G80. The Truetrac is a helical gear-driven limited slip. It has no clutches to wear out like a clutch-driven one.

I'd run that over a Duragrip any day. I have one in both of my trucks and have never had a single issue with either and they always perform just as I'd expect them to.
 
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