Doubler in an cherokee XJ

88jeepster

88jeepster

Jesus, Jannette & Jeeps for Life!
Banned
Joined
Feb 16, 2012
Location
Boone, NC
alright guys, just finished installing the 'doubler' 231/231 fyi and need some advise on cross member, linkages, reinforcement and such.
any advise on this stuff would be great before i go out to try/test out this weekend or so
 
Last edited by a moderator:
231/20, .......... naw,,,,,, just picking. I have thought about that though. I am curious as to the input you get. Might have to do the 231/231 myself. Just off the top of my head... A slider tied into the pinch seam & uni body frame section with at least a piece of angle on 2 sides would give a fairly stout cross member support. Just the typical beef things up & spread the load train of thought. disclaimer, I am not an ORV guru, but think I know a lot when under the influence of alcohol.
 
yeah i was just trying to use up one the the 2 extra jeep crossmembers i have layin around, the one that came off 99grand cherokee is really stout crossmember so i was trying to use that one with a new trans mount somehow, ill let you know what i come up with
 
be aware if you do the doubler, youll have to cut the floor board pretty good and you loose the right rear mount of your driver seat and have to raise it up a little but it works. im sure theres neater ways to do it but for a toy, i just did it to fit but thats also with the second case being clocked one degree for a bolt to clear, so if you didn't clock it at all you might be ok.
 
I can't help with your question but hats for for getting in there and going after it regardless of setup.
I have a question too. What is the easiest doubler to fit/setup and or which one provides the biggest bang per buck.
 
** I have edited the original post so as NOT to have a repeat of a former thread**
Please keep this tech!

I have not done the 231/231, but did do the 231/300. That said, I think you will find that this set up will have one draw back. The amount of torque you will have with the gearing will create a twist. That's where you will have issue if you don't prevent it from doing it. The cases on both of these are the weak spot. Both thin aluminum. NOT STRONG! You have to do everything to minimize the twist. From the engine back, so as the same amount of twist from the engine, to the rear case is the same. This will keep it from breaking. Throw out the idea of using a specific cross member(s) You will have to build your cross members to suit the situation.
I won't tell you how, because I never got it worked out myself, after several times breaking my 231 case, I gave up, sold it and bought an atlas 4 speed. The one option that was recommended by a member here Yager, was to build a rigid cage around the whole tranny/t case/t case set up, and then mount the set up to a cross member. Virtually making the whole set up act as one unit.
Not easy, but I do think necessary.
 
AX(J)15_tudor said:
I can't help with your question but hats for for getting in there and going after it regardless of setup.
I have a question too. What is the easiest doubler to fit/setup and or which one provides the biggest bang per buck.
Click to expand...
upnover is right, the 231/300 is better and stronger setup but cheaper is 231/231 cost me 1000 even for cases,kit, labor for my local builder to do it for me, NOW INSTALLING can be an ass with the floorboard. and so far just testing it in my driveway and up a few little climbs in the yard, LOL....it twists the whole drivers seat like 1.5" in the air when in drive and down about 1" when in reverse in double low. The crawl ratio is the coolest thing I've ever imagined in a Jeep and am really exited to trailer it somewhere like the Flats to really test out the limits but cost is affordable, have to tear up your floorboard and one seat mount, and looks like twistage is going to be an issue. so far I've reinforced the floor boards with more metal totally welded in and I'm thinking of welding in a second factory crossmember to stiffen the frame too.
 
so far from playing around with the doubler as it sits right now with my axles and 38s at 25psi, when in double low and wheel spin at about 3800rpm, that's when things on that D30 start to feel funny if I'm turned at all but down to 7psi same hill while slick, not a single spin...barely touched the gas which makes since since i cut the hell out of them tires. so I started a build to finally look into bigger for the front, rear down the road, but right now I have to focus on getting that twisting as he mentined out of the equation. I'm driving it to Aaron's next week and have him fab me up something.
 
Second cross member with second transmission style mount to the rear TC.
 
drkelly said:
Second cross member with second transmission style mount to the rear TC.
Click to expand...
that's what I believe Aaron is going to do and then I heard doing small little rubber link mounts from the top will help too so I'm looking into some sway bar links to fab up for the top "hanging" mounts and with the second lower mount, I should be ok.
 
upnover said:
It didn't work for me. the 231 is so super thin the little bit of twist kept poping the front case.
Click to expand...
I'm hoping I have better luck since the AW4 will take most of the vibration crap to it and with extra mounts HOPE to work plus keep my foot off the skinny pedal too and not get those rpm too high. It doesn't feel that bad at crawling speeds but once i get into 3rd or D that's when it feels the most strain so if it don't move in 1st gear crawling through stuff, I'll have to back off I guess and go around!!!
 
88jeepster said:
...it twists the whole drivers seat like 1.5" in the air when in drive and down about 1" when in reverse in double low..
Click to expand...

The 'double' low gearing puts a lot of strain on your engine mounts. You may need to upgrade to some HD aftermarket pieces.
 
I heard about that setup and it works. To the best of my knowledge from this build, anything will bolt onto a 231 adapter if splines and bolt pattern are the same. so 231 is 23 spline,91 and newer, so any 23 spline with that bolt pattern should work to my understanding. Don't hold me to that but I think. the benefit of that setup you're talking about is your ratio in double low would be way higher so on a real deal rock crawler, yeah that would be a huge difference but I'm very pleased with the price and ratio of my set up with 231s.
 
Back
Top