Sourcing a Front Drive shaft from the Junk Yard

[skidoo_j]

Okay the lengths of the drive shafts can be obtained through dana spec sheets. But the information they list on their sheets are the collapsed lengths. According to the dana spec sheets the collapsed lengths roughly are 29" for manual and 30" for auto. What I'd like is the stock resting length. I've measured my flange to flange, but this number seems to only be relevant when building new as factory Drive shafts are listed by collapsed lengths.

 

So I'm trying to see if a drive shaft from an auto that's 1" longer is correct for my truck now. But because i never took my original yoke to yoke measurement prior to the lift I don't want to assume and waste money on a too long or too short shaft. I'm looking for the length from centerline cross at axle to centerline cross at transfercase with stock suspension, on a xj/mj with 4.0 manual and/or auto. I'm hoping if i have one of those measurements i can atleast determine how much i've changed my current length and if i need to look to another vehicle for a front shaft.

 

the only other way i can think of to get a good length would be to remove my front coils, and let the truck rest on the bump stops, measure center to center and subtract like 1/3" for rebound and then find a front shaft from the dana's factory chart that way. and then go find the vehicle in the JY.

 

Unless someone knows what the standard deduction from yoke to yoke to collapsed length is.

 

(yoke to yoke) - ?????? = (collapsed length )

[skidoo_j]

Would someone be willing to crawl under their stock rig with a 4.0 auto or manual and measure the front drive shaft. Just let me know from where to where you measured. It's important that the weight is on the truck. If there isn't enough room for you to get under it for a full yoke to yoke measurement you could measure how much of the shaft is exposed. I think even that would be helpful knowing what powertrain combo it has. I'm just looking for a point of reference. Thanks in advance.

[sinkrun]

I can try later to measure do you still need it? I did have a front shaft from a 4.0 auto laying around if I do I will sell it but the yoke is bad guy welded caps in place.

[skidoo_j]

I can try later to measure do you still need it? I did have a front shaft from a 4.0 auto laying around if I do I will sell it but the yoke is bad guy welded caps in place.

 

 

 

Yes i need the measurements. I'm going to try and source a driveshaft at my local yard. But they only give in store credit on a return.

 

My stock manual shaft is in there and works, but it's close to 2.5" of exposed shaft. I don't' have a ramp to see if the suspension stops before the shaft pulls apart, so i know the auto being longer would be better but if i can get one that's perfect i'd rather. Hence why i need a stock reference for the axles other than collapsed length.

[ParadiseMJ]

I just swapped in an AW4 for my manual. The combo of the 1992 AW4/231J is 2.25" longer than the 1988 BA-10/231AMC. Both transfer cases are the same exact length. I kept the shaft attached from the 1992 231J when I gleaned it from an XJ the yard, mostly because I was tired, fed-up and just too danged lazy to pull the four bolts from the t-case. Now the set up is perfect for the front. The collapsed length of the front shaft is 2.25" longer then the old set-up. The expanded length seems longer than 2.25" longer than the old expanded shaft.

 

What you need is a shaft from an XJ/MJ with the same tranny you are putting in. You should always measure yoke eye to yoke eye.

 

Other than the obvious, I need a rear shaft that is 2.25" shorter than the original rear shaft...the MJ's from this yard are almost non existent, the only MJ's I've found are LWB's (mine is a SWB). The local drive-line shop wants $250 to shorten the shaft, weld on a new yoke, balance it and do the 2 u-joints. Seems a little steep.

[skidoo_j]

I just swapped in an AW4 for my manual. The combo of the 1992 AW4/231J is 2.25" longer than the 1988 BA-10/231AMC. Both transfer cases are the same exact length. I kept the shaft attached from the 1992 231J when I gleaned it from an XJ the yard, mostly because I was tired, fed-up and just too danged lazy to pull the four bolts from the t-case. Now the set up is perfect for the front. The collapsed length of the front shaft is 2.25" longer then the old set-up. The expanded length seems longer than 2.25" longer than the old expanded shaft.

 

What you need is a shaft from an XJ/MJ with the same tranny you are putting in. You should always measure yoke eye to yoke eye.

 

Other than the obvious, I need a rear shaft that is 2.25" shorter than the original rear shaft...the MJ's from this yard are almost non existent, the only MJ's I've found are LWB's (mine is a SWB). The local drive-line shop wants $250 to shorten the shaft, weld on a new yoke, balance it and do the 2 u-joints. Seems a little steep.

 

 

I'm not changing my drive train. I've lifted the front about 4.5" plus i have adjustable control arms and I'm sure they're longer then stock to maintain the correct angles.

[ParadiseMJ]

I have 2 rigs

 

90 XJ AW4/231J (no sye) @3.5 lift with aftermarket LCA's. The LCA's are 1" longer than stock.

The front shaft at rest is 32.5" from axle yoke to t/c yoke. There is 2.5" of the skinny part of the shaft exposed, not all shiny part...just skinny part.

 

88 MJ AW4/231J (no sye). SUA BB lift 2". Stock control arms. Right now I have the old front shaft and the "new" shaft off the truck. Fully extended 34.5" from eye to eye of the very front and aft u-joint. The distance from the t/c yoke to the axle yoke (on the truck at rest) is 32.5". The new shaft is 30.5 compressed. The old shaft is 27.5" compressed.

 

Disclaimer: I just did this in the gravel in my driveway with my swimsuit and flip flops on after a couple beers, so measurments are ~~~close, but not caliper accurate.

[skidoo_j]

I have 2 rigs

 

90 XJ AW4/231J (no sye) @3.5 lift with aftermarket LCA's. The LCA's are 1" longer than stock.

The front shaft at rest is 32.5" from axle yoke to t/c yoke. There is 2.5" of the skinny part of the shaft exposed, not all shiny part...just skinny part.

 

88 MJ AW4/231J (no sye). SUA BB lift 2". Stock control arms. Right now I have the old front shaft and the "new" shaft off the truck. Fully extended 34.5" from eye to eye of the very front and aft u-joint. The distance from the t/c yoke to the axle yoke (on the truck at rest) is 32.5". The new shaft is 30.5 compressed. The old shaft is 27.5" compressed.

 

Disclaimer: I just did this in the gravel in my driveway with my swimsuit and flip flops on after a couple beers, so measurments are ~~~close, but not caliper accurate.

 

 

so both sets of measurements you are providing are altered suspensions? i'm conflicted on how your xj with 3.5" lift and 1" longer arms has the same t/c yoke to axle yoke measurement as 2" lift with stock arms. there should be close to an inch difference from the arms as the front of an xj and mj are identical and you listed both tranny and transfer as the same.

 

what is your "new" shaft from?

[ParadiseMJ]

The new shaft is from an XJ with no apparent lift, stock arms, AW4/231...jacked up at the yard.

 

I'm just reading what the tape measure said. The IMPORTANT measurement is the length of the tranny and t-case combination. That's what will dictate the length of the shaft...that's why the XJ with AW4/231 and MJ with AW4/231 are virtually identical, lifted or not. Unless you're lifting 5-6" that 1" at the CA is not going to make much difference.

 

The shaft does not move in and out all that much in motion in my experience.

 

Oh, and there's the disclaimer that I wrote at the bottom.