you want to change your 5X5 bolt pattern on 73-87 disc to 5X4.75

[SCOTI]

Ahhh.... The numbers may not mean anything then (because of the different calipers). The set-up I have is OE S10 (11" rotors IIRC) w/OE rear emergency brake.

I have everything minus one rotor that my buddy mis-placed some where along the line. I'll try & grab a rotor & put it inside a wheel & measure from the wheel 'pad' to the inside rotor surface (right?).

[babyblueoval]

Originally Posted by SCOTI

I'll try & grab a rotor & put it inside a wheel & measure from the wheel 'pad' to the inside rotor surface (right?).

I just put the rotor hat down on the counter at the parts store and put a straight edge across the top. That is how I got the measurements and they are the same as stated in dimension info.

[SCOTI]

Originally Posted by babyblueoval

I just put the rotor hat down on the counter at the parts store and put a straight edge across the top. That is how I got the measurements and they are the same as stated in dimension info.

Will do.

[Grip]

If you want to convert to the car bolt pattern with factory parts, check with a wrecking yard that uses the Hollander Interchange books. I found that a 71-72 (if I remember the year correctly) G-10 van had the same upper and lower control arms as a C-10 truck, but used the car 4.75" bs rotors. Just score the spindles and for a bolt on conversion. I used this setup years ago to convert a 73 C-10 that I pro-streeted. I had 15X3.5" weld drag lites and they didn't make them in 5X5 bs.

[N2TRUX]

Welcome to the forum Grip we appreciate your input. I am a bit confused as I have always known all GM 1/2 ton trucks, vans, Burbs etc to have a 5x5 pattern.

[duceducenine]

not to confuse things too much....
i want to do the opposite camaro clip with 5 on 5 bolt pattern...[56 sub]
so all i need is 81+ 1" rotors using the camaro spindle? caliper?
or do i still need to use the truck caliper brakes?
can i put a truck spindle on the camaro a-arms w/ truck bj's?

[Grip]

Were there's a will there's a way...Try A&A mfg or UB machine. They both make weld in ball joint bushings that take common Moog ball joints. Just figure out the taper of your ball joint holes in the spindle and adapt your a-arms using the correct weld in ring.

[Grip]

Originally Posted by N2TRUX

Welcome to the forum Grip we appreciate your input. I am a bit confused as I have always known all GM 1/2 ton trucks, vans, Burbs etc to have a 5x5 pattern.

N2TRUX, Thanks for the welcome. I have been trolling for quite a while but finally decided to sign up. I grew up in a wrecking yard and it was 1987 when I last did the spindle swap. I called my dad who still runs the yard. He is going to look up the interchange # for me. I'll post it as soon as I hear back from him.

[Grip]

More info...I looked up the rotor for a 71 G-10 and found this on Napa's website:

It list a BUNCH of cars that are 4.75 bs as interchange

Rotor & Hub Assy - Front - Premium

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Front

Part: NB 4885542
Product Line: NAPA Brakes Rotors & Drums


List Price
Your Cost
Unit
:
:
:
93.16
62.80
Each

Qty

Features & Benefits
NAPA Premium Rotors Are Designed To Improve Stopping Distances, Minimize Brake Fade & Extend Pad & Rotor Life.; The Non-Directional Finish On NAPA Premium Rotors Reduces Noise & Braking Roughness.; Vane Configuration Reduces Temperatures & Improves Performance.

NAPA Brakes - Complete Line-Up

Attributes
# of Bolts : 5
Bolt Circle Diameter : 4.75"
Brake Rotor Diameter : 11.005"
Brake Rotor Discard Thickness : .965"
Brake Rotor Thickness New : 1.035"
Brake Rotor Type : Disc Brake Rotor & Hub
Height : 4.639"
Includes ABS Inner Sensor Ring : No
Includes Inner Bearing Cup : Yes
Includes Outer Bearing Cup : Yes
Maximum Lateral Runout : .004"
Mounting Type : Type J - 1 Piece Or Integral Hub & Rotor Assembly. Rotor & Hub Are Cast As A Single Unit. Wheel Studs Are Pressed Into The Rotor. See Diagram For More Information.
Vented / Solid : Vented

Warranty
12 Months or 12,000 Miles Whichever Occurs First

Warranty PDF

Material Safety Data Sheet (MSDS)
There is no MSDS for this item
Application Information: 1971 Chevrolet Truck G10/1500 1/2 Ton - Van
Per Car Qty: 2


