Axle ratio recommendation
07-10-2021, 06:51 PM
#11
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There is still a disconnect somewhere. Verify that those gears are actually coming from a JKUR (a rubicon).
Rubicons have a pair of D44 axles, not a D30/D44 combo. Front gears from a rubicon D44 will NOT work in a D30. The rear gears from a rubicon will work in your non-rubicon rear D44.
The JK D30 has a carrier break between 3.21 and 3.73. So, the carrier you have is good for only that 3.21 ratio. A different carrier is needed that will hold all higher numeric ratios (3.73/4.10/4.56/4.88/5.13/5.38). Last I saw these were in the 90-100 range.
Again, consider just having the shop source your parts...
Rubicons have a pair of D44 axles, not a D30/D44 combo. Front gears from a rubicon D44 will NOT work in a D30. The rear gears from a rubicon will work in your non-rubicon rear D44.
The JK D30 has a carrier break between 3.21 and 3.73. So, the carrier you have is good for only that 3.21 ratio. A different carrier is needed that will hold all higher numeric ratios (3.73/4.10/4.56/4.88/5.13/5.38). Last I saw these were in the 90-100 range.
Again, consider just having the shop source your parts...
07-11-2021, 06:15 AM
#12
JK Newbie
Thread Starter
Thanks nthinuf, for your explanation. I got it now. I also understand the difference on the front carrier now.
Thanks again, I will keep surfing the net.
Thanks again, I will keep surfing the net.
07-11-2021, 08:06 AM
#13
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I know when I upgraded to my PR axles, I sold mine at a great price and gave someone a nice upgrade over their 30/44 combo.
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mrjaja (08-12-2021)
07-11-2021, 06:40 PM
#14
JK Newbie
Thread Starter
Ryan0260,
If I find Rubicon D44 axles Front and rear, will there just slide in, or do I have to modify Trailing arm mounts Brake system and more? if there just plug and play, I will try to find some here in CA.
One more Question for the front carrier, Does the D30 has 27 splines ore is there a difference?
Thank you.
If I find Rubicon D44 axles Front and rear, will there just slide in, or do I have to modify Trailing arm mounts Brake system and more? if there just plug and play, I will try to find some here in CA.
One more Question for the front carrier, Does the D30 has 27 splines ore is there a difference?
Thank you.
07-11-2021, 07:00 PM
#15
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Rubicon axle housings will bolt right up. Same mounts, same hubs, same brakes. All you would have to do is run wiring for the e-lockers and add switches. (maybe you will get lucky, but don't expect to find a great deal on these...)
Here is an example of the carrier, search around and see what prices you can find. (looks like they went up a bit from the last time I priced them)
https://www.northridge4x4.com/part/y...p-carrier-case
The D30 has 27spline inner shafts (into the carrier/gear), and 32spline outer shafts (from the u-joints to the hubs). The rear D44 has 30spline shafts. If you decide to get limited slips/lockers, you will use the 27sp front and 30sp rear.
If you end up with rubicon axles, they will be 30spline inner/32spline outer for the front, and 32 spline for the rear shafts.
One more note on rubicon axles : starting in 2012, they added the option of either 3.73 or 4.10 gears. All prior years were 4.10 only. If you find a pair of axles, note the gearing just so you know what you are getting.
Here is an example of the carrier, search around and see what prices you can find. (looks like they went up a bit from the last time I priced them)
https://www.northridge4x4.com/part/y...p-carrier-case
The D30 has 27spline inner shafts (into the carrier/gear), and 32spline outer shafts (from the u-joints to the hubs). The rear D44 has 30spline shafts. If you decide to get limited slips/lockers, you will use the 27sp front and 30sp rear.
If you end up with rubicon axles, they will be 30spline inner/32spline outer for the front, and 32 spline for the rear shafts.
One more note on rubicon axles : starting in 2012, they added the option of either 3.73 or 4.10 gears. All prior years were 4.10 only. If you find a pair of axles, note the gearing just so you know what you are getting.
Last edited by nthinuf; 07-11-2021 at 07:08 PM.
