For those that are considering welding spiders for drag racing... It's against NHRA rules to weld a rear end, in any class.

Paul

 

the opinions of someone that welded up his 14b in a heavy DD/trail rig chevy pickup

i was running 38s and DDing back and forth to college and wheeling every weekend

1: no reason to buy a spool if you got welding skills, it will be the same thing
2: provided great traction offroad
3: fun to drift in the rain and snow
4: tire scratch around corners wasnt as bad as i thought it would be
5: didnt notice excessive tire wear, but my tires get beat off-road alot so im used to tire wear

im not going to lie, it is not the most street friendly traction device, but then again a leaf sprung, solid axle, chevy pickup on 38s really isnt either
i sacrificed street manners to have the best off-road truck i could afford at the time

i am now driving a beater truck with the locker in the rear, to tell you the truth if i didnt get the locker for 50 bucks i would have just welded this one too

would i do it again?
for the same purpose (basically a wheeling rig that i was stuck DDing cause i couldnt afford 2 cars) the answer is yes
for my daily driver that was going to see dirty occasionally the answer is absolutly not

 

I don't think there is anything wrong with welding the dana 70 rear end. However you might want to consider replacing your straps with u-bolts for the U-joint.

When welding your diff, the most reliable way will be to make some plates to weld to the carrier rather than welding the spider gears to the carrier and to themselves. Although I have never personally had problems with welding the spiders to themselves, others have. The last diff I welded was a Sterling 10.25 axle, I used 7011 Rod at 225 amps. I welded a large bead in between every other tooth, this set up allows for a little bit of play in the wheels(so they don't bark as much), also if you don't like the welded gig all you have to do is replace the spider gears, rather then replacing the carrier and spider gears, which requires resetting the ring and pinion.

I have had a welded rear end in my Bronco for years, and never had a single problem with it.

 

I purchased my Detroit Locker for right around $420 bucks

I did come acrosss a full spool for a d60, only in gear ratios 4.56 and higher...$250 bucks

 

If your gonna drive it on the road, you'll be breaking the law. I've seen a couple done for messing around off road and the axle shafts broke on them.

 

Glad I don't live in your state! No such law here. As you have read in this thread there are many people driving around with welded diffs that have NOT broken. I have found that OFFROAD you are LESS likely to break an axleshaft on a welded diff than on an open diff as the load is spread equally across both shafts as opposed to one shaft being shock loaded and breaking.

Just out of curiosity, what axles were those that snapped and in what type of vehicle. I betting they would have snapped even if it wasn't welded.

 

I'll bet if you dug into it you might be surpirsed about legality. You can't modify a vehicle in a way that degrades safety on the road, you can only modify to enhance. You break traction going aroud the curb, you just created a skid whether you feel safe or not.

The axles were only car axles, one a 10 bolt, one a 9 inch. The 9 inch was a small block dragster (the axle was only temporary anyway). The other, the axle twisted and snapped, probably doing some bounceing. It's been a long time, a little hazey.
Edit; Just noticed you're in Canada, probably all set up there.

 

Somethings wrong with your Detroit locker is if drags tires around corners. It is a ratcheting diff and should release smoothly and instantly. The onlt time you should ever know it's there is if you jam on if while entering a corner and catch the ratchet just right, you will get a thunk.

 

I have a detroit locker in my dana 80. It is a locker for a 70 HD with the ring gear bolt holes drilled out larger to accomodate the larger bolts the 80 has. There is no scratching and scuffing around corners, regardless of speed or sharpness of the corner. It's easier to spin the inside tire during the corner, since these lockers only power that tire during a turn. The outside tire freewheels. I have not managed to break it yet; I destroyed the spider gears in two stock limited slip units. Lockers are available for any gear ratio for the 80-I'd assume the same is true for a 70 HD, since they're the same locker before the holes are drilled larger.

 

I put a limited slip in my truck and it's a real pain in the neck. After I get off the highway it grabbs and always scrubbs the inside tire. I wish I would have held out for a DT. They sure worked great on the race cars! I could have paid for a new one with all the equi-torque I have had to feed this pig to keep it from burning itself up!