c2500 to c3500 front dually conversion

[stutaeng]

Boy, I really hate to see these nice truck all chopped up and lowered and usually try to avoid this sub-forum....but I'll just chime in

Can you take a look at your glovebox for the brake code? I want to say JH6 or something like that was the heavy duty brakes. The C/K 2500 with big block and diesel had the same brakes as the C/K 3500s, which is the hydroboost system. What engine do you have? On the C/K 3500s, the front brakes are the same, regardless of the SRW vs DRW. The only difference is the dually spacers, as I seem to remember converting from C/K 3500 SRW to DRW all you need to swap is rear axle, add fender flares and front spacers...?

Basically, what I'm saying is that "I think" if you have the hydroboost, you can add the spacers to "convert" to a dually. However, looking at Rockauto, there are different pads for SRW and DRW, so perhaps I'm wrong? Still, looking at the brake RPO will be helpful.

Sorry I couldn't help much.

 

[454cid]

On the C/K 3500s, the front brakes are the same, regardless of the SRW vs DRW. The only difference is the dually spacers, as I seem to remember converting from C/K 3500 SRW to DRW all you need to swap is rear axle, add fender flares and front spacers...?

That's not correct. There are two versions of the JB8 Brake RPO.... SRW and DRW. The DRW trucks, and some SRW (ext. cab, but not crew cabs apparently?) and later GMT-600 vans use calipers with larger pistons, thicker pads, and thicker rotors. I swapped to these components on my SRW regular cab long box.

Given the OP has a 3/4 ton, he may have JD7/JB7 brakes, which are very similar, but I think use the narrower shoes on the rear axle and have the drums behind the hubs.

 

[stutaeng]

That's not correct. There are two versions of the JB8 Brake RPO.... SRW and DRW. The DRW trucks, and some SRW (ext. cab, but not crew cabs apparently?) and later GMT-600 vans use calipers with larger pistons, thicker pads, and thicker rotors. I swapped to these components on my SRW regular cab long box.

Given the OP has a 3/4 ton, he may have JD7/JB7 brakes, which are very similar, but I think use the narrower shoes on the rear axle and have the drums behind the hubs.

Ok, thanks for the information.

 

[454cid]

Also the spacers were 4x4 parts..... 2wd dulleys have the "spacers" built into the rotor. I don't know if they use a different spindle/bearings or not. I suspect they're the same. Using the 4x4 spacers on the 2wd is one of the things I' suggested to the OP (it may work), but it may not work as well as the correct rotors for a couple of reasons. The 4wds have a wide front end, so the spacers may not be long enough on a 2wd. If the spindles and bearings are different on the dually, running the spacer may make for a greater load on bearings that won't take it.

 

[jeff9922]

Also the spacers were 4x4 parts..... 2wd dulleys have the "spacers" built into the rotor. I don't know if they use a different spindle/bearings or not. I suspect they're the same. Using the 4x4 spacers on the 2wd is one of the things I' suggested to the OP (it may work), but it may not work as well as the correct rotors for a couple of reasons. The 4wds have a wide front end, so the spacers may not be long enough on a 2wd. If the spindles and bearings are different on the dually, running the spacer may make for a greater load on bearings that won't take it.

Bell tech shows the same spindle for the c2500 and the c3500 so I would assume the factory spindles would be the same

 

[454cid]

Bell tech shows the same spindle for the c2500 and the c3500 so I would assume the factory spindles would be the same

Means nothing.... maybe Belltech makes a heavier duty spindle suitable for 2500 or 3500 DRW. You don't have Belltech spindles. You have OEM spindles. Check one of the dealer parts websites that gives part numbers. Often ebay sellers will have part numbers listed to, although usually to find the parts on ebay, I need to get the number first and search for it.

Check this site.

https://www.wholesalegmpartsonline.com/cars/Chevrolet/car-parts.html

You'll have to dig a little. They tend to mix 1500/2500/3500 stuff in together.

 

[Dahead76]

The spindles on the C2500 and C3500 are the same. I converted my C2500 to a dually but I had the donor truck right next to it while doing the swap. While I was at it I did a 3/4 drop so I just used the lowering spindles. Everything was a direct bolt on.