Buyers Guide
Make Model Engine Year(s)
Buick Apollo 1975 - 1975
Buick Century 1973 - 1977
Buick Estate Wagon 1977 - 1978
Buick Lesabre 4.9 L 301 CID V8 1977 - 1978
Buick Lesabre 5.0 L 305 CID V8 1978 - 1978
Buick Lesabre 5.7 L 350 CID V8 1977 - 1978
Buick Lesabre 6.6 L 403 CID V8 1977 - 1978
Buick Regal 1973 - 1977
Buick Skylark 1975 - 1978
Cadillac Seville 1976 - 1976
Chevrolet Camaro 1970 - 1978
Chevrolet Caprice 1977 - 1978
Chevrolet Chevelle 1973 - 1973
Chevrolet Impala 1977 - 1978
Chevrolet Malibu 1973 - 1977
Chevrolet Monte Carlo 1973 - 1977
Chevrolet Nova 1975 - 1978
Chevrolet Truck El Camino 1973 - 1977
Chevrolet Truck G10/1500 1/2 Ton - Van 1971 - 1974
GMC Truck G1500 1/2 Ton - Van 1971 - 1974
GMC Truck Sprint 1973 - 1977
Oldsmobile Custom Cruiser 1977 - 1978
Oldsmobile Cutlass 1973 - 1977
Oldsmobile Delta 88 1977 - 1978
Oldsmobile Omega 1974 - 1978
Oldsmobile Vista Cruiser 1973 - 1975
Pontiac Bonneville 1977 - 1978
Pontiac Catalina 1977 - 1978
Pontiac Firebird 1970 - 1978
Pontiac Grand Am 1973 - 1975
Pontiac Grand LeMans 1975 - 1977
Pontiac Grand Prix 1973 - 1977
Pontiac GTO 1973 - 1973
Pontiac LeMans 1973 - 1977
Pontiac Parisienne 1977 - 1978
Pontiac Phoenix 1977 - 1978
Pontiac Ventura 1975 - 1977

[67 cst swb]

Originally Posted by Grip

If you want to convert to the car bolt pattern with factory parts, check with a wrecking yard that uses the Hollander Interchange books. I found that a 71-72 (if I remember the year correctly) G-10 van had the same upper and lower control arms as a C-10 truck, but used the car 4.75" bs rotors.

Well, you are correct on this... In addition to 71-72 there is also 73-74 G-10 vans. These (71-74 G-10) use the 70-78 camaro rotor & caliper. So, there are numerous outlets for big brake kits. Bear, SSBC, etc...
There is a difference between 71-72 & 73-74 G-10 Spindles, the outer tie rod mount is different. It's thicker where the taper of the outer tie rod goes thru the spindle.
As far as the outer tie rod ends used:
71-72 G-10 is same as 71-72 C-10
73-74 G-10 is same as 73-74 C-10
If I remember correctly, the 73-74 tie rod hole is thicker top to bottom.
In 75 G-10 went to 5 on 5 bolt pattern.

I have a set of each 1) 71-72 G-10 van spindles complete & 1) 73-74 G-10 van spindles complete.
My plan was to build a race truck style build and use cross drilled rotors that are commonly available for 70-78 camaro rotors as well as aftermarket race caliper (wilwood, strange, etc...) I actually had them mounted on a rolling frame for awhile with 15x7 ralley's for about a year before I changed my vision for the project.


P.S. yeah, I've worked in auto parts for 22 yrs, 5 yrs of that at NAPA, so, had lots of time to research stuff like this...
If you wanna talk using stock parts to come up with 6 on 5-1/5" disc brakes PM me, I've researched that as well, If I remember SCOTI helped me on that deal... that was awhile back, If SCOTI doesn't remember helping out, I'll take FULL credit for the research.... Just kidding SCOTI.
Bryan

[babyblueoval]

Originally Posted by Grip

Part: NB 4885542
Bolt Circle Diameter : 4.75"
Brake Rotor Diameter : 11.005"
Brake Rotor Discard Thickness : .965"
Brake Rotor Thickness New : 1.035"
Brake Rotor Type : Disc Brake Rotor & Hub
Height : 4.639"

67 swb cst,

What is the "Height" measurement in the specs measuring?
Is that how tall it is from rotor hat to the rear disc surface?
If it is, I'm trying to find something that's much closer to 2.335.

Thanks,
Jim

[N2TRUX]

Thanks for the info Grip and 67 cst swb. I always hear guys talking about running van rallies on the front because they are narrower than truck rallies. I had never heard that there were specific years that were not 5x5.

