Upgrading gears

[jeephreak]

So, I've got a 30 in the front and a 44 in the rear (that didn't sound right...) with 3.21 gears. I misread the sheet at the dealer and thought I had 3.73's. This doesn't matter since I've since put 35" shoes on the JK, and, without a surprise, it's lagging a little at times as a daily driver. I was pricing gears and it looks as if 4.56 or 4.88 would put me in the right range for my use. 4.56's are higher than the 4.88's (popular?) and installation looks to be around 2K at the local dealer... ouch. They're the closest 4X4 shop in the area besides another who has a bad rep. I've got some mechanical background in the marine arena so I don't think it's out of my grasp. Anyone do it themselves, and is it a grand undertaking? Like I said, it's my DD and I can't have it down past a weekend. Thanks in advance for the input.

 

[PoliceMonkey161]

Yes, I have re-built many of axles including the D30 and D44. It's not overly difficult, but it's extermely time consuming to do it correctly. Your largest purchase will be the speciality tools for the DIY'er. Some machine shops can move the bearings from the carriers (call around, not everyone does it), but it's likely for what two will axles will cost in sub-contracting that work you could buy your own bearing puller set and press. You will also need a couple of other tools as well, dail calipers, larger scokets and wrenches, race tool, etc. The other major expense will be a hydualic press to put the bearings back on.You can have it done at a machine shop however with Dana axles the shims are on the inside between the carrier and bearing so you'll need to remove the bearing several times during set up to get your depths right (you can also buy set up bearings that slide on and off or make your own buy honing out the old bearings that come off).

This will be in addition to the research and possibily books that you need to do/buy. So, you can see why the shop charges so much......... If you deciede to move forward on your own, keep in touch, I have some great info I'd glady pass on to you.

 

[ralavoie_417]

$2000 is way too much. You can probably buy two new Dana 44s already geared at 4:88 from Dana Spicer for a few hundred more. Check out their website if you plan on spending that much loot. Re gearing axles is easy, if you've done it many times before. I have had my axles geared about 3 different times, price us about $600 an axle. If you're on a budget do the rear first, disconnect the front driveshaft and do the front at a later time. The only downside is no 4wd.

 

[jeephreak]

Thanks. Thought about the 'one axle at a time' approach, but, with the season changing and projected heavier than normal snowfall, that may not be a suitable fit for me at this time. I'm going to build more into the mod fund, and, when I can get both sets, I'll go from there. I'll hit you up PoliceMonkey if I take the plunge myself.

 

[jfrabat]

I would try looking at speedshops. They also have tons of experiene changing gears, and, many times, are cheaper than 4x4 shops.

 

[Utah_jeepster]

A 1000$ per axle is 500$ too much. most axle/diff places charge around 500$ per axle to purchase,set up new gear sets. But here is the rub, your 3:56 or 3:73 or what you have in your front Dana 30, the carrier itself will not support 4:10 or higher gears. the break point is 3:93 and 4:10 to where you have to change the carrier to hold higher gears.
As to people telling you its not that hard, well it is. The pinion gear has to be set from the center line of the axle shaft to the right depth and pre-load. This is a trail and error method for most backyard mechanics. And a dana 44 isnt a crush sleeve, its a .06 pre-load on the pinion bearing to a turning resistance of 15lbs at 215lbs of torque on the pinion nut.
If all of this sounds greek then dont worry, most axle shops,speed, or off-road places can help you. But if you never set up an axle before, or dont want to purchase the specilized equipment, then have an axle shop set up your gears for you.

 

[PoliceMonkey161]

A 1000$ per axle is 500$ too much. most axle/diff places charge around 500$ per axle to purchase,set up new gear sets. But here is the rub, your 3:56 or 3:73 or what you have in your front Dana 30, the carrier itself will not support 4:10 or higher gears. the break point is 3:93 and 4:10 to where you have to change the carrier to hold higher gears.
As to people telling you its not that hard, well it is. The pinion gear has to be set from the center line of the axle shaft to the right depth and pre-load. This is a trail and error method for most backyard mechanics. And a dana 44 isnt a crush sleeve, its a .06 pre-load on the pinion bearing to a turning resistance of 15lbs at 215lbs of torque on the pinion nut.
If all of this sounds greek then dont worry, most axle shops,speed, or off-road places can help you. But if you never set up an axle before, or dont want to purchase the specilized equipment, then have an axle shop set up your gears for you.

Actually, his profile says he has a 2012 JK......It has a crush sleeve, unlike your TJ has uses calculated torsion. Regardless, each has it's challenges. Personally, I like to be optimistic/incouraging and help folks develop their own plan as to thier upgrades. With the proper research, ability to due mathematics and the proper set up tools, setting the pinion depth in more time consuming than difficult.


As for the total the shop is charging, the real question is what are they suppling for $2000? Yes, that would be high for labor alone, but keep in mind labor here in Maryland may be higher than AZ and whatever shop does it has put their name and reputation on it..... Just a thought.

 

[ralavoie_417]

I have never attempted to set a ring and pinion. I wish I had the opportunity to gain that experience though. This past week I was at the SEMA show on Las Vegas. Dana Spicer had a booth and demonstrations to show people how to properly remove and set new gears. The guy doing the demo kept insisting to take notes as you remove the old ring and pinion. More specifically taking measurements so you know how many shims to use when setting the pinion. He sure made it look very simple, however I do know it is a very tedious job to take on. If you can afford the time to do it yourself, you should. If you're like me you will pay a shop. Like previous posts have mentioned a reputable shop is very important. I usually ask questions I already know the answers to and see if the shop workers know what they ate doing.
Keep us posted and let us know what you decide, specifically what gears you went with and the results you ate getting with your jeep.

