Dana 70??

[Bagged Dually]

I figured out my truck has a DANA 70 for a rear end. Or at least from what I can tell and have read it's a DANA 70. Is this a good rear end?? I have almost no experience with DANA or chevy rear ends. About every axle I've ever built or cared to work on was a Ford 9".
The next question is were is the best place to get a new set of gears for the 70 that's under my truck?? I think it has 4:56's in it now and I'm needing to get closer to 3:55-3:73 for some better highway MPG.
Any thoughts??

 

[crazy4offroad]

It's comparable in specs to the GM 14 bolt full-floater, the main advantage is a wider gear selection than the 14 bolt. However the 14 bolt does have the support on the pinion like the 9" does but the D60/70 doesn't. Here's some info links...
http://pirate4x4.com/tech/billavista/PDFs/New Jun 2003/West Coast Diff Dana 70 catologue.pdf

http://pirate4x4.com/tech/billavista/D70/D70.htm

A lot of info here...
http://www.pirate4x4.com/forum/showthread.php?t=522333

 

[crazy4offroad]

Aside from the usual offerings from Summit and Jegs I've had good dealings with these guys for gears...
http://completeoffroad.com/c-65151-...r-dana70-70hd70u-dana-70-70hd70u-rp-sets.html

 

[Bagged Dually]

Thanks for the info crazy.

 

[HotRodPC]

Easy Kris, he gets pissy when you call him Crazy. We abbreviate him as C4. You know, like the explosive.... that's Crazy. He's fuggin Crazy, so just call him what you want and tell him I said you had permission.

Yep, I'd rock a D70. That's what I have in my 93 E350 box van. If I recall, it was Crew Cab Duallys, and Cab and Chassis that came with Big Blocks that got the D70's. Everything else was 14b FF. Most of us would prefer the 14b FF, but the D70 is certainly a very good rearend.

 

[bucket]

It was only the regular duallies that got the D70. The single wheel trucks and the cab&chassis trucks got the 14FF.

 

[HotRodPC]

Hmmm, that sorta makes sense to what I've seen but, I was told by a guy who rebuilds diffs and has a diff shop that bad info above. Goes to show, even the ones that oughta know, DON"T !!!

 

[bucket]

It kinda makes sense why GM did it that way. The single rear wheel and the c&c dually rear 14 bolts are basically the same housing. The c&c dually version has the hubs that move the wheels inboard some (same hubs as the dually D70). Then the dually D70 housing is much wider with bigger axle tubes.

BTW, dually axles are great to use if you want to run the H1 beadlock wheels. You can also use the SRW 14 bolt wheel hubs to make the wheel mounting surface about the same as the front.