Rear end swap 8.6" -> 9.5" for 35" tires

[randomsubfan]

Hi there!
Now I'm going with 33" tires and no locker on rear end. Thinkin about 35" and ARB air locker.
Am I need to swap rear 10-bolt (8.6") axle to more reliable 14-bolt (9.5") axle for this?
I think the 8.6" differential is weak and it can lead to some problems with locker and 35". Am I right?

Maybe 8.6" is weak only with original GM differential and I can strengthen the 10-bolt axle by ARB locker diff or OX locker diff. Who knows?

 

[Marky Dissod]

... going with 33" tires and no locker on rear end. Thinkin 35" and ARB air locker.
Do I need to swap rear 10-bolt (8.6") axle to more reliable 14-bolt (9.5") axle for this?

Don't know if a 12-bolt would be easier to find? 14-bolt won't hurt, for sure.

I think the 8.6" differential is weak and it can lead to some problems with locker and 35". Am I right?

Pretty much yes, especially under a Suburban, especially with 35' tires.

Maybe 8.6" is weak only with original GM differential and I can strengthen the 10-bolt axle by ARB locker diff or OX locker diff. Who knows?

Don't know if the 8.6" is worth upgrading under a Suburban, think a bigger axle would be better.
4.30 or 4.56 axle gears though; 35' tires make axle gearing weaker, so you gotta compensate.

 

[justirv]

Hi there!
Now I'm going with 33" tires and no locker on rear end. Thinkin about 35" and ARB air locker.
Am I need to swap rear 10-bolt (8.6") axle to more reliable 14-bolt (9.5") axle for this?
I think the 8.6" differential is weak and it can lead to some problems with locker and 35". Am I right?

Maybe 8.6" is weak only with original GM differential and I can strengthen the 10-bolt axle by ARB locker diff or OX locker diff. Who knows?

I am starting the process on my '02 Tahoe Z71 (G80/GT4). I was able to procure a 9.5" 14 bolt, AXN 6-stud axle out of a 2012 2WD Eskie. Picked up a Yukon R&P in 4.10 and master build kit. Add to that an Eaton TruTrack.
I'm one of those who plans on swapping out to a 9.25" IFS with an ARB locker. A 14 bolt should be able to handle 37's with appropriate gearing.

 

[swathdiver]

Hi there!
Now I'm going with 33" tires and no locker on rear end. Thinkin about 35" and ARB air locker.
Am I need to swap rear 10-bolt (8.6") axle to more reliable 14-bolt (9.5") axle for this?
I think the 8.6" differential is weak and it can lead to some problems with locker and 35". Am I right?

Maybe 8.6" is weak only with original GM differential and I can strengthen the 10-bolt axle by ARB locker diff or OX locker diff. Who knows?

An Eaton Trutrac can be put in either the 8.6 or 9.5 differentials. The Trutrac in an 8.6 is plenty strong for 35s unless you plan on racing the truck. Mostly street with occasional off-roading, no problem.

All of my trucks have 9.5s in them.

 

[randomsubfan]

Don't know if a 12-bolt would be easier to find? 14-bolt won't hurt, for sure.

Its not a problem to find I already have a perfect 6-nuts Escalade 2WD axle.
I hesitate couse its such heavy and big. I will lose some clearance. And there are only ARB selectable locker for 14-bolt. While for the 10-bolt axle I can find an OX selectable locker. OX is better then ARB.

I was able to procure a 9.5" 14 bolt, AXN 6-stud axle out of a 2012 2WD Eskie.

Yes, this axle

I'm one of those who plans on swapping out to a 9.25" IFS with an ARB locker.

Ahah me too! If I swap rear 14-bolt, I'll swap front 9.25" and will put an ARB in it. Full locked truck is a mud king

The Trutrac in an 8.6 is plenty strong for 35s unless you plan on racing the truck. Mostly street with occasional off-roading, no problem.

Dont wanna TrueTrac, but ist a good point. I suppose the OX locker is as strong as TrueTrac. Thanks.

 

[swathdiver]

Dont wanna TrueTrac, but ist a good point. I suppose the OX locker is as strong as TrueTrac. Thanks.

How do you plan to use the truck, mudding?

 

[randomsubfan]

How do you plan to use the truck, mudding?

Mostly street with occasional off-roading, as you said. Sometimes overlanding expeditions with light offroad.

 

[swathdiver]

Mostly street with occasional off-roading, as you said. Sometimes overlanding expeditions with light offroad.

Well, since you're running a 5-speed and are customizing the truck, why not go with the 9.5"? I would. As for the lockers, the G80 works for me and I don't have experience with the others other than what I read on these here forums.

 

[justirv]

Its not a problem to find I already have a perfect 6-nuts Escalade 2WD axle.
I hesitate couse its such heavy and big. I will lose some clearance. And there are only ARB selectable locker for 14-bolt. While for the 10-bolt axle I can find an OX selectable locker. OX is better then ARB.



Yes, this axle



Ahah me too! If I swap rear 14-bolt, I'll swap front 9.25" and will put an ARB in it. Full locked truck is a mud king



Dont wanna TrueTrac, but ist a good point. I suppose the OX locker is as strong as TrueTrac. Thanks.

The TrueTrack may give you better performance if your mostly street, else your (selectable) locker is one-legging it most of the time. G80 or actual detroit lockers are an option as well. With the TT, If you raise a wheel offroad, a little brake will balance it out. As far as IFS, no one makes a locker for the 8.25, it's too fragile, and ARB is the only one I'm aware of for the 9.25 IFS.

 

[Joseph Garcia]

When I upgraded to a 14 bolt rear end, I installed a TrueTrac along with a 4.10 gear set, and I absolutely love it. I am a 99+% street truck runner.