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Diff blown, swap to 14 bolt possible?

sinister

New Member
Joined
Dec 21, 2011
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7
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canada
Hello, I blew the rear differential in my 08 ltz. Could I use my 14 bolt with 3.73s? What would the negative effects be from that? Guess gas mileage a bit as it's much heavier
 
Following as the differential on my '03 is on the verge of grenading.
 
DO you have 4x4? if so gear ratio front and rear needs to be the same.

Can you put in the larger axle?
Sure My guess is you will need to weld all sorts of things and probably modify a bunch of others
 
YGMN is correct, you will have to make lots of modds to make the change.  R.
 
Well technically you can put a 14 bolt  9.5 inch semi floater axle from a 07up Escalade in. Is the juice worth the squeezing NO. (Old guy saying)

Put a Detroit Truetrac diff in it, if you want a more stout diff.
 
I'm running a 460 hp ATK 6.0 that I've added a supercharger to, probably well over 600 hp at crank.  Truck runs 13s, including this week at Indy Hot Rod Power Tour stop.  I've got the 10 bolt with a TrueTrac and love it.  The only issue I have is keeping the diff cover sealed.  7 of the 10 bolts are Stage 8 locking bolts but driving home from Indy this week noticed gear lube on back of truck.  Gasket failed on top side of cover, two of the non-Stage 8 bolts I removed without using any tools.  I put in those Stage 8s several years ago when I couldn't keep the cover sealed for more than a few months and it's been trouble free until now.  Should be able to see broken ends of the gasket in the pic.
 

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I know this is probably a silly question but did you locktite your bolts? Sounds like you need some red locktite.

I would probably do what I did with my Caprice. You can put the 14bolt internals into a 10 bolt housing if you really need to... My Caprice is like that... It also has 23 spline axles now (Was 20) Ford 3/4 ton wheel bearing assembly... No room for C clips so the ford outer bearing wheel assembly with tapered bearings keeps everything together. The guy that did it used to work for DTS and may do so again. So basically I have all the bonuses of the 14bolt  rear end but non of the hassle of upgrading to a true 14bolt rear end.

 
I used blue Loctite.

Interesting about the 14 bolt internals in the 10 bolt housing.  Seems like overkill to me for fairly stock trucks if a 10 bolt with TrueTrac 10 bolt internals can live in my truck, especially since my issues wouldn't be helped by the internals being different.
 
FYI - video of Wednesday's 13 second run and timeslip posted on FB group page.

Here's my timeslip:
 

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enoniam said:
I used blue Loctite.

Interesting about the 14 bolt internals in the 10 bolt housing.  Seems like overkill to me for fairly stock trucks if a 10 bolt with TrueTrac 10 bolt internals can live in my truck, especially since my issues wouldn't be helped by the internals being different.

It's not a 10 bolt housing it has a 14 bolt center section and is huge with 6 lug axles. When GM start putting in the 6.2 in 1500 trucks they knew the 10 bolt rear could not handle 400 plus horsepower so they came up with what they call a 9.5" Hybrid Axle.

PS its not a simple swap you have to change everything back there because the size of the center section

BTW I saw the video with you and the hellcat doing the smoky burnout. I bet he was surprised you could hang with him. :laugh:


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Byron, I think he was responding to me... My 94 caprice in storage has a highly upgraded rear end in it. I could likely run that car up to 1000 hp. It truly has the 3/4 ton internals in it but the posi was upgraded... Sort of like doing a stroker engine as he explained it to me.

Because of the size of the axles in that rear end the C clips dont have room... The ford tapered outer bearings prevent the axles from moving and he had to do some "clearancing" within the rear end. The cover is a supportive rear end to help provide strength. He told me it would be very strong up to 700 hp and suggested a Dana rear end if I ever break this one...  He of course didn't go through the whole process of what he did on my car but enough to understand what I got for $2500 back 10 years ago.
 
I didn't notice your post, I guess we got off topic again.
 
So to back up a little bit... I mentioned my custom build as an option.. Moving to a full 3/4 ton pickup rear end or bigger will be somewhat of a challenge because the 1500 avalanches are spring coil and pretty much everything else not SUV or 2500+ is leaf spring.
Not to mention the ABS might be different, the brakes will be different, and then there is the whole 8 lug over 6 lug issue... 

Having the smaller 1500 rear end is fine but you want to replace the components with better quality than what factory had. 

The other option that makes sense is doing what I did with my caprice and putting in the bigger internals. Uses the same external case so pretty much everything should still bolt up and work fine. But should be done by someone that knows what they are doing. The guy that did mine does them all the time and reinforced the case in places he needed to and trimmed where he needed to to make it fit. He also knew using the bigger axles like I did also means less clearance in the axles tubes and some other items he already knew how to get around.  But this option is probably the costliest... But also not obvious.
 
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