I have a set of J10 Dana 44s, I dont know if I want to use them. The matching front is a LP so it isnt that desireable. Should I spend the money and get a HP44 and 60 rear? The obviouse answer is yes. But... it is just more money going out. How much more ground clearance do you get out of a HP vs LP? The high pinion would be good for my current short wheel base...
Comments!
High pinion is good in the front due to the way the gears mesh...going forward with a High pinion front you're applying load to the stronger drive side of the gear teeth rather than the weaker coast side in a low pinion. The opposite is true for the rear. Wheelbase doesn't really make much difference in the front application as the front driveshaft is so much longer than the rear in this application. High pinion would be good for driveline angles in the rear axle but would suffer from the problem I mentioned above. Then again, the angle of the Jeep's powertrain causes the front driveline angle to suffer more because the t-case output for the front is actually angled UP, and a higher pinion helps relieve that angle. You don't get too much ground clearance advantage because the pinion should be angled up anyway and your diff cover mounting flange should be the lowest point of the axle.
I maintain that the front axle isn't seeing anything close to maximum load unless you're going in reverse...because weight distribution going forward pulls weight off of the front axle causing it to lose traction. Going uphill in reverse (Cory) or snatching someone out of a hole in reverse(narrow trail where it's hard to turn around), you'd benefit more from a low pinion axle up front because then you'd be applying maximum force to the front axle on the drive side of the gears.
There are two schools of thought on that and they're both right, you should just determine which option is best for you. Personally I'm going to go for a HP front axle because if someone's stuck bad enough that I'd break my ring gear pulling them out...I'll just winch them.
[edit] He beat me to it...
With the HP you'll drag the driveshaft on a whole lot less stuff because, obviously, it's not at the lowest point of the axle.
The other benefit, and probably more important to a lifted short wheelbase rig, is less driveshaft angle so it's less likely to bind with articulation and also less u-joint wear.
I swapped in Wagoneer D44's into the YJ I used to have, they were low pinion and I never had a problem with them, other than one busted front shaft. But that was due to some serious gear reduction and deep florida swamp mud. I had the jeep buried over the top of the 38's and I was in 4-lo (3.8 Atlas) 3rd gear (T-18) and stalled it. Started it up, tried second, smoked the centerforce clutch, tried first and pow!!! there went a front D44 shaft.
As for the low pinion, it never really mattered on my old YJ... never had a prob with the gears at all and I used to give that jeep hell.... 4.0L screamin at over 7K!!!! back before they had rev limiters.
I havnt decided if I am just going to buy a parts truck (F350/Bronco/What ever works) or buy a set from calico
I think I am leaning toward
HD44 /// 60R
I had a D44 in my JY out of a 77 FSJ Cherokee, I had no problem with it, I ran 38.5 swampers and never broke it. and it had a spool. I did move the front axle forward 2 inches useing waggy springs, But the stock driveshaft bolted right up. If your really worried about DS angles you could always do a cut and turn on the steering knuckles. In my opinion If I were you I would use the axles you already have, then spend the money you were going to spend on a new set of axles on some 4340 shafts for the Front axle. remmeber when you do the axle swap you are going t want to basicly go through the axles and re do them so your not swapping in junk. you want to re pack/ replace wheel berrings, locking hubs axle seals replace the brakes. do it right the first time...
What tire size are you going to run. 35" and under the lp 44's will be fine ( as long as you don,t try to jump the chena!). 36" fo bigger.
I want to get to a 38.5 at min. I might stay closer to a 35 until i get a new pull truck