[MoparMurdoc]

So, I have an idea (like always), and I just wanted to see what you guys think. Since I'm swapping in 1 ton axles I'm going to have to get new driveshafts, and I've been planning to shorten the frame of the Power Wagon to get a shorter wheelbase sometime. So I thought "Hey, wouldn't it be cool to use the same driveshafts front and rear?" (accually got the idea form PJTPW's truck, Check it out). Having the same driveshafts front and rear would make it possible to only have to carry 1 spare driveshaft and 1 size of spare u-joint when doing extreme wheeling. Also, the front drive shaft is of the double cardan u-joint style (commonly called a CV driveshaft or a High Angle driveshaft). That would let me run a big suspension lift or raise the transfercase up 2-3" to increase my ground clearence. Sounds good, right?
Originally I wanted to shorten my truck 9" (from 115") to give it the same wheelbase as a ramcharger, but that dosn't really mater because I still need custom driveshafts for the 1 ton axles with bigger u-joints. I did some measuring and it looks like if I move the axle foward about 12", it'll be the perfect length to fit a front driveshaft back there. That would give me an ultra-short wheelbase of 103", which is like a Jeep Cherokee.
I might even be able to get front driveshafts from a 1 ton Dodge instead of big buck custom ones. I'd need a drive flange that would fit the back t-case output, I doubt the stock front one would fit, would it? So, it all seems like a cool idea, what do you guys think? There's a lot of theory to it, I'm hoping some of the technical guys can help me out here, tell me if its possible?

 

[Dodgeman]

Its possible, I have been thinking about that, the cardan joint part on the rear shaft anyway, I enjoy the benefit of the longer than jeep wheelbase when crawling where i go, but I want the flex of the cardan joint in the rear, My plan was to just remove the last flange where the front shaft bolts to the front output of the t case, and just clamp that U joint into the yoke on the rear output if theres room, I havent tried to fit it yet, but i think it would work, also I plan to extend the driveshaft for rear use some how

 

[Smokey]

If you don't mind the look of the rear wheels that far forward, it'll work.

I'd be more tempted to move the Tcase back a little and the rear axle forward a little, two custom shafts the same length, and a bit better angle on the front... In fact, same angles on front and rear...

 

[StandardByker88]

yeah, instead of moving the axle forward 12", try like 6" and the tcase back 6". but i dunno how you would do that much...

 

[MoparMurdoc]

Heres an idea (kinda a combo of the stuff u guys said): What if I move the front axle 3" foward, then shorten the frame in the rear by 10". That would give me equal shaft lengths and angles and everything, if I tucked up the t-case. However, I think having the front axle 3" foward would look real funny unless I had big tires. I'm probably gonna get some between 35 and 38", havn't really decided for sure.

 

[TheRamChargerMan]

You can't use the flange and just bolt the ujoint to it..it won't work. I also don't think the splines are the same for the fornt and rear d/s's at the tcase.

This is what I was told anyway by Denny's when they made my driveshafts.

 

[MoparMurdoc]

Hey, I knew Denny's made omlettes and pancakes and stuff, didn't know they did driveshafts too! heh

 

[PJTPW]

I definately wouldn't shorten it to 103". There are two ways to climb vertical stuff well:

1.) Light weight, or
2.) Wheel base

Since our Dodges will never be light weight, having a little wheel base helps out a lot. I'm at 125" and I'll admit it's a bit much for most stuff. But for Moab and other super vertical stuff it's the set up IMO, unless you weigh 3,100 lbs.

But with running that much wheel base, I needed the two piece shaft for a really big break over angle. Mainly for rock ledges.

I mainly went with the two piece rear because I wanted the big break over. Depending on what you do, rocks or mud, I might just suggest sticking with a one piece rear. Especially with 115" of wheel base.

I don't want to discourage you on running the two piece rear, but it was more work than normal, and requires CVs with some large angular capability.

Things you'll run into that could be a problem include:

Front and rear output splines are different on most T-cases. I put a big 32 spline output in my 205 so I could run the same flage front and rear.

If you raise the t-case(s) up flat you'll need at least a 32* capable CV if you've got a flexible suspension. Maybe more.

And you'll have to cut the majority of the center of the cab out. You pretty much ruin the structural integrity of the cab truth be known. I know I had to reinforce mine, and it still moves around too much.

Your rear pinion angle might be a bit much for extended freeway driving. I'm running 25* on the rear and overfill the 14 Bolt.

I would lay all this out on graph paper and look at how much break over you'll really pick up and then decide if it's worth it.

If you do decide to go with the two piece rear with matching shafts, I would move the front axle forward before getting shafts. You'll want to go big in the future even if you don't think you will. I wheeled with 32's for years, but eventually went to 44's.

You can get carrier bearings and short "midship shafts out of most longer wheel base Ford trucks. I would suggest this route for cost effectiveness. You could also get the rear shaft that goes to the axle and shorten it up and have the two piece rear for relatively little money. Might even want to pick up an extra couple of rear shafts, make another for the front out of one and carry a spare.

I don't know if you need a lot of wheel spin but a square tube driveshaft for the front could work well if you're not spinning a lot of RPMs and have a part time t-case. You can get virtually unlimited slip out of them, and make them relatively cheap.

