Time for gears...lived with my 35s for long enough with stock gears. Tolerable on streets and freeway...WORTHLESS offroad with rocks, up and down steep hills, etc. Feels like the jeep is less capable (although the 35 tires are great for obstacles)!

Heres my setup:

08 Sahara
6 speed manual
2.73 txfr case
3.73 gears
rear lsd trac-loc
35in km2 tires
flashpaq set to 87octane

I've decided on 4.88 as opposed to 4.56. I'm hoping the high pinion setup we have will keep the gears from blowing up as compared to the low pinion of previous jeeps.

I will be doing ARB front and rear as well, although the trac-loc is fine, id rather do this install once (excluding any damage/repairs).

So..to get to my question! With the D30 up front, I've looked into a few options, and wanted hear from you with previous experience, or just good advice!

1. get the arb with 27 spline setup and use stock axle shafts
2. get the arb with 27 spline setup and get some chromoly shafts
3. get the arb with 30 spline setup and get some chromoly shafts
4. get the arb with 30 spline setup and get a d44prj with chromoly shafts (not really in the budget..but when is any of this ever in the budget!)

I'm tempted to just go with #1 and when it finally breaks, then put in some chromoly, but then I'm focusing on 27spline for X amount of years...

I definitely would rather have an axle shaft or ujoint fail instead of the gears or locker, no RCV for me at this time based on research I've done here, etc.

I've looked all over for a chart attempting to rate the failure limits of all the various setups (d30 stock, through the chromolors, d44, etc etc) to no avail.

Am I focusing too much on the spline count? Is the stock d30 just a waste of time and will bend/fail too quickly (ie shafts, then gusstes, then xyz... so many upgrades on a losing team....)

I try to tackle obstacles without much skinny pedal.. but stalling and testosterone get in the way of good judgement too often!

Thx in advance!

 

no suggestions??? I'd even settle for a "do a search" reply at this point :-)

 

I just did option 2 to my Jeep, also a Sahara, and kept the stock shafts as trail spares.

I figure with the 27 spline, at least they are available from multiplie vendors. The 30 spline D30 chromolys are only made by 1 company last time I checked, where as the 27 spline are available from many.

And does it really make THAT much of a difference in a D30 application? I didn't think so. Anyway, ARB air lockers front and rear, and front chromoly shafts is what I just did. Waste of money? Who knows.

I wheel with a guy in a TJ with a D30 front with chromoly shafts and 37" tires, and he is rock-solid, and knows what he's doing when driving.

Oh, and one final thought is the gears - i went straight for the 5.13's. For the money they cost to install, and the complete lack of freeway driving I do, the 5.13's were the ticket, and they are awesome. Actually got all my power back.

 

thx for the info! do you have auto or manual?

 

Option 2 is what I would do also. Or Get a pro rock 44 but that is pricey.

ARB , Gears, Overhual kit, Chromoly axles and a Compressor and you should be set.



David

 

I have an auto. Freeway RPM is a little high now, but I hardly ever drive freeway, I'm all city driving when it's not trailered behind the motor home.
Plus the lower gears will help the 2.72 transfer case when crawling.

 

I suggest doing it right the first time. Over and over we see guys that have done significant modifications only to change them later.

Obviously, I'm going to push the ProRock. Even if you bought a used Rubi housing you would still eventually sleeve, gusset and probably replace or reinforce nearly every piece of stamped steel bracket on the housing. The best recommendation is to go ProRock before you put ANY money into your stock housing.

Think of the average Rubi owner. Add a ProRock at the beginning before you regear and your ONLY additional cost is the housing. For this cost you don't have to sleeve, gusset, straighten or replace any brackets when they rip off on the trail. I certainly understand that a PR44 can cost more than if the owner does all of the work but doesn't your time and the hassle factor account for anything?

As a Jeep owner for many years, I can tell you I've wasted a lot of money on parts that I changed out later. Go with a plan and do it right the first time. In the end you end up with a much better rig with much less cost.

 

My .02 worth:

I just ordered RCV axles, Pro Steer ball joints and EVO sleeves for my D30 front; I gusseted my end forgings last year when I was still on 33s and I've been running 4.88s for some time.

Assuming a guy is going stick to reasonably sized rubber and isn't a lead-footed hillbilly, I don't think it's a waste of money to put a couple thousand into a Next Gen D30.

Having said that, the argument Dyna is making is quite persuasive, particularly if a guy brings a new JK home and begins a build right from the start. For those of us already heavily invested in our Jeeps, well, I guess it boils down to personal choice and how much more you think you can slip past the spouse.



I'll run my new 35s and muscled D30 and hope it holds together. If it doesn't, I'll be calling Northridge for a complete ProRock. Time will tell.

 

Agree with Dynatrac, but I went with your option #1. I have a budget and I figured I could just sell my D30 w/ ARB, gussets, and sleeves when it's time to upgrade to a D44. Yes it's about $1500 more in the long run (if I sell my upgraded D30 and upgrade to a geared and locked D44), but I have more money in my pocket from now until then for other upgrades.

If I could do it all over again, I'd probably have purchased a winch instead of the front locker, added the Evo gussets, and still re-geared. The performance and MPG improvements were well worth the cost of the re-gear. I'd run like that until I was forced to upgrade. I only did the locker because Northridge had a screaming deal on it and Evo did the install for next to nothing (they were doing my gears already).

There is much debate re: the shafts. The question is whether or not you would like to lose your shaft or your gears/third member/locker. Personally, I would rather lose a shaft.

Good luck with your decision.

 

I would do more research on 5.13s. Most people on the boards (including myself) have been very happy with 5.13s and the automatic.

My JK drives better and feels "faster" than stock 4.10s with stock tires. HWY RPMs are not bad @ approx 2300 @ 70 mph, with 17-19 mpg interstate. I haven't dropped out of OD in 5 months since the new gears.