dana 70 or 14 bolt

hello, i am new to this site and in desperate need of help. i have a chance to pick up either a Dana 70 or a 14 Bolt FF. Both a at a great price and with good ratios. My questiosn is which i dont know much about the dana other than it is heavy duty. Does any body know anything about the D70 and which would you chose.  

both axles i would say are equally strong but ive heard there are more gearing and differential chocies and support for the dana 70 than the 14 bolt ff...... both are great axles either way and if your just planning on a detroit locker and gear up to 5:13 than the 14 bolt is just fine  
solid axle chevys cant be beat
78 K5: 350 V8,700r4,np208, 8 lug D44 4:88, 14 bolt 10.5 4:88 with detroit locker and 35 inc parenelli jones dirt grip tires

a 14 bolt is a little easier to set up. it has threaded adjusters instead of shims. and it has a pinion support piolet bearing. other than that they are both pretty good  
[X] Give Er Hell [X]

They both have strengths and weaknesses when compared with each other.  The D70 has 35 splined, 1-1/2" axleshafts where the 14 bolt only has 33 splined shafts.  The D70 uses shims for proper backlash where the 14 bolt uses adjusters that are WAY easier to set up.  The D70 uses 2 pinion support bearings where the 14 bolt uses 3 like the Ford 9".  In my opinion, the 14 bolt is the better axle for off roading, especially if you want to put a Detroit in it.  The 14 bolt is the cheapest (least expensive) unit that Detroit makes because the stock carrier is so strong, they re-use it.  They don't do that with any other axle, to my knowledge.  

14 bolt... for sure   strong strong strong  ..  
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Strength before Comfort..
1991 V2500 Suburban 4x4 5.7 14 bolt 4" up 35" BFGs 4:88's manual lock
Built 'OldSchool Chevy Tuff!!'

oh yeah i forgot to mention the ease of setup on the 14 bolt...... when i just recently installed the gears, the 14 bolt was way easier to set up than the front dana 44....... and yeah the detroit locker i put in alos used the stock carrier so that was also cheaper and easier........ the only real prob with the 14 bolt is the ground clearance as compared to other axles but that can be solved  
solid axle chevys cant be beat
78 K5: 350 V8,700r4,np208, 8 lug D44 4:88, 14 bolt 10.5 4:88 with detroit locker and 35 inc parenelli jones dirt grip tires

hey, i am doing a gear swap soon (3:73s > 4:88s). they want about 1,450 for front and rear. (i dont really think thats too bad *** i know that the gears have to be 500+ dollars. they will do the seals and wheel bearings too but, that hurts the budget still. how hard is it to do myself? i know it has to be perfect or else it will blow and i have to start over but, is it really that bad?  
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Strength before Comfort..
1991 V2500 Suburban 4x4 5.7 14 bolt 4" up 35" BFGs 4:88's manual lock
Built 'OldSchool Chevy Tuff!!'

RCG, it really depends on what axles you're running.  For a Corporate 14 bolt, the hardest part is setting the proper pinion depth, because that is based on shims.  The backlash is a no brainer because of the carrier adjuster nuts inside the housing.  Also, if your 14 bolt uses a crush sleeve around the pinion before the pinion nut, then that will be a pretty precise thing as well.  Dana axles, on the other hand, are a real PITA!  Everything is done with shims, backlash and pinion depth.  Sometimes you even need a case spreader just to get the old gears and carrier out.  If you are set on trying this out yourself, I have a couple of tips for you, as well as tools you will need.

Bearing seperator
Bearing heater/hydraulic press
Dial indicator with screw-on or a magnetic base
Torque wrench
Die Grinder

Now, after you get the Dana axle all tore down, make note of how much shim came off each side of the carrier as well as the pinion to give you a rough baseline to get you in the ballpark for setup on the new stuff.  Secondly, take the old bearings off the carrier and pinion and hog out the inside races a little bit with the die grinder.  This way they will slip on and off easy because most likely you will not have the proper backlash and pinion depth on your first try.  This will alow you to get the bearings on and off without having to use the seperator and heater/press every time.  Just prepare yourself for some very precision work and don't get frustrated.  I would also maybe try to find a book on setting up gears and differentials for some other tips.  If you have some good mechanical aptitude, you should be able to pull it off as long as you don't get frustrated and rush the job and half-ass it.  Good luck!  

man oh man, great advise. i really want to give it a try.. i dont want to kill everything i work for though. i have a friend who gave it a shot and blew it up a couple of times. then, he said 'f it' and took it in for a thousand bucks an axle. i guess learning can be expensive but, we have got to do it from time to time.  
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Strength before Comfort..
1991 V2500 Suburban 4x4 5.7 14 bolt 4" up 35" BFGs 4:88's manual lock
Built 'OldSchool Chevy Tuff!!'

Hey, I bet you that those of us who don't set gears up for a living, can all recount the first set of gears we did and how scared we were when we did it.  I know I can!  We all go through it man, so give it a try.  1 Thing I forgot to mention though.  When you hog out the bearing races with the die grinder, make sure you only do that to the OLD bearings (lol).  When you get the proper backlash and tooth pattern, yank those old ones back off and press the new ones on.  If you don't have a bearing heater or access/use of a press, then put the carrier in the freezer for a while, and put the bearings in the oven for a while (or heat them up with a torch).  Not super hot, maybe 3-400 degrees.  This will expand the bearings and shrink the carrier housing.  Just put the carrier in the freezer for a couple of hours though, not overnite.  You don't actually want it to freeze, otherwise when the hot bearings touch the shaft it may crack.  

Randys Ring and Pinion sell books on setting up rears I think it's around $30. Go for it!!