I wouldn't worry about 1410's or anything that big at the axles. I had to replace my yokes so they would match and it was just as cheap to get them so I did. 1350's are plenty strong and 1310's are pretty tough as well. I never broke one of the small 1310ish U-joints even with 44's, but it was mostly in mud.

Good luck with it. If I can help let me know.

Ryan

 

[Evildriver-3]

Most of what PJTPW said is balls on right, if you move your tcase up with that cv you can forget all about any front suspension movement, just leave it alone this idea sucks, short wheel base does suck for climbing, go look at a hill climb truck they are far from short, this is a bad idea and not a good 1 either, the shorter the shafts the more movement they need, when you have a short line on an angle the angle varries greater than it would if it was long

 

[MoparMurdoc]

Well, I mean, long wheel base has advantages and disadvantages. For hill climbs and stuff like Moab I guess it'd be good, but in the trails up in MA, things get pretty tight, and a long wheelbase dosn't help. Then again, If I could tuck the t-case up like PJTPW did, then at least the breakover ground clearence would be ok. What about moving the back axle foward 10", and the front foward 3"? That makes for equal length driveshafts and a 109" wheelbase, shorter then a pickup but longer then an RC? Because the shorter wheelbase is one advantage, then the fact that the driveshafts match, then the fact that the breakover would be pretty good, then the fact that moving the axle 3" foward would help the approach angle a bit too. It'd also put less angular stress on the front driveshaft if it was lengthened. But this is all theoretical. Don't know if I could just have the stock front one lengthened for this stuff either, it dosn't seem very capable with the angles. This would increase the rear angle but decrease the front angle.

 

[PJTPW]

Wheelbase is great for Moab, but I got my azz handed to me on some super steep, 65-70* stuff this weekend. And what did it? Two Toyota flat bed pickups on 36" TSLs and 35" Krawlers.

Guess weight wins over wheelbase.

My truck is about to go on a serious diet.

Turning radius does suck on my truck. The more I drive it, the more I realize that. It's been pretty apparent the last few times out on some tighter trails. And this is with 10" wheels and 4.75" of back spacing.

109 seems like it would be a good compromise.

The front shaft would probably handle the angle with the axle moved forward 3". You would have to take the CV apart and clearance grind it so you could get more angular movement out of it. I did this on my old shaft and ran it with 4" of lift with no problems for about a year.

More than anything else, moving the axle forward will allow you to run a bigger tire with less cutting. But there are things to watch out for with this. The main one I'm seeing on mine is that I can't run high steer arms with the tie rod above the springs in front of the axle because the drag link angles forward from left to right. The tie rod and drag link would hit. This can be solved, but it's more work to fix it a couple of different ways.

Also keep in mind if you're going with a Dana 60 in the front and did have a Dana 44, the pinion is longer on the 60. You might could get by with a driveshaft spacer off the 203 (if that's what you're running) (I've got one sitting in my garage) and not need to lengthen the driveshaft on the front. You might want to do some careful measuring and see what would be most easy.

And something else to keep in mind, if you move the axle forward 3" with 4" of lift, you'll have to modify the engine cradle for differential clearance because you'd probably hit it on up travel. I had to modify mine with 4" of lift and my axle forward 3".

Personally I'd just carry two spare shafts versus all the trouble you'll have to go through to make it work. My system has the "wow" factor when people look at it, but it's really more trouble than it's worth in many ways. I only did it because I relocated the axles, replaced both axles, t-cases, and driveshafts all at once.

But I do really like it. Guess you'll have to decide if it's worth it. It's a lot of work.

Ryan

 

[MoparMurdoc]

Yeah, I'd be doing this next winter anyways, the trucks probably gonna stay pretty mild this year, because I accually want to get it on the trail this summer. I'm sure it'd be a lot of work, but I'm already changing to D60 front D70 rear this year, and the main reasons I'd want to do it is for the extra clearence I'd get from raising the t-case and shortening the wheelbase, I just figured having the same size driveshaft and an approach angle increase would be handy.
But, if your right about using a front driveshaft spacer, then I'd really only need a custom rear driveshaft.
However, the differential/engine clearence sounds like a problem, I'd probably be doing 4" or less lift, so I think less would just make it more of a concern.

 

[Sam Simpson]

why not just use a divorced tcase (if not already mentioned) to acheive your equal driveshafts. I think it should work on a powerwagon.

Also, the front and rear driveshafts on a stock RC have the same ujoints, even inside the cv for the front shaft. I have used a cut down rear shaft as the front shaft, cv-less since I had 10" of lift. I just pulled the CV apart and only used the part that bolted to the tcase, then set a ujoint in it. The two free ends of the ujoint where strapped into the driveshaft. So if I could use a rear driveshaft in the front, then you can use the front in the rear. You just have to pull the flange that bolts to the tcase output on the front.

 

[MoPaR MaNiaC 79RC]

Whats the deal with divorced t-cases? I don't really know the differnce, but i always hear about em. They have a u joint betwene the trans and t-case?

 

[Evildriver-3]

They aren't attached to the trans, there divorced from the trans and use another shaft to connect to the trans

 

[MoPaR MaNiaC 79RC]

How long is the middle shaft, usually?

 

[Evildriver-3]

16 or 18 inches i think if i remember correctly, usually found in crew cabs and club cabs