Daveinet
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Update. I was talking to Jantz Engineering about buying girdles and discovered I'm not really addressing the root cause. When the gear broke, it broke the center out of the gear. That means the gears were perfectly aligned before it broke. That also means that the bearing and carrier were just fine before the gear broke. So the conclusion that prior to my hard downshift, the diff was perfectly fine. The gear just broke as a result of brute force, not a worn diff. I have a call into the local shop, they already bought the parts and were going to assemble it today, but I've done nothing to address the root cause. I've heard there is a such thing as Super 70 gears, that may fit into that case. Don't know how I can get the local shop to return the gears and if they will even consider putting larger gears in it, but I've got to do something.
Dave
The Flying Fortress
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'83 Revcon Prince 31' FWD
502 w/Howell/GM 16197427 ECM/Edelbrock MPFI,Thorley's & Magnaflows,
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FEDowner
Simi Valley Ca.
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Get some hardened gears and have them Cyrogenically softened.sound weird but it works and is not too expensive. Us drag racers do it all the time. There are lots of places that make rear end housings.
'06 Damon Challenger, Nostalgia Dragster & 28ft trailer,
Calpurnia (born 12-20-06)daughter of Traiano & Jasmine,
At the Rainbow Bridge Sonia 8-30-06 our 1st Neopolitan Mastiff
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Jarlaxle
New England
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Might be worth calling up Dynatrac or Currie...your use does not BEGIN to match what I have seen their axles hold up to! (1000HP big-blocks and 48" mud paddles come to mind!)
And I wonder if a high-pinion Dana 60 might work better than your Dana 70...a standard-rotation R&P loses, IIRC, about 35% of its strength running backwards.
John and Elizabeth (Liz), with 3 nutty cats
My beloved St. Bernard, Marm, lost him 1/2/12
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1992 International Genesis school bus conversion
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Daveinet
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Jarlaxle wrote:Might be worth calling up Dynatrac or Currie...your use does not BEGIN to match what I have seen their axles hold up to! (1000HP big-blocks and 48" mud paddles come to mind!)
And I wonder if a high-pinion Dana 60 might work better than your Dana 70...a standard-rotation R&P loses, IIRC, about 35% of its strength running backwards. I've gone back and forth on that mainly because looking at the rating chart from Dana, the 70BF (B series Front) is rated for 7000 peak, the high pinion 60 is 6000 peak. I understand the high pinion and reverse gears is for strength, but the BF is intended for front drive application, yet is still rated 7000 peak. There is a high pinion 70, but only available in very high ratios, so its not practical, even if I could make it fit. That is the real problem with getting anything custom. They modified the 70 to make it fit, so trying to get anything custom to fit means serious custom. I would not want to try it, unless they actually had the motorhome there, to prove fitment. The diff is in a confined area, so there are limits to what can be done. The 70HD and the high pinion 70 uses a bigger housing. Bigger or different housing won't fit.
I still think the best I can do is fit super 70 gears, and per the above comment, cryo treat them.
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travisc
Pacific NW
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Not sure if www.car-parts.com will help- but I have used it as a general guide to finding the places that participate - parts for my jeep
Winnebago Access 24V
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Daveinet
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Update:
Super 70 gears are the same size as standard 70 gears, we thought they might be bigger based on what a super 60 is, but not so. This means I am stuck with a stock rebuild and girdles. I am also sending the gears, bearings and carrier up to http://www.metal-wear.com/ to have it Cryo'd. It will not soften the gear as mentioned. Softening can happen if the process is not done properly. It will strengthen the gear, and make the surface harder for less wear. It will take another week before I get it back and try to make the larger cover fit.
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wildmanbaker
Kennewick, Washington
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Dave, the front drive axle may not have been of real good quality to begin with. Any of the after market suppliers have parts that stand up to allot of power in their "stock" form. Quality parts, along with a good setup, will probably last longer the the power plant.
Good luck
Wildman 
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cbigham
orange , CA
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Joined: 01/06/2005
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suggest you call these guys. If they don't have it they will know where it is inc. reverse cut.
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3875 Bancroft Drive, Spring Valley, CA 91977
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Daveinet
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The only reverse cut gears that exist for a 70 are way too high a ratio. The other problem is that reverse cut will not fit in a standard housing. It goes in a high pinion housing, which is half the advantage. High pinion housing is larger and won't fit. One of the things you run into is that the heaviest off road stuff is retro fitting a Dana 60, or they all go to Rockwells. For switching to 60 gears, they are considerably smaller around, which would not make sense to put in smaller gears.
wildmanbaker wrote:Dave, the front drive axle may not have been of real good quality to begin with. Any of the after market suppliers have parts that stand up to allot of power in their "stock" form. Quality parts, along with a good setup, will probably last longer the the power plant.Good luck The previous time I had it rebuilt, they used after market gears. This time they suggested using genuine Spicer parts, as they felt the OEM Spicer would be better than alternate brands, since their alternate brand is what broke.
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Scott & Jill
USA
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Sound expressive?
Life is too short; enjoy it the best way possible
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