When I bought my 09x the owner said it had heavy duty axles from the factory. I have a Dana 44 rear and a Dana 30 up front. I also have a towing package. My question is on the gearing, I'm running 305/70/16's with 4" rough counrty lift. Are the gears from the factory ok or do I need something different?

 

Gears will bring back the "umph" it lost with bigger tires. Otherwise, as long as there are no weird noises, the gears you have are fine.

Going to a higher (numerically) gear will make it more fun to drive, better off-road, better towing, and should bring your in-town gas mileage back a bit better.

 

for 305's, you should be alright with your 3.73 gears. i wouldn't bother regearing until you get up to 35" tires.

 

So what is heavy duty about the axles under your JK? I have the Dana 30 and I do not consider it heavy duty. Maybe he added gussets? Did he say he replaced the gears already? I was thinking based on your original post something might of been enhanced to make it heavy duty compared to stock?

 

Not sure if anything is heavy duty. I was just going with what I was told. I'm new to the jk world. I did the lift myself and after reading all the stuff in these treads i want to make sure I'm doing things right.

 

heavy duty? I wouldn't consider them heavy duty... the G2 Dana 60s I saw a while back I would say look heavy duty... but the 30 and 44 that are stock... not so much... well, i guess it's better than a prius.

 

The Dana 44 is considered 'heavy duty' from Jeep, especially since it's an upgrade.

 

The rear D44 is larger in most meaningful dimensions than Dana 44s before it. Example, the D44's ring gear diameter is listed at 8.5". The JK D44 rear is actually 8.9", almost the size of the revered Ford 9"

Now the JK front is interesting to me. The D30 seems to have a pretty good track record based on the threads here. Very few issues. I had a D30 front and never really trusted it so I swapped to a D44. It might be that 35" and under tires are fine with D30s. Knowing now the track record of the Jk D30, I'd prolly just leave it alone. Having the D44 is some peace of mind tho. Was it worth the $1150 I paid? Umm, yes . . . I guess.

As for gear strength, unless you are not satisfied with the ratio, the Dana oem ring gear and pinion are considered top notch.