1978 J20 Axles for a YJ

[Hugh]

Hi All,

Question: I have stock dana 35/30 in my 92 YJ. I want to upgrade the axles. A 1978 J20 axle set has come up for sale. D60 rear, D44 front. Price: $100. Jeep has not been wrecked.

I think the J20 axles are 6 bolt, and about 6" wider than my YJ 60.5" WMS to WMS distance. I also believe the D60 in this rig has about a 6" offset to the passenger side.

When I put in new axles, I will also be doing a spring over conversion AND an Atlas II 4SP to accomodate Passy or Driver side front axle drop.

Am I getting into a LOT of work here, or should I jump on it? I'm not really interested in having the tires stick out 3 inches more on each side of my rig, altho offset rims might help with that a little.

Thanks!:)

[McRoth]

Sounds good. The J20 axles will be 8 lug though. Make sure you have a good double cardan joint on the rear shaft though, that's not going to be a real good angle on the DS.

[Bama Burden]

if that D60 is a 6 lug, then it's a semi-floater

[KaiserMan]

if that D60 is a 6 lug, then it's a semi-floater

Nope, if it's a 6 lug, then it's not a Dana 60. Jeep used 5 lug semi floating and 8 lug full floating Dana 60's.

If this 78 has 6 lugs alxes then it's a J10 with D44's front and rear.

The trucks axles will be alot wider then your Wranglers.

J20 front D44HD wms is about 67", and the rear D60 is a little wider.

[Hugh]

Here's what the guy told me:

all i know is its 6 lug and its either 4:09 or 3:73 gear ratio

And here is a link that states the following:
Rear axle type . full-floating hypoid
Final drive ratios 3.73:11, 4.09:1


http://home.off-road.com/~ozifsja/tech/reviews/j-20.htm

[J4GRAND]

all i know is its 6 lug and its either 4:09 or 3:73 gear ratio

And here is a link that states the following:
Rear axle type . full-floating hypoid
Final drive ratios 3.73:11, 4.09:1


The second part from the link is correct in that a J20 axle is a full-floater with either a 3.73 or 4.09 ratio. If it is a 6 lug axle, it is not a J20 axle. The J20s only had 8-lug axles; 6 lug axles were found on J10s and are Dana 44s.

[Bama Burden]

Nope, if it's a 6 lug, then it's not a Dana 60. Jeep used 5 lug semi floating
:o I can't keep the J-truck stuff straight

[scotty]

what size tires do you run on your yj?

33s or smaller,i wouldnt screw with the 60/44. the 60 is an upgrade,but has 44 sized shafts. to make it compareable to a d70 or gm 14 bolt you need to spend some $$ on boring out the spindles,some custom shafts,and a 35 spline locker(or side gears,i guess if you wanted to stay open :rolleyes: ). at any rate,you prolly dont need the extra size and beef of a 3/4 to 1 ton rear with small tires.

IMO if you want to stay skinny,and arent running bigger than 33s,youre better off staying with a driver side diff and obtaining axles from an 80+ narrow track wagoneer/grand wagoneer. all will have a 44 front and a centered rear. 80-85 will have an amc 20 rear,wich IMO is a better axle than a 44,and very common. if you believe all the hype that mags beat into your skull that the 44 is the axle to run,then 87 and up will have a centered rear 44 instead of the m20. from what ive read,you could find a 44 or an m20 in 86.

if youre going to run a 35+ sized tire,i still wouldnt screw with the 44/60. ;)

again,the 60 needs cash thrown at it to be as strong as a stock 70 or 14 bolt. you can mix and match axles if you want to stay skinny-waGGY narrow track front(pre 80 for passy drop,post 80 to stay driver) and a cab and chassis 14 bolt rear(63.5"wms) that needs no upgrading other than a conversion to disc brakes.

if you want both axles from a single parts rig and can handle being wider,seek out a 77ish or newer chevy truck-10 bolt front(better than a 44 IMO) and 14 bolt rear(single wheel WMS 67.5").

my 2 cents,for what theyre worth :thumbsup:

[Hugh]

Great comments...I run 34x9.50 inch TSL Special Service and will be upgrading to 36 inch with the new axles. I am past the limit of the Dana 35, and while Dana 35 upgrades are available to increase axle strength and eliminate the C clip, it is still a D35.

I may go the big bearing ford 9 inch route...thoughts?

Thanks!

[ChiefTawny]

When i blew the guts out of my d35, i put a 8.8 in. came out of a '01 exploder, had disk brakes, and had the 4:10 gears already. i paid $400 at the local yard for it. lug pattern is the same and its about 1/2" narrower than the d35. i beat the crap out of it and have no problem with it. im running 35" tires and a locker too!

[scotty]

I may go the big bearing ford 9 inch route...thoughts?


leave it for the street rod crowd. the ford 9" is,IMO,one of the most over-rated axles in the history of axles. its a 1/2 ton axle with 31 splines at best in a stock axle,and a pinion thats lower than anything else out there.

