'95 C1500 5 To 6 Lug Conversion; Options?; Bigger Brakes? Rear Dis

bugman74 · October 10, 2010

Hi Guys,

I'm looking to convert my '95 GMC Sierra C1500 over to a 6-lug pattern so I can fit some of the more popular 6-lug aluminum rims. I just can't seem to find any decent aftermarket 5-lug rims, and really like the look of Z71/Yukon OEM rims. I want to do this conversion the right way, which means no adapters! I have searched the net and cannot find any documentation on this conversion - If I end up pursuing this, I plan to take some pics and put up a page about it. Yes, I know this conversion won't be cheap. The easiest solution is to buy a whole new truck, but this truck has significant sentimental value.

Anyway, I am trying to figure out my best options at this point, but need lots of help:

Front axle option A) Seems like the easiest thing to do here is to drill the rotors for 6 lug and press new studs in. I would prefer to use blank rotors, where can I find some?

Front axle option B) Not sure about this one... I need to do more research, but it seems like I could swap some front axle components to get the 6-lug. I'm not sure what years will fit, and if they all use the same spindle size. Correct me if I am wrong, but I believe the OEM 6-lug brakes are bigger than the 5-lug? If so, this might be a good way to slightly upgrade the brakes while getting the 6-bolt pattern. Ideally it would be as simple as swapping to a 6-lug rotor and matching calipers. I'm guessing I will at least need the rotors, calipers, caliper brackets, etc. The big concern here is that I might need to swap the spindles also. Not sure how this all would effect my ABS either. Can anyone confirm if this is possible?

Rear axle option A) Seems like the only option here is to find 6 lug axle shafts with the correct number of splines that will be a direct replacement for the 5 lug axle shafts. Then I would obviously need new drums to match. I'm not sure if the 6-lug drums are larger, but that could also mean I would need the wider shoes, larger wheel cylinders, etc. Where can I find these axle shafts?

While I'm at it, seems like it would be a good time to just convert the rears over to discs. Not sure if or how I could accomplish this (5 lug drum to 6 lug disc conversion). Any ideas?

Thanks!!

Mike G · October 11, 2010

Do you plan on buying all new components or will you scavage parts from a donor in the salvage yard? I would start on the front and find out if your local parts supplier sells new spindles. If they do, see if you can do a side-by-side compare of the 5 vs. 6 lug spindles. Of course the 6-lug are generally the 4x's, so that adds a different twist as well. In teh rear, there were in fact 2 different brake set-ups offered. The "heavy half" came with bigger drums... You should be able to find axle shafts with 6-lugs, then buy a disk conversion kit with no problem.

Happy shopping... --Mike

AB Chev · October 20, 2010

Eric, there is not much that needs to be done to the front other than change the rotors. You can purchase them at any parts store. You'll need to ask for 1995 c2500 light duty rotors. Again, they must be for a 7200 Lbs GVW light duty (C1500 not K1500)truck because the 8600gvw rotors are 8 lug. They use the same bearings and have the exact same dimensions as the rotors you have now.

Let me know how it goes.

rodram · October 20, 2010

... other issues to consider... this is another GM "believe it or not" story ...

the 2WD 6-lug axles from the C2500 and from the C1500 F44 option are about 2 to 3 inches shorter (ie., narrower) than the 6-lug 4WD axles ..... hmmmmmh!

so these 2WD trucks were equipped with different rims/wheels than the Z-71 rims that you say you want... the alloy rims or even the plain steel rim off of a 6-lug 4WD have the same bolt pattern, but are slightly narrower width (6.5 in.) and have a significantly different offset ..... so that the 4WD rims will not operate properly on a stock truck with 2WD 6-lug axle ... there is not enough clearance with the frame and steering mechanism on the front... but they might be just OK on the back.

.. bottom line is that if you don't put the wider/longer 4WD axles under this truck then your Z71 alloy wheels are not going to fit anyway ...

My recommendation is.... leave your truck as-is ... and if you really want a different looking truck then get a 4WD or Z71

For me... I have the 2WD C2500 6-lug 16 inch set-up.... and I gave up trying to find other rims for mine.