Differential Questions

DiasWindu

Member
Original poster
Joined
Aug 10, 2021
Messages
28
Location
Sydney
G'day Guys,

I joined this forum a year ago, but this is my first (maybe second, I don't recall) post, so be gentle lol. I also apologise if these questions have been answered before, I did have a quick search.

Last year I purchased my first Jeep, a 2005 TJ Golden Eagle. Because I'm Aussie, it came with the Dana 30 up front and the Dana 44 in the rear, geared to 3.73. Last year I also acquired a HP Dana 30 from a 96 XJ Cherokee (which is 3.07 I believe) and its my plan later in the year, to install it in the TJ. My ultimate goal is to run 33's (Australia has strict rules about tire sizes and lifts) with a re-gear to 4.56. I intend to use Revolution Gear ring and pinions when I finally get around to the install, and I have a couple of questions regarding parts.

1. I understand I will require thick cut gears for the Dana 44 due to a different carrier size used between higher and lower ratios. I know I will also require reverse cut gears for the HP Dana 30, but will it also require thick cut gears, or is the carrier size problem only with the Dana 44?

2. In regards to the Revolution Gear, ring and pinions, I notice they sell packages that come with master install kits etc. Obviously I would prefer this option to buying things separately. Can anyone tell me if the ring and pinions from the Dana 44 used in the XJs and TJs are the same? I'm asking because I can find packages for the TJ Dana 44/Dana 30 (which won't work because I need the reverse cut for the HP Dana 30) and the XJ Dana 44/Dana 30, but I don't want to buy the XJ package if the Dana 44 ring and pinion won't fit in the TJ diff.

If anyone is able to help educate a jeep newbie, I'd be grateful

Thanks for your time,

Emerson
 
Doing a quick search for "HP Dana30 carrier break" comes up with 3.55 - 3.73. I'm fairly certain the carriers are interchangeable from HP30 to LP30 so you should be able to reuse your carrier?

My instinct says the XJ and TJ Dana 44 gears are the same?

I would verify both questions with RGA when ordering, those guys really know their stuff.
 
G'day Guys,

I joined this forum a year ago, but this is my first (maybe second, I don't recall) post, so be gentle lol. I also apologise if these questions have been answered before, I did have a quick search.

Last year I purchased my first Jeep, a 2005 TJ Golden Eagle. Because I'm Aussie, it came with the Dana 30 up front and the Dana 44 in the rear, geared to 3.73. Last year I also acquired a HP Dana 30 from a 96 XJ Cherokee (which is 3.07 I believe) and its my plan later in the year, to install it in the TJ. My ultimate goal is to run 33's (Australia has strict rules about tire sizes and lifts) with a re-gear to 4.56. I intend to use Revolution Gear ring and pinions when I finally get around to the install, and I have a couple of questions regarding parts.

1. I understand I will require thick cut gears for the Dana 44 due to a different carrier size used between higher and lower ratios. I know I will also require reverse cut gears for the HP Dana 30, but will it also require thick cut gears, or is the carrier size problem only with the Dana 44?

2. In regards to the Revolution Gear, ring and pinions, I notice they sell packages that come with master install kits etc. Obviously I would prefer this option to buying things separately. Can anyone tell me if the ring and pinions from the Dana 44 used in the XJs and TJs are the same? I'm asking because I can find packages for the TJ Dana 44/Dana 30 (which won't work because I need the reverse cut for the HP Dana 30) and the XJ Dana 44/Dana 30, but I don't want to buy the XJ package if the Dana 44 ring and pinion won't fit in the TJ diff.

If anyone is able to help educate a jeep newbie, I'd be grateful

Thanks for your time,

Emerson

Yes, if you don't want to change carriers, you will need a thick ring gear for the Dana 44 as the carrier break is at 3.92.

For the Dana 30, the carrier break is 3.55 and below, and 3.73+. so you can reuse your existing 3.73 carrier. And of course as you stated, you will need the reverse cut. The XJ kit will be perfect for that.