"but you can get nodular centers,40 spline shafts and you can build them,blah blah blah" is the argument for the 9 inch. you have to chunk a bit of $$ into a 9" to make it anywhere near as strong as a $150 junkyard 14 bolt. its not worth it. youre still left with a low pinion,or a reverse cut ring gear,which is not so great for a rear axle. and the design of the axle makes it want to blow out the stock center,and spit nodular centers right out of the housing :eek:

"but a 14 bolt is so heaaaavy and it hangs so looooow" is the argument against the 14 bolt. i dont think its bad to add UNSPRUNG weight. it increases the contact pressure of your tires and helps you keep the rubber side down. after i kept breaking 44s in my GW,i decided to put in a 14 bolt. i worried about the weight also,but after i got it installed and wheeled it i love it-one of the best mods ive ever made. the extra unsprung weight let me go places in 2wd that i needed 4wd to get to before,and i have not had one single prollem with it since. rear axle breakage is a thing of the past.

on the clearance issue,you can shave a 14 bolt from mild to wild. you can gain an inch of clearance with a grinder and no other fancy plating or ring gear turning. i cut the lip off of mine and smoothed out everything else,and i only have 1/2 inch less clearance than under my 10 bolt front(12 and 11.5 inches with worn out 38" TSL SXs). i know it drags(the paint is gone :thumbsup: ),but it slides over stuff and rarely is an issue.i follow my friend around just fine that runs 36" buckshots on a 10/12 bolt.hes got alittle more clearance,but i go thru the same ruts that he does.

i wheeled my rig with 38s and an auto with the stock 44/m20 for a couple years,and they lived with a conservative driving style. 36s would live for you with the 80+ 44/m20 with the same conservative driving.

if youre a "make it or break it" kinda guy,and want to take it out and beat on it without worrying,then there is no question.shaved 14 bolt rear,and 44 front. just make sure you have some extra shafts,as youll need them now and then with the 44 front ;)

one thing youll see me say alot: you cant beat the "beef per $$ spent" ratio of a GM corp 14 bolt.

[Hugh]

You'll get no arguement from me on a late model GM 3/4 ton 14 bolt, and I agree with you on the unsprung weight:thumbsup: If I had an axle fab shop around here that could cut and paste a 14 bolt to jeep dimensions I would jump on it. Do you know of any 14 bolts that match the Wrangler 60.5 WMS-WMS dimensions, or thereabouts, and are centered up in the rear punkin?

[1x1_Speed_Craig]

33s or smaller,i wouldnt screw with the 60/44. the 60 is an upgrade,but has 44 sized shafts. to make it compareable to a d70 or gm 14 bolt you need to spend some $$ on boring out the spindles,some custom shafts,and a 35 spline locker(or side gears,i guess if you wanted to stay open :rolleyes: ). at any rate,you prolly dont need the extra size and beef of a 3/4 to 1 ton rear with small tires.

Another option is to run a NT Waggy/Grand Waggy D44 front (as suggested by Scotty) with an Isuzu Rodeo D44 rear (4.10 factory gearing available, disc brakes, 6 x 5.5" bolt pattern, 58-60 3/4" WMS-to-WMS {depending on the year}). That's the setup I'll be running on my CJ-10a conversion project (http://www.greatlakes4x4.com/showthread.php?t=27185). I'm just having the front GW axle regeared to 4.10, and I'm adding manual lockouts & a Detroit Truetrac.

Craig

[scotty]

. Do you know of any 14 bolts that match the Wrangler 60.5 WMS-WMS dimensions, or thereabouts, and are centered up in the rear punkin?

all 14 bolts have a centered pinion. the C&C dually is 63.5" WMS,wich equates to roughly 1.5" wider per side than your wrangler. my guess is that youd never notice 1.5" ;)

one point of interest-the C&C andd SRW axles use the same width housing and the same axleshafts,with the difference being in the wheel mounting surface on the hub,and the location of the tabs to bolt the drum backing plate on the housing. this gives you the option of making a 63.5" wms 14 bolt simply by swapping dually hubs onto a SRW axle. you can use the drums on the SRW axle,or you can swap on discs.

further questions? :drivin:

[Hugh]

You're gonna make a 14 bolt fan outta me yet...check this site out http://www.pirate4x4.com/tech/billavista/14b_bible/index.html

Ok, your thoughts are great...63.5 inches is close enuf for YJ work:D There are recommendations on that web page for 14 bolt donor trucks, from 1973 to 1991. Any particular thoughts on favorites? I will want disk brakes.

I feel like I've been wandering around in the 9 inch, Dana 60, and Dana 44 desert, and I've found a 14 bolt watering hole:thumbsup: Of course, if someone were to drop a couple of dana 60s or 70s in my lap, I probably wouldn't gripe:)

[scotty]

oops,i just sent ya a PM with a link to the 14 bolt bible. looks like youve allready seen it :o

anyway, thats one of the great things about 14 bolts. they are virtually unchanged from 70 to 91 so theyre incredibly easy to shop for. you should be able to easily find one anywhere from free to $200.

if you use a single wheel axle,there are many bolt on caliper brackets that use a front rotor and caliper for an easy,relatively cheap disc brake setup. if you use a C&C housing,or a dually hub on a SRW housing, youll prolly have to fab it yourself. A&A mfg sells weld on caliper brackets for about $7 apiece if you dont have a prollem with welding them to your axletubes. use a front 3/4 ton rotor and caliper. use a 78ish caddy eldorado rear caliper if you need a mechanical E brake.