AMC Eagle Den Forum

The Shop => Altered Eagles => Topic started by: Nightpath on October 24, 2014, 05:04:38 PM

Title: Full swap driveshaft questions
Post by: Nightpath on October 24, 2014, 05:04:38 PM
I'm in the middle of my full drivetrain (4.0L / AW4 / NP242 / Chryser 8.25) swap.

If anyone has done this with these components (or the NP231 as they are almost the same size), was there any driveshaft fitment issues , length wise, front or rear?

The AW4 is about 5" longer but the NP242 attached is shorter than the NP128. I have a feeling that the rear driveshaft will be fine, but the front I'm not so sure about. With the AW4 sitting back close to 5" back, can the stock from driveshaft still be used?

Took these fresh today, HOT off the presses for my Eaglemaniacs :)

(http://i85.photobucket.com/albums/k78/nightpath/1986%20AMC%20Eagle/ae02bfee-c957-4d7a-8c66-159b4031d8e3_zps062e7b1d.jpg)
Title: Re: Full swap driveshaft questions
Post by: Nightpath on October 26, 2014, 09:20:52 AM
Anyone?
Title: Re: Full swap driveshaft questions
Post by: recomer on October 26, 2014, 10:04:47 AM
I haven't done any swaps like this with my Eagle so I can't give you any assistance on the driveshaft issue. That being said, should I swap out the transfer case on mine, the 242 seems the only option here. The 242 has the full time four wheel drive option where the 231 does not.  Would be a step back in my opinion.
Title: Re: Full swap driveshaft questions
Post by: Nightpath on October 26, 2014, 11:27:08 AM
Yeah, that's what I'm putting in it. The stock drivetrain that I pulled from the XJ had the 231 on it, to me putting that in would be sacrilege. 242 is the only way to go...but since I had all 3 sitting there I thought I'd do a side by side comparison for the Den.

The 231 is less thick than the 242, but the 242 is about 1" or so shorter than the 231. The differences can be seen though, I'd say on the 242 the yolk for the front driveshaft sits closer to the front of the vehicle and the rear ds yolk is set back a bit. I'm hoping that the difference in the transmission length (5") isn't going to be too much of a problem.
Title: Re: Full swap driveshaft questions
Post by: eaglefreek on October 26, 2014, 04:01:21 PM
My driveshaft with the swap measures 37" from center line of u joints. I measured a stock Eagle shaft totally collapsed and it was 40".
Title: Re: Full swap driveshaft questions
Post by: Nightpath on October 26, 2014, 08:07:00 PM
So will the stock Eagle rear driveshaft fit? I do still have the XJ driveshaft.

Any info on the front driveshaft?
Title: Re: Full swap driveshaft questions
Post by: eaglefreek on October 26, 2014, 10:45:44 PM
As I mentioned in your other thread, the rear might fit if you do a SYE, but I have no way to figure that out for you. The stock 4x4 XJ rear shaft is too short, you can have the 4x4 one made longer, but it would be cheaper to use a XJ or ZJ  2wd driveshaft and have it shortened. I had to have the front shaft made longer. I'm back at the hotel and don't nave a measuring tape with me. I'll ask one of the maintenance guys if I can borrow one tomorrow. But, I wouldn't have them made to my measurements, every installation will be a little different. You'll need to get everything installed and then get your measurements for you shafts.
Title: Re: Full swap driveshaft questions
Post by: Nightpath on October 27, 2014, 07:10:54 AM
That's what I kind of figured.

I'm using a 8.25 in the rear and still have my XJ rear driveshaft so I think I'll be good there.

The front I might leave the driveshaft off since my 3.55 axle I have has a few problems. Drive as a 2wd car until I get it rebuilt and it'll give time to measure and build a front driveshaft.

Been burning the candle hard at both ends being in the Canadian Forces with this ISIS crap and doing the build. Things are hazy.
Title: Re: Full swap driveshaft questions
Post by: carnuck on October 27, 2014, 07:21:43 PM
Max98059 swears he used the XJ rear shaft when we swapped the Eagle and XJ drivetrain we put in SOTE, but I know it was a 2 piece double cardan shaft from the front of an FSJ that I cut the double yoke from and put on a slip yoke with a hose clamp on the slip joint to keep the length right. That was 4.2L (Spirit with Eagle oil pan), AW4/NP242 (21 spline from an '89 XJ) and XJ D35 rear. For the front we used what I think was an Eagle shaft with the yoke from the NP129 which was shallower.
Title: Re: Full swap driveshaft questions
Post by: amchornet on October 31, 2014, 07:07:07 AM
I havent done this swap yet either but if I ever have trouble with the trans/diffs or 4x4 case you bet I will. So I will be watching your progress! Were you going to just get matching gears installed in your front diff housing when you get to that? Is the jeep diff the same width as an eagle? Everything I have read the drive shafts need to be adjusted in length....most of the time. I believe it all depends weather its an sx/sedan or wagon the combo goes into. Best of luck. :occasion14: