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14 bolt ff 6 lug?
- Thread starter evilhorde
- Start date
14 Bolt Full Floater lug options.
It seems this question gets asked at least once a week, so here is a synopsis of your options ordered by cost.
First a little background information that might help. GM offers two different “14 Bolt” rear axles, with the only similarities between the two being the number of bolts (14) on the cover plate. The 14 Bolt Semi-Floater has a 9.5 inch ring gear and shares no significant parts with its big brother. The GM Corporate 10.5 inch (ring gear diameter) 14 Bolt Full Floater, which we are concerned with here, has eight lugs on a six inch diameter circle. The 14bff hubs have approximately a 4.5 inch outside diameter. The GM six lug pattern is on a 5.5 inch diameter circle. Another common lug pattern is five lugs on a 5.5 inch diameter circle. The industry standard wheel center diameter (for five on five and a half and six on five and a half) is 4.25 inches. Obviously these wheels will not fit over a 14bff hub without modifying the hub or the wheel.
Option 1: Use eight lug to six lug wheel adaptors. There are several manufactures that offer these. Most are made from 6061 T6 Aluminum but at least one manufacture makes them from steel. Prices range from $100 to $200. You will need to have your hubs and drive axle flanges turned down to under 4.25 inches (4.23 is a good size) so that the wheels will fit over the hub. Or you could do the ghetto fab thing and grind out the wheel centers. You won’t be able to use any other wheels in a pinch though. You will also need to change the drive axle bolts, as the heads will be too big once the hub is turned down. I use 12 point shoulder bolts, which will fit and look trick.
Option 2: Modify your 14bff hubs and convert to disk brakes. You’ll need access to a lathe, mill and optionally a welder or a machinist that willing to work with you. I used this method to convert to five on five and a half, but six on five and a half is the same process. First turn the hub and drive axle flange down to 4.23 inches in diameter and face the wheel mounting flange surface. Next turn down the back of the wheel-mounting flange removing all of the webbing associated with the eight lug holes. At this point you can weld up the eight holes for best results or opt to leave them, but the new holes will touch at least one of the old holes. Put them back in the lathe and clean up the wheel-mounting surface where welded. Next you will need to index the hub in the mill and drill your lug pattern. I used 41/64 to accommodate 5/8 wheel studs. Again, you will need to change the drive axle bolts, as the heads will be too big once the hub is turned down and use 12 point shoulder bolts.
Option 3: Use aftermarket hubs. Grady's offers these 6061 T6 Aluminum hubs in several different lug patterns. At about $500 a pair they seem expensive, but all you have to do is assemble them, no machining. By the way, Grady’s used to use Option 2 before they started making these new hubs.
Options 2 and 3 will both require you to use brake rotors with the same lug pattern as your wheels and you may need to open up the center to fit over the hub.
I know I haven’t covered everything, but this should be a pretty good overview. I’d welcome anybody else’s comments if they have had experience with this conversion. Before someone says “Just by some buy some $30 eight lug wheels and…” save it, there are some very valid reasons for converting.
It seems this question gets asked at least once a week, so here is a synopsis of your options ordered by cost.
First a little background information that might help. GM offers two different “14 Bolt” rear axles, with the only similarities between the two being the number of bolts (14) on the cover plate. The 14 Bolt Semi-Floater has a 9.5 inch ring gear and shares no significant parts with its big brother. The GM Corporate 10.5 inch (ring gear diameter) 14 Bolt Full Floater, which we are concerned with here, has eight lugs on a six inch diameter circle. The 14bff hubs have approximately a 4.5 inch outside diameter. The GM six lug pattern is on a 5.5 inch diameter circle. Another common lug pattern is five lugs on a 5.5 inch diameter circle. The industry standard wheel center diameter (for five on five and a half and six on five and a half) is 4.25 inches. Obviously these wheels will not fit over a 14bff hub without modifying the hub or the wheel.
Option 1: Use eight lug to six lug wheel adaptors. There are several manufactures that offer these. Most are made from 6061 T6 Aluminum but at least one manufacture makes them from steel. Prices range from $100 to $200. You will need to have your hubs and drive axle flanges turned down to under 4.25 inches (4.23 is a good size) so that the wheels will fit over the hub. Or you could do the ghetto fab thing and grind out the wheel centers. You won’t be able to use any other wheels in a pinch though. You will also need to change the drive axle bolts, as the heads will be too big once the hub is turned down. I use 12 point shoulder bolts, which will fit and look trick.
Option 2: Modify your 14bff hubs and convert to disk brakes. You’ll need access to a lathe, mill and optionally a welder or a machinist that willing to work with you. I used this method to convert to five on five and a half, but six on five and a half is the same process. First turn the hub and drive axle flange down to 4.23 inches in diameter and face the wheel mounting flange surface. Next turn down the back of the wheel-mounting flange removing all of the webbing associated with the eight lug holes. At this point you can weld up the eight holes for best results or opt to leave them, but the new holes will touch at least one of the old holes. Put them back in the lathe and clean up the wheel-mounting surface where welded. Next you will need to index the hub in the mill and drill your lug pattern. I used 41/64 to accommodate 5/8 wheel studs. Again, you will need to change the drive axle bolts, as the heads will be too big once the hub is turned down and use 12 point shoulder bolts.
Option 3: Use aftermarket hubs. Grady's offers these 6061 T6 Aluminum hubs in several different lug patterns. At about $500 a pair they seem expensive, but all you have to do is assemble them, no machining. By the way, Grady’s used to use Option 2 before they started making these new hubs.
Options 2 and 3 will both require you to use brake rotors with the same lug pattern as your wheels and you may need to open up the center to fit over the hub.
I know I haven’t covered everything, but this should be a pretty good overview. I’d welcome anybody else’s comments if they have had experience with this conversion. Before someone says “Just by some buy some $30 eight lug wheels and…” save it, there are some very valid reasons for converting.
Re: 14 Bolt Full Floater lug options.
/forums/images/graemlins/waytogo.gif
we need push pin/sticky post RIGHT HERE /forums/images/graemlins/deal.gif
/forums/images/graemlins/waytogo.gif
we need push pin/sticky post RIGHT HERE /forums/images/graemlins/deal.gif
smprider112
1/2 ton status
ya I was kinda in the same boat...I had new wheels and didnt wanna buy another set...realizing the price of the wheel adaptor was about the cost of 2 wheels...figured it was a better idea to just get new wheels and sell the old ones. /forums/images/graemlins/thumb.gif
pauly383
Daddy383
Re: 14 Bolt Full Floater lug options.
[ QUOTE ]
Option 3: Use aftermarket hubs. Grady’s offers these 6061 T6 Aluminum hubs in several different lug patterns. At about $500 a pair they seem expensive, but all you have to do is assemble them, no machining. By the way, Grady’s used to use Option 2 before they started making these new hubs.
[/ QUOTE ]
Now that I know these are available , a FUTURE upgrade if I ever break my 12 bolt is not out of the question . Do you have a link to Grady's ? , if not I can find it .
Will hub covers , either stock/aftermarket chrome , fit over the 14bff hub ? /forums/images/graemlins/k5.gif
I am running 12 bolt til I break it though /forums/images/graemlins/thumb.gif
[ QUOTE ]
Option 3: Use aftermarket hubs. Grady’s offers these 6061 T6 Aluminum hubs in several different lug patterns. At about $500 a pair they seem expensive, but all you have to do is assemble them, no machining. By the way, Grady’s used to use Option 2 before they started making these new hubs.
[/ QUOTE ]
Now that I know these are available , a FUTURE upgrade if I ever break my 12 bolt is not out of the question . Do you have a link to Grady's ? , if not I can find it .
Will hub covers , either stock/aftermarket chrome , fit over the 14bff hub ? /forums/images/graemlins/k5.gif
I am running 12 bolt til I break it though /forums/images/graemlins/thumb.gif
Re: 14 Bolt Full Floater lug options.
[ QUOTE ]
Do you have a link to Grady's ? , if not I can find it .
[/ QUOTE ]
Link added to the original post.
[ QUOTE ]
Do you have a link to Grady's ? , if not I can find it .
[/ QUOTE ]
Link added to the original post.
pauly383
Daddy383
Re: 14 Bolt Full Floater lug options.
I clicked on thier Blazer project...........OMG that 1st gen tub on the custom frame with the flat belly is tits /forums/images/graemlins/waytogo.gif
I clicked on thier Blazer project...........OMG that 1st gen tub on the custom frame with the flat belly is tits /forums/images/graemlins/waytogo.gif
I like that 8 to 6 spacer /forums/images/graemlins/eek.gif /forums/images/graemlins/eek.gif
Like Baja said on #2, you will need to have the hug and axle flange turned down to 4.300"- 4.250" inch so the 6 lug rim center hole will fit.
The pic is the spacer I made for my 14-bolt. /forums/images/graemlins/hack.gif /forums/images/graemlins/weld.gif /forums/images/graemlins/grind.gif
Like Baja said on #2, you will need to have the hug and axle flange turned down to 4.300"- 4.250" inch so the 6 lug rim center hole will fit.
The pic is the spacer I made for my 14-bolt. /forums/images/graemlins/hack.gif /forums/images/graemlins/weld.gif /forums/images/graemlins/grind.gif
