Comanche build questions

[Pete M]

sure you're not thinking about the TJ dana 44?

[dunnc1991]

Pretty sure you're thinking TJ. JK axles are a whole different animal

[Megadan]

Nope, thinking of JK axles.  

[Pete M]

JK axles do have some weak points that show up when run under a 3 ton Jeep.  Should work great under a rig that is half that weight.  :thumbsup:   especially when you can buy a truss with XJ mounts already on it ready to go. :D

[Megadan]

I won't argue that, but they still have 2 big weak points.  Axle tubes that bend, and Upper C's that bend.  Sounds familiar...

[Pete M]

yup.  Jeep seems to like to engineer their Jeeps to only drive around on the pavement.  :dunno:  bastards.  :fs1:

 

but the JK axle really is a pretty good deal for the money. :yes:

[Incommando]

I pointed out that the JK REAR D44 may be the strongest D44 REAR ever. As to the fronts the JK D44 Rubi FRONT and The JK HP D30 front do fail. But they fail under circumstances that our MJ axles would fail also. A JKU may weigh 1,200 #'s more than an MJ BEFORE you add larger tires & rims, bumpers and other armor. Also the 3.6 JK/JKU has between 95 & 180 horsepower more than any stock MJ/XJ. Add in that the average tire size on most of these rigs where the failures are most common  is 37".   No factory rear MJ axle comes near the JK rear as it is an extremely strong unit with a larger ring gear among other things while the holy grail MJ D44 is weaker than the average D44 rear due to the tubes and diameter being smaller than any other. A front JK HP 30 is more stout than our HP D30's which are about a tie with a Rubi TJ D44 front IF you go to big u-joint shafts.  The JK Rubi HP D44 front is more stout than any of the other three front's listed. So JK axles under a lighter rig with less power and a smaller tire size would seem to be a solid upgrade.  :thumbsup:

 

 

Bring your MJ up to a 5,000+ # curb weight, bump it to 285 horsepower, and hit it even moderately while  running  37" tires on your stock MJ/XJ axles.  :rotf: I'll wait for a report back. 

[Tomx31]

Hahaha so I want to thank you guys once again for helping me out. So now my Axel plan right now is rebuild my front dana30 and truss it and get a ford 8.8 rear. What year is beat to pull the 8.8 out of? And what gear ratio should I run with 35' tires? My buddy recommended 4:88. Thoughts? What do you run in your rig?

[Incommando]

IIRC a '95 & newer solid axle explorer will get you the axle you want. The lowest ratio available stock is 4.10, though. If you are going to drop in a locker find an open version as there are more lockers available for less money.

 

Many folks recommend staying with a 4.56 for the D30. Apparently the 4.88 requires making the pinion thinner and creates a weak point.

 

Here is a pretty good primer on the 8.8 swap

 

http://www.jeepsunlimited.com/forums/showthread.php?371713-8-8-FACTS-OPINIONS-amp-HOW-TO-S-%28F-A-Q-%29

[Megadan]

The best year for the 8.8 is generally 96+ or newer.  31 spline axles and disc brakes.   
One recommended thing to do with the 8.8 is to circumference weld the tubes to the housing.

 

[Incommando]

my 1987 metric ton package has different setup then my 1990 regular 1/2 ton. both are 4x4 both have leaf springs.

I measure metric ton springs at 77 mm wide not tall. The 1/2 ton leaf is measured at 65 mm. Now I know my metric ton 1987 has never been moded and came right from dealer

Still waiting to see pics of those factory 3" wide Comanche springs instead of front International springs.