'14+ rear axle swap

smcgillis10 · August 9, 2016

Has anyone swapped the rear 8.~ read end in these to a 9.5 out of a 6.2l? I want to swap gears to 3.73~ and thought it might be better all around to get the bigger axle with those fears already installed.

Sent from my iPhone using Tapatalk

LongrangeLauber · August 9, 2016

V6 engines have the 8.6" rear housings, the 5.3L has the 9.5" axle, and anything with the max trailer package or the 6.2L have a 9.76" axle. The 8.6" is by far the easiest to find aftermarket gears for, but they are slowly becoming available for the bigger two as well. I believe each of the larger two are available in an oem 3.73 gear

Silvern Sentry · August 9, 2016

6.2 Gears are actually smaller than 5.3 Gears (3.23 vs 3.42 w/o trailing, 3.42 vs 3.73 w/ max trailing).

Smaller is not really the right term, rather it has less teeth. But I am no expert it that area. I do know however that you can fit 4.10 gears in these diffs and you can also get a bigger diff cover which allowed more fluid (runs cooler).

smcgillis10 · August 9, 2016

V6 engines have the 8.6" rear housings, the 5.3L has the 9.5" axle, and anything with the max trailer package or the 6.2L have a 9.76" axle. The 8.6" is by far the easiest to find aftermarket gears for, but they are slowly becoming available for the bigger two as well. I believe each of the larger two are available in an oem 3.73 gear

Ok. So I have the 9.5 12 bolt. I confused myself since the front is the 8.25. Thanks.

Sent from my iPhone using Tapatalk

LongrangeLauber · August 9, 2016

Ok. So I have the 9.5 12 bolt. I confused myself since the front is the 8.25. Thanks.

Sent from my iPhone using Tapatalk

Yeah the front has pretty much remained untouched since '99

07Softail · August 10, 2016

V6 engines have the 8.6" rear housings, the 5.3L has the 9.5" axle, and anything with the max trailer package or the 6.2L have a 9.76" axle. The 8.6" is by far the easiest to find aftermarket gears for, but they are slowly becoming available for the bigger two as well. I believe each of the larger two are available in an oem 3.73 gear

They are not making OEM 3.73's for the 12 bolt 9.5, only the 9.76 has a factory option 3.73.

RT

hirdlej · August 10, 2016

Can you point me to a larger capacity cover? I would love this before I do my first fluid change.

you can also get a bigger diff cover which allowed more fluid (runs cooler).

Silvern Sentry · August 10, 2016

Can you point me to a larger capacity cover? I would love this before I do my first fluid change.

Try B&M racing I know they have one for the 2500 diff. They are same folks who make flowmaster exhausts so quality stuff.

grampadirt · August 10, 2016

http://www.mag-hytec.com/

LongrangeLauber · August 10, 2016

I've only seen one on the market for the 9.5" 12 bolts

sdeeter19555 · August 10, 2016

PLM maybe?

Sent from my SAMSUNG-SM-G900A using Tapatalk

Silvern Sentry · August 10, 2016

http://www.bmracing.com/products/71505-cast-aluminum-differential-cover-for-gm-95-blk/?mk=&yr=&md=&smd=&eng=

This one says GM 9.5 but says 14 bolt. I just remember seeing them do a giveaway on IG.

Notes say:

Load bolts provide additional support to bearing caps

So they are adding 2 bolts? Not an expert here.

From instructions:

9. We recommend running a M8-1.25 tap through each threaded cover hole on the axle housing to ensure an accurate torque on all bolts.

10. Install the supplied load bolts in each boss from the inside of the B&M Cast Aluminum Rear End Cover as shown until they bottom out (See Figure 3 & NOTE: There are two load bolt lengths. The 3 1/16” load bolt should be touching the bearing cap with the retaining bolt.