Narrowing diff vs having it narrowed?

4speedhandler

4speedhandler

TJ Enthusiast
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Apr 19, 2016
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anybody have thoughts on narrowing a front differential yourself versus paying a shop to do it?
anybody do this themselves? anybody pay someone? what are your thoughts and experiences?
im not staying stock width so if anyone has concerns with stock width dont worry.
my current thought is to take the fullsize f250 hp44 i have and shorten the long side to take a tj rubicon shaft and have a wms width of about 66.3" if my math is right.
what has everyone else done?
 
I had a GM 12 bolt narrowed to fit under a Vega project one time. That was a rear differential. Dutchman Machine performed the work for me. It was more of a pain in the backsides than it was worth. It's not so much getting the axle narrowed, it's getting axle shafts. That gets expensive in a hurry.

Never thought about it for a TJ. There's way too many good axles already set up for the front and rear available to do it yourself.
 
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I have done this both ways.
Once I had a shop narrow a rear axle for me and I narrowed a front axle myself.
A lot of time, measurements and skill required to DIY it. On the front axle, I took a 1976 Camper Special Dana 44 axle from a 3/4 ton Chevy truck and cut 9" out of the long side (in this case drivers side), axle tube. I re-attached and welded the inner "C" back in place making sure I had plenty of caster matching the passenger side to create a passenger "drop" wide-track CJ-7 axle for my Cummins 4BT powered CJ. Removed the 8x6.5" wheel parts and swapped them for 5x5.5" parts to match the CJ original wheel pattern. The axle tubes on a camper special GM axle in those years is spring-over, what I wanted and the tubes are 2 3/4"x5/8" thick beef! I did this because I had the axle already or I probably would have bought a Ford HP60 1-Ton to narrow instead. I saved a lot of money using what I had.
The rear axle was the popular Sterling design 2001 Ford Explorer 8.8 axle that I had narrowed to take two passenger side shafts making it almost exactly the same width as the original AMC-20 it replaced. This had the benefit of almost perfectly centering the housing, gave me 4-wheel disc brakes and a lot stronger 31 spline rear axle shaft assembly. The tubes on this axle were .250" wall and 3.25" diameter so bending moment for these tubes is a LOT higher than stock 2.500" Jeep. The axle shafts are 1050 steel as opposed to 1040 steel used in Dana axles. The shafts are 1.32" cross section, 31 splines with a better angle cut making the shafts up to 30% stronger part-for-part than comparable Dana 44 shafts. I re-drilled the flange out to 5x5.5" bolt pattern used on all CJ's so it would match the front axle. The ring & pinion in my camper special Dana 44 was 4.11 so the factory Ford 4.10 gears in the 8.8 matched my Chevy Dana 44 front perfectly. Detroit lockers, ring & pinions and armored diff covers were much less money and way more popular for the Ford Sterling 8.8 at the time over the AMC-20 housing that was paper thin. I used an 8.8 out back because it was only $125 at the time on 1/2 price day at the yard and I could lift it into the bed of the truck by myself!

This example vehicle had leaf spring suspension making it far easier to do than a TJ with coils and control arms. I think you will find it very expensive to narrow any axle, especially when you have to buy all the brackets for suspension to weld onto them afterwards. It just isn't cost effective unless upgrading to major beef, say to Dana 60, 10.5 or 14 bolt 1-ton class axles.

Rick
 
thanks for the thoughts guys.
i called up dutchman and they only do rears otherwise i'd just ship the 44 to them for narrowing. the cost of custom shafts is why i want to make the long side fit a stock length shaft.
Rick-i went a little overboard upgrading the rear with a ruff stuff full float 35spl 9" and an arb, so optimistically im trying to keep the front less than that so i can afford to get it done before my winter break to start assembling things under the vehicle. from your experience would you say that the $1100 a local shop wants for narrowing the housing is worth it? i priced out the artec brackets, and other parts i'd need and for me to narrow it would be like $375 but im not so confident in my ability to keep it straight when welding the brackets.
 
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Is the $1100 including the brackets welded in place and all labor to put the axle assembly back together?
If it is just labor to narrow and true the housing, that's steep. I paid $1100 for some parts & labor to basically do everything except new brake linings. Labor included buying from them a full case Detroit Locker, install kit, bearings, fully assembled less the gears, weld axle tubes to the housing to prevent tubes from spinning, armored diff cover and axle shafts I already had re-used.
It broke down like this:
$300 to narrow, remove old mounts and weld new perches to the axle in the correct spot & weld tubes.
$300 to setup gears with a new master install kit and install everything less new brake shoes.
$400 New Detroit Locker
$100 to weld new shock mount tabs to the axle
————————————————————————
$1100 everything
All I did was install new parking brake shoes and new pads on the calipers. Installed new rotors. Attach the parking brake cables, route the hard brake line and secure the breather tube vent. I de-greased the housing and painted it including the new mounts that were welded on. Installed armored cover with sealant. Installed the shocks Filled axle and install the unit under the Jeep. Lastly, bled brakes and installed the wheels with new shiny acorn lug nuts. Done!!

Still some work involved but ALL of the hard stuff was done by the shop at $1100.
 
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the $1100 was just narrowing, no brackets or anything else. so it kinda feels like i'd be getting ripped off because that assumes they need 10 hours at their shop rate ($110/hr according to the guy on the phone) to cut off one tube end and put the inner c back on. i would like to say i have all the skills needed to narrow it myself, im sure i could cut it and put the c back on and weld it , but as mentioned earlier i have no feasible way to straighten it or make sure it stays straight after welding. At the price point of buying the proper alignment jig for the c's as well as the thru bar to keep the housing straight the cost to do it myself ends up as much as paying the shop again.

When either of you guys narrowed your axles did you weld new brackets and c's on? how did you keep it straight? is it feasible to do without the thru bar setup as long as the weld temperature was well regulated and covered with a welding blanket?

i know it may seem like im asking too may questions or am too new to this to be building custom axles but i am really just trying to gather as much information and experience in one place as i can to see what has happened to other people when things went wrong and how to avoid or pre-plan for the problems. in the case that i need to narrow it without a shop at the minimum i'll get ahold of my buddy who is a far better welder than i and have him work his magic.
 
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