Lets talk Ultimate! A Crew Cab 6x6 Comanche
#1
CF Veteran
Thread Starter
Join Date: Jun 2009
Location: Michigan
Posts: 2,131
Received 288 Likes
on
238 Posts
Year: 1987 MJ, 1998 XJ, 1973 J2000, 89 waggy
Model: Comanche (MJ)
Engine: 4.0L H.O
Lets talk Ultimate! A Crew Cab 6x6 Comanche
How could anyone resist the idea of a crew cab MJ and why not add even more unicorn factor and throw an extra driven axle in there! Thats right an extra DRIVEN axle, not a dummy roller. Im talking 6wd!
This came up on one of my MJ Pages and had me asking so many questions. Unfortunately all we had was pictures like this and nothing really showing the driveline. Though i have my suspicions that this one isn't 6wd I would be determined to have functional 6wd on my build.
I have found a build thread for this Crewcab MJ and it is Phenomenal! Well documented in how the 2 halfs were mated together and he made a full door in the back! I've seen these builds where the left the factory wheel arched back doors from the XJ and it looks rather silly to me. My build would definitely incorporate the full rear doors.
So i have my ideas and before i lay them out let's hear yours. How would you build it? Love the idea hate the idea?
This came up on one of my MJ Pages and had me asking so many questions. Unfortunately all we had was pictures like this and nothing really showing the driveline. Though i have my suspicions that this one isn't 6wd I would be determined to have functional 6wd on my build.
I have found a build thread for this Crewcab MJ and it is Phenomenal! Well documented in how the 2 halfs were mated together and he made a full door in the back! I've seen these builds where the left the factory wheel arched back doors from the XJ and it looks rather silly to me. My build would definitely incorporate the full rear doors.
So i have my ideas and before i lay them out let's hear yours. How would you build it? Love the idea hate the idea?
#2
CF Veteran
I have toyed with the idea, and would like to do it on a stretched XJ someday. The tricky part is getting both rear axles to work. It takes some custom transfer case work or custom work on a pass through Ford 9" rear end
#3
CF Veteran
Thread Starter
Join Date: Jun 2009
Location: Michigan
Posts: 2,131
Received 288 Likes
on
238 Posts
Year: 1987 MJ, 1998 XJ, 1973 J2000, 89 waggy
Model: Comanche (MJ)
Engine: 4.0L H.O
So i've been rather obsessed with the thought of going for it and building one of these. Enough so, that i've listed one of my projects for sale for a couple reasons one mainly being to regain some work space but also to lighten my load on projects. This will also give me more dedicated time toward actually finishing the ones i currently have. Meanwhile collecting key parts/pieces to eventually stab together to create this unicorn.
MY idea would be to run a divorced tcase behind the stock 231 tcase via a short slip shaft and yoke. Making a crew cab MJ would give me enough room to sneak in a 2nd tcase, one that would have a dual output. The rear most axle would be driven out of the "normal" centered output on the divorced case(either setup as a piggy back mount from the middle axle or a carrier bearing setup just above the middle axle). Then the middle axle would be driven off the 2nd output from the divorced tcase. (dual output tcase driven from center and driver side.)
As far as axle choice i would keep the D30 front as they are reliable enough for my needs. In the rear i would go with Ford 8.8's, the offset pinion center could work in my favor to help with reducing compound angles and also keep me from having to make a custom axle with custom length axles shafts. There are some people out there who swap in their F8.8 and actually run a wheel spacer on just the one side to correct the pinion center of axle and eliminate the compound angle (also matching the stock D30's width in the process as they are a little narrower than the jeeps regular axles). As mentioned this could also work in my favor because i could then run the same thickness wheel spacer on the opposite side of the middle axles wheel end thus kicking it not only closer to its driven output but also farther out of the way of the rear axles driveshaft setup.
Tires and suspension would be kept very simple and practical using 33" tires and a 5-link coil sprung setup much like the Jeeps front suspension and the geometry would have less compounding. Straight forward upper and lower link on top and bottom of the axle tube running parallel to each other up to the frame. Track bar to keep the axle in center under the rear of this pig! While im sure its rolling through your head that this unicorn may not flex very well and your probably right. I would intend on wheeling this one very hard, more so and cool cruising rig. Sure there are sand dunes here in MI which would be fine but this would definitely not see the same abuse or weekends some of my other builds see.
