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Wanted ISO 12 Bolt 6 Lug rear differential
- Thread starter FatBoyM
- Start date
any particular gear ratio?
Because everyone is speak too/ read say the 10 bolt is weak & 12 bolt will just bolt in. Since mine has some metal shavings in it with 4.56 gears I'm just going to upgrade.
Is the 10-bolt weak? Of course, but it's all relative. Is a 12-bolt an upgrade? No.
10/12 bolt is about even across the board for strength . if you want 6 lug upgrade you need 9.5 semi float 14 bolt and weld on new perches and shock mounts .
The truck currently has a 10 bolt/ 6 lug that needs to be addressed.
I do not know the difference between the 2. I was told if I'm going to rebuild the rear diff I should upgrade to a 12 bolt because it will drop in easily.
I know the 14 bolt is awesome, but that's overkill for a daily driver with occasional light offroading.
I don't have the skills to do the work myself, so I've gotta do what's affordable for me.
I do not know the difference between the 2. I was told if I'm going to rebuild the rear diff I should upgrade to a 12 bolt because it will drop in easily.
I know the 14 bolt is awesome, but that's overkill for a daily driver with occasional light offroading.
I don't have the skills to do the work myself, so I've gotta do what's affordable for me.
Like i said and others . Side by side the parts are no stronger in a major upgrade level from 10 bolt to 12 bolt . Fix your 10 bolt or find a 10 or 12 bolt with good gears in it you need to match .
But dont be hunting for just the 12 bolt . . . And for more fun on 12 bolt dont get mixed up with car 12 bolt parts . There is car & truck 12 bolt .
But dont be hunting for just the 12 bolt . . . And for more fun on 12 bolt dont get mixed up with car 12 bolt parts . There is car & truck 12 bolt .
That's true, but it's also true for the 10-bolt. 5-lug vs. 6-lug is usually enough to differentiate.
The advantage to the 10-bolt is there are way more of them out there, so you have better odds to find a good one. There are few to none stock 4.56 1/2-ton rear ends, but many have been upgraded over the years. An option you should consider is tearing down your existing axle to see what's wrong and then rebuild it. If you just lost a bearing, the gearset may be fine and you'd be in the project just a couple of hundred dollars. The setup of the existing gears is pretty easy if you're just doing bearing and seal replacement. If it needs tons of parts, then you know for sure swapping it out is justified.
What kind of locker/LSD do you want? Now is the time to work that consideration in.
If you want an upgrade, but stay 6-lug, read up on the 9.5" swap.
Thank you for the detailed input.
The current diff is 4.56 on the stock 700R4 Transmission with a 353 blueprint motor. My concern is too much stress on the current differential & I'll be going through this again.
As far as "locker" IDK I'm assuming it's open.
I really appreciate all the input, I know very little about this stuff.
Yes this would be awesome but costly since I can't do the work myself.
What's the difference then, other than 1 is 10 & the other is 12?
I've spoken with a few people who know a lot about this & they say the 12 bolt is better & drops right in place vs upgrading to a floating or anything else really rugged.
This truck is a street/ light off road truck that will be driven, not a show queen..
What size tires will you run? Stock axles may be fine. "Light off-roading" is a term we hear a lot here, which essentially means "I'm going to dabble in off-road", so you'll try more until it breaks.
How many (real) stories do you have of broken 10-bolts and broken 12-bolts? You can break anything if you wheel hard enough. 100,000 miles is reasonable, how long will that take you? A non-maintaned, 40-year-old gov-lock differential that blows up isn't a great data point.
How many (real) stories do you have of broken 10-bolts and broken 12-bolts? You can break anything if you wheel hard enough. 100,000 miles is reasonable, how long will that take you? A non-maintaned, 40-year-old gov-lock differential that blows up isn't a great data point.
10 bolt has bigger stronger pinion gear bearing size . 12 bolt is smaller .
12 bolt is 8.8 ring gear 10 bolt is 8.5 .
12 bolt is 30 spline if i recall shafts and 10 bolt is mostly 28 spline until late 80's just before new 88-up body design .
There is pros and cons to both axles . Pick your poision and pic good parts . Its basicly 50/50 in the end for stronger .
I swapped in a 12bolt in my 2wd build only cause i got a super buddy deal and it had nice clean guts and 3.73 gears i was looking for . But i also would of been just fine if a 10 bolt was found .
12 bolt is 8.8 ring gear 10 bolt is 8.5 .
12 bolt is 30 spline if i recall shafts and 10 bolt is mostly 28 spline until late 80's just before new 88-up body design .
There is pros and cons to both axles . Pick your poision and pic good parts . Its basicly 50/50 in the end for stronger .
I swapped in a 12bolt in my 2wd build only cause i got a super buddy deal and it had nice clean guts and 3.73 gears i was looking for . But i also would of been just fine if a 10 bolt was found .
While I appreciate your knowledge & input, please don't take the "rookie" moniker to mean without experience in general.
I'm a "rookie" K5 owner with no experience "building" vehicles, but decades of driving them.
My off reading is reserved for my RZR4 & 1990 Toyota 4x4, sold the 1999 Silverado 4x4 for the family.
I don't rock crawl in this vehicle, mostly fire roads & some mountain trails, but I prefer to venture on my Street Glide.
I'm really looking for mechanical advice on this (new to me) vehicle that I plan to remove the top, fire up a cigar, crank the tunes & head out to the gun range, river or mountains for the views. I've got nothing to prove "off roading" more than some light off roading.
The vehicle has a 35 inch mudders which I would gladly put some a/t wheels on instead but these are brand new so I'll ride them out..
Back to the OP....
I have no knowledge of the 10 vs the 12, relying on this great forum, friends, random mechanics that I'm interviewing to handle the job.
There's a lot of opinions, so if you've got info to help me get to where I'm trying to go, then thank you.
Sounds like I should have the 10 bolt inspected deeper & plan rebuilt gears.
Great post thanks. I think I'm leaning towards rebuilding the 10 bolt & calling it a day.
I have a couple other items: cross over steering & ORD leaf springs to tackle as well as frame reinforcement in some key areas.
Advice on "good" parts (gears) for the rebuild, should I do the axels or any thing else?
This way I can direct the mechanic without being over sold crap.
No offense intended. Some would say 35s on a s/f 10-bolt is pushing your luck, but as you say, driving style makes a big difference.
i got a friend who use to tuff truck thrash his short bed on 3.08 open 10 bolts . he was spinnin 38" tsl swampers and blew up a lot of motors and few th350 trans . never popped a axle .
No offense taken, just wanted to clear the term "rookie".
I really appreciate the knowledge here from you & others, because yes I'm ignorant to the mechanic repairs.
I was hoping to do the repair/upgrade once. I've been told to 12 bolt is an upgrade & simple drop in.
I'm hearing conflicting opinions here.
If the 12 bolt is not worth the "upgrade", then I should just rebuild the gears in the 10 bolt.
The axel didn't fail the gears did maybe I just need better 4.56 gears (idk what's in there) I bought it with the current gears.
I really appreciate the knowledge here from you & others, because yes I'm ignorant to the mechanic repairs.
I was hoping to do the repair/upgrade once. I've been told to 12 bolt is an upgrade & simple drop in.
I'm hearing conflicting opinions here.
If the 12 bolt is not worth the "upgrade", then I should just rebuild the gears in the 10 bolt.
The axel didn't fail the gears did maybe I just need better 4.56 gears (idk what's in there) I bought it with the current gears.
