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Gear Brand

1675 Views 26 Replies 10 Participants Last post by  BDZ71
Like the title says. Im going to put 4:56 in as soon as I can but what are some of the gear brands I need to look at and ones I need to stay away from?

I want something that will last and is of good quality but I really dont want to pay 2 times as much if there is something else that is just as good.

Randys' R+P seems to push Yukon Gears. Are those any good?

Also. what should I do about a Rear Locker/LSD?
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I run the Yukon Brand in my truck and have installed many sets on other trucks from Yukon. I highly recommend them.

If you are going to do the gear upgrade yourself I would avoid the "Sierra Gear" brand. I have installed 4 sets ranging from 3.73-4.88 and each has had detrimental problems.

I would also avoid GM Gears on NBS vehicles. GM no longer uses Motive Gear for the new 7.625" and 8.625" gear sets. They switched to a new company I can't spell or say. It sounds like OlSan or OlKan. Something like that. Anyway, the pitch of the gear teeth are different on these gear sets to make them quieter. The bad part is backlash must be EXTREMELY "TIGHT" and the pinion depth pattern will not come out correct.

IMO any 8.5" gear set other than GM (NBS Only) or Sierra Gear is fine.

I run and Eaton Posi LSD. You can modify them so they are so tight they work "similar" to a locker. I chose this differential because I use big 37" Swampers and drive 97% of the time on the street. A Locker in a mainly street driven vehicle will place a high load on the carrier itself and could cause it to crack. The clutches (Or cones if you use an Auburn) of an LSD allow just enough slip to prevent damage and just enough traction to satisfy almost every need.

However, there is nothing like a Detroit Locker. Chose a Locker when off-roading is in your blood or if you don't want to give any excuses was to why you got stuck. When off-road you never know what you may come too and an LSD *could* let you down where as a Locker will almost guarantee dual rear wheel tire spinning.

I am a cautious driver off-road and my LSD has never let me down, but I can usually predict when it would.
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Precision gears are often considered the best. They arnt 2x as much, they are a little more but not much. By a little heres an example, the geniune for my d60 was 175, yukon like 190, precision was 225. Not much more.

About Yukon gear. Yukon gear does NOT manufactor their own gears, they buy other gears and repackage them. You can get very good gears this way, or some people say they have gotton shitty gears. Most people win in the gamble, some loose. Thats why I didnt use Yukon. I am however using Yukon 4340 axle shafts so go figure.

If you want a LSD both the eaton and auburn are very good units. Ive driven a truck with the auburn, and I was actually impressed.

Now with that said I think you should save your cash and ill help ya build a 6 lug 14ff with a detroit :rocking:
Thanks for the info Vhato :head:

Dark Eternal said:
...Now with that said I think you should save your cash and ill help ya build a 6 lug 14ff with a detroit :rocking:
If I can find a 14SF or FF in good condition for a good price that is the plan. If not Ill have to stay with the 10Bolt. Im looking :D
4 wheel parts uses genuine gear...they put 4.88 in my lifted silver truck and it has been bashed in the dunes many times and havn't had one problem
Here's my other ride

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So is the Auburn Pro a Clutch type Diff where it will wear out? How about the Eaton?

Is the Powertrax No Slip a LSD or a Locker? Does anybody have any info on these? I was reading about it and they have a vid on there site that looks like the Powertrax No Slip does a good job of traction.

Another option would be a selectable locker. Are there any of these that are good. A Electric one. So it could be open untill I hit the dirt, or need it and flip a switch. When they are locked are they just like a Detroit?

I want to lock this thing so bad with a detroit. But I just think the 10Bolt will wave ByeBye if I lock it with a detroit with these tires.

Thanks for your help. I hate trying to make up my mind.
The Auburn Pro is a "cone" type. I assume the cone's wear out like anything else (I don't know though). The Eaton Posi is an LSD with Carbon Fiber clutch packs. It is doubtful you would wear them out. But I wrote a tech article on how to modify them anyway.

The PowerTrax is nice. Only problem is it lacks spider gears so the "differential" isn't there. If you tow a trailer there are going to be many situations where the PowerTrax will "lock up" causing excessive tire wear.
The next problem with the PowerTrax is it's an Insertable locker. To you that means it won't fit in place of your exisiting spider gears. You must have an 8.5" Open Carrier so you can remove the spider gears and insert the PowerTrax unit. The 8.625" Open Carrier on NBS Trucks will not allow for an Insertable Locker. So you gotta find an OBS donor carrier. IMO, more trouble than they are worth.

Electronic Lockers are the best of both worlds. Only downside is drilling a few holes and some electrical connections.

The Detroit is a device that you Install and go about your business. It will remind you it is there sometimes, but that is no big deal because it lets you know it is working.

You sound like a guy who doesn't like excuses. If you install the Detroit you won't be asking yourself why you installed the LSD when you get stuck in the mud. With a Detroit Locker the only reason you will get stuck is because your frame bottomed out on the mud.

The 10-bolt axle isn't bad.

Big Mudders+Detroit Locker+Mud Pit+4.56 gears or more=Broken gear teeth.

Big Mudders+Detroit Locker+Mud Pit+4.10 gears or less=Bent axle housing (Weld in an over axle truss) and/or snapped axle shafts and/or crushed c-clips.
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Ive seen that most of the time the c clips will give way before the shaft on a 10 bolt twists, I have even seen the carrier spinter before the shafts broke.
I have 4.56 Ginuine Gears in mine and so far so good! They took awile to break in but now they are performing nicely.
There is a semi float for sale on pirate, Its out of a 2k2 or 2k1, only prob is that even those a 8 lug.
Soaking up the info :head:

DE, Vhato, and whoever might know. If I find a GOOD SF14Bolt and it is DiskBrakes but 8lug. How hard is it to convert to 6lug so I can keep these wheels? And how much will that cost?
put it this way, it would be cheaper to convert a 14 ff to 6 lug, which makes having the sf pointless.
BDz71- i have a ff14b i will sell you, 4.10 gears that way you dont have to switch carriers when you go to a low gear.
umm, you dont gatta switch carriers anyways on a 14 bolt :read:
from 4.10 down i thought you did? i read that somewhere musta been msitaken.

DE- if you come across any 4.56 or 4.88 gears for a ff14 thats a decent deal, gimme a shout!
Ill let ya know if I do, Ive got a few people who might want me to do some work on their 14 bolts or build them one so if I get some leftover 4.56s or 4.88s ill hold them for you.
Dark Eternal said:
Ill let ya know if I do, Ive got a few people who might want me to do some work on their 14 bolts or build them one so if I get some leftover 4.56s or 4.88s ill hold them for you.
Dark Eternal said:
put it this way, it would be cheaper to convert a 14 ff to 6 lug, which makes having the sf pointless.
Why is that? Wouldnt you be basically doing the same thing if it was a SF or a FF? so why would the FF be cheaper?
I thought you would just need to change the axle shafts on the SF?
no because the NBS semi floats have different length shafts or something, I dont remember. Plus the rotors and shit like that wont work then and it gets very complicated. Its much simpler to just buy some 6 lug hubs for the 14 bolt. I saw a guy who converted a NBS 14 bolt semi floater to 6 lug and it cost him like 1000+
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