You may now be questioning the dual rear axles mounting length? Prolly thinking that this will end up looking like a bus when its done? Well the short bed MJ's are 77" from front to back (this is the bed only) While the long bed MJ's are 91". Running both axles - 33" tires and a 4" gap between tires - giving a couple inches of wheel well in front of and behind - I would wind up with roughly 7" of actual bed steel on either side of the whole mess. I should clarify that i would limit myself to that 91" Long bed measurement so i could still use one of them old man toppers IF desired. If sourcing either a short bed to modify and stretch and a long bed donor MJ becomes too pricey or difficult i could always just build a spanking new straight line frame and toss a flat bed over the back. So all in all it may end up being roughly 3'~ longer than a long bed MJ.
MY idea would be to run a divorced tcase behind the stock 231 tcase via a short slip shaft and yoke. Making a crew cab MJ would give me enough room to sneak in a 2nd tcase, one that would have a dual output. The rear most axle would be driven out of the "normal" centered output on the divorced case(either setup as a piggy back mount from the middle axle or a carrier bearing setup just above the middle axle). Then the middle axle would be driven off the 2nd output from the divorced tcase. (dual output tcase driven from center and driver side.)
As far as axle choice i would keep the D30 front as they are reliable enough for my needs. In the rear i would go with Ford 8.8's, the offset pinion center could work in my favor to help with reducing compound angles and also keep me from having to make a custom axle with custom length axles shafts. There are some people out there who swap in their F8.8 and actually run a wheel spacer on just the one side to correct the pinion center of axle and eliminate the compound angle (also matching the stock D30's width in the process as they are a little narrower than the jeeps regular axles). As mentioned this could also work in my favor because i could then run the same thickness wheel spacer on the opposite side of the middle axles wheel end thus kicking it not only closer to its driven output but also farther out of the way of the rear axles driveshaft setup.
Tires and suspension would be kept very simple and practical using 33" tires and a 5-link coil sprung setup much like the Jeeps front suspension and the geometry would have less compounding. Straight forward upper and lower link on top and bottom of the axle tube running parallel to each other up to the frame. Track bar to keep the axle in center under the rear of this pig! While im sure its rolling through your head that this unicorn may not flex very well and your probably right. I would intend on wheeling this one very hard, more so and cool cruising rig. Sure there are sand dunes here in MI which would be fine but this would definitely not see the same abuse or weekends some of my other builds see.
You may now be questioning the dual rear axles mounting length? Prolly thinking that this will end up looking like a bus when its done? Well the short bed MJ's are 77" from front to back (this is the bed only) While the long bed MJ's are 91". Running both axles - 33" tires and a 4" gap between tires - giving a couple inches of wheel well in front of and behind - I would wind up with roughly 7" of actual bed steel on either side of the whole mess. I should clarify that i would limit myself to that 91" Long bed measurement so i could still use one of them old man toppers IF desired. If sourcing either a short bed to modify and stretch and a long bed donor MJ becomes too pricey or difficult i could always just build a spanking new straight line frame and toss a flat bed over the back. So all in all it may end up being roughly 3'~ longer than a long bed MJ.
#4
CF Veteran
This has been done in a Jeep before. Here is a pic of it and the drive train. The transfer case was made by combining a Dana 18 and 20 cases. All you need to do is machine a third hole for a shift rail for the front output. Then get an adapter from Advance Adapters for the older cases
#5
CF Veteran
Thread Starter
Join Date: Jun 2009
Location: Michigan
Posts: 2,131
Received 288 Likes
on
238 Posts
Year: 1987 MJ, 1998 XJ, 1973 J2000, 89 waggy
Model: Comanche (MJ)
Engine: 4.0L H.O
Im digging this back up as im taking a real stab at this soon. I acquired a free XJ and currently have both a disposable shortbed MJ and also still have just the rear section of an MJ cab to play with.
I realize the amount of work behind potentially ditching the unibody and building a custom frame but its a thought at the moment
I realize the amount of work behind potentially ditching the unibody and building a custom frame but its a thought at the moment
#7
CF Veteran
Join Date: Apr 2016
Location: Pasquotank, NC
Posts: 1,679
Likes: 0
Received 15 Likes
on
13 Posts
Year: 1990
Model: Cherokee
Engine: 4.0
SO.... other than uniqueness, what does a 6x6 bring to the table? Better traction off road? Or strictly load capacity? Not trying to be snarky, really curious.
Trending Topics
#8
CF Veteran
Thread Starter
Join Date: Jun 2009
Location: Michigan
Posts: 2,131
Received 288 Likes
on
238 Posts
Year: 1987 MJ, 1998 XJ, 1973 J2000, 89 waggy
Model: Comanche (MJ)
Engine: 4.0L H.O
I don't have a good answer for you. I guess the best i could say is at the very least it would be a cool conversation piece for other offroad jeep enthusiasts
Thread
Thread Starter
Forum
Replies
Last Post
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)