 

[Utah_jeepster]

Personally, I like to be optimistic/incouraging and help folks develop their own plan as to thier upgrades. With the proper research, ability to due mathematics and the proper set up tools, setting the pinion depth in more time consuming than difficult.

Normally I also encourage people to try things, but your average backyard mechanic doesn't have the required skill set, nor tools to set up a new gear set. Where .012 off just on your pinion depth will put you .035-.045 off the peak convex gear head, still allowing your gears pattern right and run the average 10-15K before you chuff the leading or trailing edge making them whine on either the acceleration or coast side.
With the cost of gears, carriers, master install kit, and the specialized tooling required its better to have a professional who does this for a living set them. In such a critical area where a few thousands of an inch makes or breaks the set up. Where the national average cost is 250$ per axle, thats 500$ well spent when you can literality drop 2600$ (gears,lockers,install kit)on a single upgrade.

 

[jeephreak]

Great food for thought. I had a feeling I couldn't gear up to the 4.88 with my current setup but wasn't sure. Now I have to factor in the additional cost of the carrier. Even if I do go to a shop, which I might, I'll approach it with this info in hand as opposed to walking in and handing it off blind. The speedshops seem to be an out of the box approach and may save me some money. This whole idea came up due to the fact that I kept stalling the Jeep when backing out of a parking space and moving into first gear. I have to rev it to get it going. I tried some hill climbing in my yard (I'm sure the neighbors love me now) since I did that prior to the change of tires and let it crawl up on its own. Originally, it would climb without any assistance. With the addition of the larger tires, I had to help it a little. The idle is fine so I started approaching it from this angle. 35's on 3.21 gears suck. Should have made sure beforehand but I was just so damn happy to get a new Jeep. It's a learning curve.

Thanks for the advice. I'll update when I start compiling costs in this area.

 

[jfrabat]

Certainly sounds like you need new gears. Since you are thinking about changing the carrier, maybe it's a good idea to take the opportunity to drop in a locker... You will pay the same for labor!

 

[jeephreak]

Certainly sounds like you need new gears. Since you are thinking about changing the carrier, maybe it's a good idea to take the opportunity to drop in a locker... You will pay the same for labor!

Great. I knew someone would go there and convince me.

So... air lockers?

 

[jfrabat]

I have ARB, and love them. Only thing I would recomend is using acquarium hoses and inserting the ARB hose INSIDE the acquarium hose to protect the line, so that the lines are not as fragile. Also, if you do a lot of water fording, you can take the filter off the ARB conpressor, and use the thread to connect a fitting, and connect to the engine filter (I used the line that goes from the valve cover to the filter, and put a T on it), so that the snorkel protects not only the engine air intake, but also the compressors... And PLEASE, don't ask my WHY I had to come up with this idea!

 

[UnlimitedLJ05]

Not sure about the JK's but, should be the same price range. I had my Jeep regeared at Jeep Master's in Austin,Tx and it was 400 an axle for labor and the gears themselves were 200 a set plus a hundred a axle for the rebuild kits you need. I think with everything it was right at 1,700 including the new speedo gear I needed to match my tires to the axle ratio. Those little speedo are expensive almost a hundred bucks a pop.

 

[UnlimitedLJ05]

Sorry looking back at my invoice it was 1880 for everything. Which was cheap compared to everywhere else I checked. Dealer's in the area wanted 2200 or so to do it. If you ever need major work done in Austin go to Jeep Masters. Bo and Ray are 20 year chrysler mechanics that run the place and are very nice to deal with. I droped my Jeep off at 10:00am and by 4:00 PM got the call to come pick it up. I also liked they gave me back my old gears and bearings though I didn't ask for them.

 

[jfrabat]

I got charged about $3.4K when I did mine back when I lived in Miami, but mine included alloy axles and ARB lockers (I also took advantage that I was doing the work, and increased the spline count of the axles). The speedo gear I changed myself ($15 for the gear and 5 minutes of laber in my garage, but mine is a YJ).

 

[jeephreak]

Again, great advice especially involving running the line to the engine filter. Definitely using that idea.

 

[jfrabat]

Use that one if you have a snorkel... I killed a compressor when stuck on a mud bog (the compressor sucked in water, even though it was installed on top of the wheel well). When I replaced it, I decided to go the safe route, as I had to finish the trail without lockers, which kind of sucked!

 

[TrailRatedRN]

A 1000$ per axle is 500$ too much. most axle/diff places charge around 500$ per axle to purchase,set up new gear sets. But here is the rub, your 3:56 or 3:73 or what you have in your front Dana 30, the carrier itself will not support 4:10 or higher gears. the break point is 3:93 and 4:10 to where you have to change the carrier to hold higher gears.

I have 3.73 gears with the D30 in the front and D44 in the back. I've been banking some money with the intention to regear to 4.10 and add a locker in the back. Am I understanding from this statement that I will not be able to go to 4.10 because the D30 can't take it and I will shear my axle?

 

[jfrabat]

I have 3.73 gears with the D30 in the front and D44 in the back. I've been banking some money with the intention to regear to 4.10 and add a locker in the back. Am I understanding from this statement that I will not be able to go to 4.10 because the D30 can't take it and I will shear my axle?

If you are installing lockers, you are changing the carrier anyway, so both will take 4.10 gears (provided you put a locker in front as well, as your current carrier will not allow for 4.10).