I geared my HP Dana 30 and 2006 Dana 44 using an XJ kit, however the XJ Dana 44 was old and the carrier shims go under the carrier bearings, or inboard. The 2003-2006 Dana 44 uses shims installed outboard of the bearings, so the shims in the XJ gear kit will not be correct. So you need to buy the Yukon SK 708193 shim kit. https://www.amazon.com/gp/product/B0078UBZBS/?tag=wranglerorg-20

If you had a 2002 or older Dana 44, then yes the XJ kit would have worked perfectly. It's no big deal to buy the shim kit though, though it's kind of expensive, but it's necessary to get the job done.

So:

XJ kit
normal thickness reverse rotation Dana 30 ring gear using existing 3.73 carrier from LP axle installed into HP XJ axle
thick Dana 44 ring gear and existing 3.73 Dana 44 carrier
yukon SK 708193 outboard shims for Dana 44

Should be good after that.
 
Doing a quick search for "HP Dana30 carrier break" comes up with 3.55 - 3.73. I'm fairly certain the carriers are interchangeable from HP30 to LP30 so you should be able to reuse your carrier?

My instinct says the XJ and TJ Dana 44 gears are the same?

I would verify both questions with RGA when ordering, those guys really know their stuff.

Dana 30 carriers are the same regardless of pinion placement. Only differences are the carrier breaks and those apply to the same ratios for both pinion styles.

XJ/TJ Dana 44 gears are the same, it's the shims that matter. 97-02 TJ Dana 44 uses same inboard shims as XJ, 2003+ TJ went to outboard shims (Yukon SK 708193 fixes this)

I was able to consolidate this info during the regear of a YJ HP 30 and 06 TJ Dana 44. The XJ kit would work but need to buy additional outboard shims.

Now that I recall, I wanted to do the XJ kit but at the time couldn't, I had to itemize my parts so that the ones available would ship on time (I was in a rush). If I chose to stick with the XJ kit, Rev refused to ship it until all parts were ready to go, and there was no ETA in sight and I had a month of time to get it done. I chose to itemize, and received everything but the 30 R&P in my timeline, so I ordered Rough Country gears for the 30, and then ended up with the 4.88 R&P from Revolution straggling behind and delivered later. It is now on my shelf "just in case" the RC gears ever shit the bed. Since I had already purchased the Revs anyways hoping they would come, I figured I may as well keep them rather than send back. They can be a decent backup in case the RC stuff ever causes trouble which I doubt it will, I didn't feel returning for $180 or whatever it was was worth the squeeze.
 
Last edited:
  • Like
Reactions: JDM and SvtLdr
Good morning Guys,

Thanks so much for all the info. I really appreciate it.

Luckily I am in no rush, because it seems Revolution is out of stock for this stuff anyway.
 
Good morning Guys,

Thanks so much for all the info. I really appreciate it.

Luckily I am in no rush, because it seems Revolution is out of stock for this stuff anyway.

I looked this morning and they appeared to have XJ kits. But I’m not sure I checked 4.56. They had 4.10 4.88 and 5.13 I believe. Maybe consider 4.88 instead? For a 5 speed 4.0 on 33’s, many run and love that combo.

Edit, oops forgot you have an 05 6-speed. Yeah 4.56 is best unless you plan on AX15 swapping someday.
 
I looked this morning and they appeared to have XJ kits. But I’m not sure I checked 4.56. They had 4.10 4.88 and 5.13 I believe. Maybe consider 4.88 instead? For a 5 speed 4.0 on 33’s, many run and love that combo.

Hi Mate, thanks for the suggestion. Mine is actually a 6 speed. Would the 4.88 still be a better option?
 
Hi Mate, thanks for the suggestion. Mine is actually a 6 speed. Would the 4.88 still be a better option?

You replied too quick for my edit! I had forgotten you have the 2005/6 speed. I’d rather 4.56 for 33’s. Unless the 6 speed craps out, which a common fix for that is an AX15 swap. The AX15 does really well on 4.88/33’s (127km/h @ 3000 rpm). The 6 speed would be 3200 at 127km/h so it’s not really the ideal ratio although plenty do run equivalent setups. 4.88/33 would be about the same as 5.13/35 and there are a few here with the 6 speed running that. But to me ideally it would be 4.56 6 speed and 4.88 5 speed.