How much power can our differentials take?

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How much power can our differentials take?

Postby Begle1 » Sun Feb 25, 2007 12:12 am

I've never heard of exploding axles in trucks that aren't hooked to sleds.

So, for an unloaded truck, how much power do you get to run through your stock axle before you reach the danger zone?


And by the way, which trucks have which axles? Dana 70's for manuals and 71's for automatics, with a Dana 80-70 hybrid becoming available with the 2nd gen in '94?
1990 D-250 Regular Cab: Tweaked injection pump, built transmission, a cataclysmic charlie foxtrot of electronics, the most intense street-ran water injection system in the country, and some more unique stuff.
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Postby RumbleFish » Sun Feb 25, 2007 7:27 am

D70 - 1st gen w/3.54 & 4.10, 2nd gen 2500 automatic
D71 - 1st gen w/3.07
D80 - 2nd gen 2500 manual, all 3500

FWIW, I grenaded the 70 in my truck, and the only thing I had done to it was get rid of the muffler. I hadn't touched the pump. The roll pin that holds the carrier shaft broke, which allowed the carrier shaft to slide out and hit the inside of the housing. It trashed pretty much everything inside except the axles and the wheel bearings.
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Postby wannadiesel » Sun Feb 25, 2007 8:39 am

Stomp has blown up a couple D70's. He's working on destroying a D80 now.
'93 D350 LE Club Cab dually, Getrag, 3.54 Pow-R-Lok with: DPS EDM's, HTT Stage IV/14wg, Con-FE, Snow Stage 2 water/meth, custom fuel pin, Walbro secondary fuel system.

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Postby KTA » Sun Feb 25, 2007 10:33 am

In the 70 the weakest link is the pinion. I sheared mine off on the dragstrip when I was running 480rwhp and 1100 torque. Then I put the Dana 80 in and blew the spider gears out the back cover with it, so I put an ARB in and a few runs later twisted off an axle shaft. So I put a set of MOSER aka POS axles in and twisted both of them off the first pass. I now have the axle and hub kit from Haisleys and no more problems. :twisted:
Fleet of Junk: 1989 D350 627rwhp 1300 tq B-1/Hx60 twins, KTA pump/injectors, ported head, BIG fuel supply. 13.75@ 109.5mph 1/4: 1992 W350 Cab-chasis, 1993 W350 ext cab cust.370 inj Hx40/16cm 290rwhp hydroboost brakes,1984 D350 crew-cab another project.
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Postby Begle1 » Sun Feb 25, 2007 10:52 am

KTA wrote:In the 70 the weakest link is the pinion. I sheared mine off on the dragstrip when I was running 480rwhp and 1100 torque. Then I put the Dana 80 in and blew the spider gears out the back cover with it, so I put an ARB in and a few runs later twisted off an axle shaft. So I put a set of MOSER aka POS axles in and twisted both of them off the first pass. I now have the axle and hub kit from Haisleys and no more problems. :twisted:


:shock: What kind of launches are you doing to have that sort of luck? :shock:


What axle is the Haisley kit based on? What sort of rear end gears? Would you mind if I inquired the approximate wallet damage?

I really like my 3.07's, but they seem to be made of unobtanium and, if they couldn't stand to the power levels I want, I could probably sell them for a good chunk of change towards something heavier... If I installed my governor spring then I wouldn't rely on the low gears to get over 60 MPH, either. :(
1990 D-250 Regular Cab: Tweaked injection pump, built transmission, a cataclysmic charlie foxtrot of electronics, the most intense street-ran water injection system in the country, and some more unique stuff.
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Postby KTA » Sun Feb 25, 2007 10:55 pm

My Dana 70 was 3.54 geared and my Dana 80 is 3.31. Those launches were second gear about 1600rpm side step clutch. I culd usually nail a .00x light on the tree like that and in my single charger days I would run about a 2.3-2.5sec 60 foot. The haisley axles are custom made axles with drive plates, in other words the axles are splined both ends. My set came from the experimental days of that product and I have no idea what they cost now. If you dont apply the power like an idiot, IE drag racing, burnouts, sled pulling, you shouldn't have any problems with that stuff. I never broke anything in my drivetrain just driving around or making rolling power blasts. :twisted:
Fleet of Junk: 1989 D350 627rwhp 1300 tq B-1/Hx60 twins, KTA pump/injectors, ported head, BIG fuel supply. 13.75@ 109.5mph 1/4: 1992 W350 Cab-chasis, 1993 W350 ext cab cust.370 inj Hx40/16cm 290rwhp hydroboost brakes,1984 D350 crew-cab another project.
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Postby Begle1 » Sun Feb 25, 2007 11:33 pm

Well, DUDE, what good is having power if you can't apply it like an idiot?

Can 3.31's fit in any Dana 80? I've never heard of 3.31's...
1990 D-250 Regular Cab: Tweaked injection pump, built transmission, a cataclysmic charlie foxtrot of electronics, the most intense street-ran water injection system in the country, and some more unique stuff.
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Postby KTA » Mon Feb 26, 2007 6:25 am

You can pass anything you want. 8) They are stock Dana 80 gears.
Fleet of Junk: 1989 D350 627rwhp 1300 tq B-1/Hx60 twins, KTA pump/injectors, ported head, BIG fuel supply. 13.75@ 109.5mph 1/4: 1992 W350 Cab-chasis, 1993 W350 ext cab cust.370 inj Hx40/16cm 290rwhp hydroboost brakes,1984 D350 crew-cab another project.
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