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mrjaja (07-12-2021)
07-11-2021, 07:19 PM
#16
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What nthinuf said. Direct bolt in, no setting up of gears or buying new carriers. Add wiring and switches and have lockers as well. It is a good upgrade if you can't find a deal on them.
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mrjaja (07-12-2021)
07-12-2021, 06:21 AM
#17
https://www.morris4x4center.com/jeep...atio-chart.htm
so I have a 16 Rubicon. 6 spd MT on 35's,,,with stock 4.10 gears......its fine, long hills here in Pa on RT84 I drop back to 5 and if I wanted cud run them at 80 mph.....I believe a couple folks mention plan ahead (looks like ya did) I like the 4.10's...think its the better choice..btw 60 in 6th is like 1850 rpm....good luck however ya go
so I have a 16 Rubicon. 6 spd MT on 35's,,,with stock 4.10 gears......its fine, long hills here in Pa on RT84 I drop back to 5 and if I wanted cud run them at 80 mph.....I believe a couple folks mention plan ahead (looks like ya did) I like the 4.10's...think its the better choice..btw 60 in 6th is like 1850 rpm....good luck however ya go
08-05-2021, 06:14 PM
#18
Rubicon axle housings will bolt right up. Same mounts, same hubs, same brakes. All you would have to do is run wiring for the e-lockers and add switches. (maybe you will get lucky, but don't expect to find a great deal on these...)
Here is an example of the carrier, search around and see what prices you can find. (looks like they went up a bit from the last time I priced them)
https://www.northridge4x4.com/part/y...p-carrier-case
The D30 has 27spline inner shafts (into the carrier/gear), and 32spline outer shafts (from the u-joints to the hubs). The rear D44 has 30spline shafts. If you decide to get limited slips/lockers, you will use the 27sp front and 30sp rear.
If you end up with rubicon axles, they will be 30spline inner/32spline outer for the front, and 32 spline for the rear shafts.
One more note on rubicon axles : starting in 2012, they added the option of either 3.73 or 4.10 gears. All prior years were 4.10 only. If you find a pair of axles, note the gearing just so you know what you are getting.
Here is an example of the carrier, search around and see what prices you can find. (looks like they went up a bit from the last time I priced them)
https://www.northridge4x4.com/part/y...p-carrier-case
The D30 has 27spline inner shafts (into the carrier/gear), and 32spline outer shafts (from the u-joints to the hubs). The rear D44 has 30spline shafts. If you decide to get limited slips/lockers, you will use the 27sp front and 30sp rear.
If you end up with rubicon axles, they will be 30spline inner/32spline outer for the front, and 32 spline for the rear shafts.
One more note on rubicon axles : starting in 2012, they added the option of either 3.73 or 4.10 gears. All prior years were 4.10 only. If you find a pair of axles, note the gearing just so you know what you are getting.
08-12-2021, 09:58 AM
#19
JK Newbie
Thread Starter
OK, I can get this setup. and it should bolt right up to my 2008 JK. I am correct? Sorry for that double posting.
Dana 44 front AND rear axles Gen III M210 from 2021 Wrangler Diesel (Sport). These axles have 3.73 gears and a limited slip diff in the rear axle.
Dana 44 front AND rear axles Gen III M210 from 2021 Wrangler Diesel (Sport). These axles have 3.73 gears and a limited slip diff in the rear axle.
08-12-2021, 10:44 AM
#20
JK Jedi
Have you ever swapped axles? Even if those weren't JL axles, it's not worth the effort to swap axles for 1 step in gears. It's literally a fart in the wind, maybe 100rpm difference in a gear. It just ain't enough to mess around with. Also, nobody installs used gears (questioning above). Gears don't cost enough to go through all that work to put in used gears and risk them crapping out. If you're keeping the jeep for a while it's worth the price to simply regear it properly. Over the life of ownership the cost to do so is minimal.
If you have a buddy that will go pick up axles for you, install them for you, then find someone to buy your axles with turd 3.21's in em and haul them off for you.....all for free, THEN maybe it's worth an axle swap for 1 step in gearing.
If you have a buddy that will go pick up axles for you, install them for you, then find someone to buy your axles with turd 3.21's in em and haul them off for you.....all for free, THEN maybe it's worth an axle swap for 1 step in gearing.