And now I know "the rest of the story"...

[gringoloco]

Originally Posted by duceducenine

not to confuse things too much....
i want to do the opposite camaro clip with 5 on 5 bolt pattern...[56 sub]
so all i need is 81+ 1" rotors using the camaro spindle? caliper?
or do i still need to use the truck caliper brakes?
can i put a truck spindle on the camaro a-arms w/ truck bj's?

Yes on the rotors. Use '81-up 1" truck rotors or B-body(Caprice)- same part number. They will still use the car calipers.

On the spindles- not that I'm aware of, but I seriously doubt it...

[67 cst swb]

Originally Posted by babyblueoval

67 swb cst,

What is the "Height" measurement in the specs measuring?
Is that how tall it is from rotor hat to the rear disc surface?
If it is, I'm trying to find something that's much closer to 2.335.

Thanks,
Jim

Sorry if I caused confusion...
The area that is thicker is where the outer tie rod mounts to the spindle (the tapered hole on the spindle). It is the same on the 73-74 G-10's as the 73-79 C-10. (I will edit this info above)
The 71-72 G-10 tie rod end mount thickness is the same as 71-72 C-10's.
BUT, 71-72 years are different than the 73-later (73-later being the thicker of the two)...
Check back to this thread later, as soon as I can I will get you the measurments.

[67 cst swb]

Originally Posted by duceducenine

not to confuse things too much....
i want to do the opposite camaro clip with 5 on 5 bolt pattern...[56 sub]
so all i need is 81+ 1" rotors using the camaro spindle? caliper?
or do i still need to use the truck caliper brakes?
can i put a truck spindle on the camaro a-arms w/ truck bj's?

Ok, this has also sparked my interest...
What year camaro clip/subframe/rotor are you currently using? I may have a simple fix for you, but I need more info.
If it's easier for you... Call me at work 605-348-3850 M-F (9-6 MT)

I think I know how you can get a bolt on 5 on 5 bolt pattern rotor to go onto a stock camaro spindle (depending on year spindle used).

[b00sted]

If you have the 85 style front end and use the 91 camaro rotors why do you have to use the camaro calipers?

They seem to be the same size???

[gringoloco]

If you have the '85 LD brakes, you can keep the calipers. Only thing you will need to swap is rotors...

[b00sted]

here is a dumb one for ya.. How can you tell if they are light duty or heavy duty? This clip is under my 53...

[N2TRUX]

Measure the thickness of the rotor. If they are new, they should be 1" or 1.25" for HD.

[heavychevy79]

Originally Posted by 67 cst swb

P.S. yeah, I've worked in auto parts for 22 yrs, 5 yrs of that at NAPA, so, had lots of time to research stuff like this...
If you wanna talk using stock parts to come up with 6 on 5-1/5" disc brakes PM me, I've researched that as well, If I remember SCOTI helped me on that deal... that was awhile back, If SCOTI doesn't remember helping out, I'll take FULL credit for the research.... Just kidding SCOTI.
Bryan

Man let me in on that, I would love to do a six lug conversion!

[b00sted]

I just want to make sure I am correct on this..

My rotors measure 1.25.. I need to get the 91 1" camaro brake rotor for the perfromanc epckg and calipers to make the swap? Or could I just buy the light duty calipers for the 85 truck and use them with the camaro rotors? This way I won't have to worry with a metric brake line?

Thanks for the help with this...

[87 dually burb]

x2 on the the 6 lug swap
for a 90 burb with 1.25 rotors
lookin to run 07-08 tahoe 20"s

[gringoloco]

Originally Posted by b00sted

I just want to make sure I am correct on this..

My rotors measure 1.25.. I need to get the 91 1" camaro brake rotor for the perfromanc epckg and calipers to make the swap? Or could I just buy the light duty calipers for the 85 truck and use them with the camaro rotors? This way I won't have to worry with a metric brake line?

Thanks for the help with this...

You will not be able to do the swap. You need the '81-up LD spindles...

Originally Posted by 87 dually burb

x2 on the the 6 lug swap
for a 90 burb with 1.25 rotors
lookin to run 07-08 tahoe 20"s

Best bet is aftermarket rotors. There is also a conversion floating around here somewhere that uses '88-'98 stuff...

[meansting04]

now if someone could just make a drop spindle for us drum guys it would be great to run nice wheels a good drop and drums

[87 dually burb]

http://67-72chevytrucks.com/vboard/s...d.php?t=322587
found some info here that may help