C30 diffs and wheel studs
 

Greetings.
I am building a bit of a hotrod chrvy truck on a 1977 chevy c30 chassis.

My c30 originally had a GM 14 bolt which i would like to change to a dana70 for a wider track

I believe c30s came with dana70 diffs. I have notice my dana70 has 9/16 wheel studs and left hand threaded nuts on 1 side. Does that mean that c30s from factory had different size wheel studs and nuts front to back?

Re: C30 diffs and wheel studs
 

Wheel studs are supposed to match front to rear. Left hand threaded studs would indicate a dodge or international rear axle unless it is a foreign thing. How wide of a diff are you trying to get? Most of the the rear axles-- beit a 14 bolt or Dana are usually the same width unless you get into the cab n chassis rears (which had the same housing--just a different hub) or the pick-up dually which was a Dana 70hd that had a width of about 72'' wms. GM did use a Dana 70 in some of the trucks but were the same width as the 14b

Re: C30 diffs and wheel studs
 

Hi kwmech, thank you for for info.

Yes mine is an australian GM 14 bolt from a cab+chassis c30 which i believe is the c20 diff with dually hubs.
Its alittle too narrow at 62" wmf to squeeze a 4 link between the outside rails and wheels i am running.

I am told this dana70 is from an F350. Its 65" wmf. Perhaps my best bet is to press in new wheel studs.

We dont have alot of C chassis stuff here in Australia and fewer experts so im very open to information and opinions on options from you guys.

Re: C30 diffs and wheel studs
 

Wondering if there is a way of widening my 14 bolt? Bigger hubs? Maybe a disc brake conversion thatsl changes the width?

Re: C30 diffs and wheel studs
 

If you use hubs from a single wheel instead of the dually hubs that will bring the WMS outward and still be able to use the same shafts

Re: C30 diffs and wheel studs
 

I need the long hubs. I am running dually alcoas.

Re: C30 diffs and wheel studs
 

I have a friend who bought a C20 converted to a dually so I know someone used to make a kit that converted the 14 bolt to use the dually wheels.

Maybe try these guys and see what they use to get the wider tires on the back.

/www.gsimfab.com/73-91-c30-dually-chassis-_8_4283_8893.html