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| | | Forums66 Topics128,115 Posts1,056,624 Members48,450 | | Most Online14,466 Apr 26th, 2026 | | AD Chevy Trucks Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
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For helping keep this great
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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Jun 2004 Posts: 66 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2004 Posts: 66 | What's the difference between a dana 70, 70hd, and a dana 80? I also wanted to know what I would have to do to get a 10 lug on 7.25" bolt circle for the above mentioned axles? I want the axle to be the wide dually axle because I want to build a fleetside dually pickup. | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | 70 is a 70, usually has 3.5" axle tubes 70HD is like a 70, uses the same gears, but with larger carrier bearings, 4" axle tubes, and spindles sized more like a Dana 80 80 is an 80, bigger then either 70 or 70HD. I've been told that the 10 lug hubs for a 70HD won't interchange with an 80. I think a search of this forum will reveal the details, I forget exactly. I've never seen a 70 with the 10 lug hubs. On a completely different note. You were looking for folding steps earlier, here they are: https://www.surpluscenter.com/item.asp?UID=2468021821383980&item=1-3297&catname=Grigg | | | | | Joined: Jun 2004 Posts: 66 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2004 Posts: 66 | So which would be the wider one or do I need to widen an axle housing and axles? I want this vehicle to handle a 478 GMC v-6, Fso-6406a trans, and pull around 22,000 on a gooseneck trailer. | | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | As far as I know (which is not very well) each can be had in two if not more different widths. Just take a tape measure with you on your searches.
A 3500HD with the 70HD or 80 is pretty narrow. Many P30 chassis with a 70HD are narrow. I expect some P30 chassis with 70HD or 80 are wide, look for one with tires out to about the edge of the body. | | | | | Joined: Oct 2003 Posts: 5,152 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Oct 2003 Posts: 5,152 | I have a 70-HD that is more than 70 inches wide. Might be 72 inches though I've not measured it in a couple of years. It is huge and it is heavy.
That rear came out from under a 70's GM Diesel dually, or at least that is what I was told by the guy I got it from. It is 8-lugs and has 4.11 gears.
I've also committed to trade it to someone else for something I want so if you want to ask questions about it do it soon, it should be gone in a few days.
1955 1st GMC Suburban | 1954 GMC 250 trailer puller project | 1954 GMC 250 Hydra-Matic | 1954 Chevy 3100 . 1947 Chevy COE | and more... It's true. I really don't do anything but browse the Internet looking for trouble... | | |
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