NBS Front Brake Swap for OBS Trucks

[Helomedic1171]

No. They are 5x4.75. But after a bunch of research I found that there is a bearing assy. from a Dodge Ram that will bolt into the NBS spindle. It has a 5x5.5 bolt pattern. This gives it enough meat to re-drill for our 5x5 pattern. You have to use a custom rotor anyway to get anything bigger than, I believe, 14". So it doesnt change anything price wise.

gotcha. I'm starting with the 6-lug option because I think it will be the easiest to make it work, and a lot of guys will go 6-lug just for more wheel options. I'm trying to figure out a way to be able to use off-the shelf parts so that in the long-term, the brakes won't be cost-prohibitive to run. I'm thinking cut the ears off the GMT-400 spindle like the S-10/F-body guys do, drill/tap for GMT-800 caliper, cut down a 6-lug rotor and turn it into a hub, use a GMT-800 rotor to match the caliper. it's all theoretical and none of it may work, but I'm going to try it. I think there's a significant market out there for 2wd brake upgrades, and if nothing else, it will help out guys that are willing to get greasy and DIY it.

From what I understand:
For OBS 4x4
- upgrading to 00-05 master cylinder only will upgrade brake pedal feel and performance

-upgrading to 00-05 master cylinder AND OBS 1 ton calipers will NOT improve performance but return back to same pedal feel. This is because the new 1 ton calipers offset gains in fluid from NBS master cylinder. This will only improve performance if you have or instal hydroboost, which uses a higher psi to push bigger bores.

-upgrading to NBS master cylinder and NBS knuckles, rotors, calipers, pads is the BEST way to get true improved performance. It requires reaming though.

sounds about right. I have the GMT-800 Master, GMT-800 dual-piston rear brakes, and GMT-400 1/2-ton fronts. definitely a better pedal feel, and much better stopping. still need to get a tapered reamer and the rest of the newer model hardware to do the fronts, but I have one side already. it will probably be a spring project.

ccredell - the purpose of the dodge hub is to re-drill for the chevy pattern, but how do you use the GMT-800 spindle on the 2wd front end? I was thinking machine a little "window" in the spindle, and install the ball joint 180* from stock.... essentially making it like the 4x4 setup. the "window" should give the LCA plenty of room during a turn. not sure how possible that is, but that's my thought. am I nuts?

 

[ccreddell]

am I nuts?

Probably, but in this case thats a positive. In the last couple months, either Truckin' or StreeTrucks did an article putting a GMT800 on the ground. They took off the drop spindles, got some stock ones and reamed the lower ball joint hole so the ball joint would go in from the bottom. Then they flipped the steering B/J so it came up from the bottom also. Thats what made me think these could be adapted to our rigs. Still trying to find a set of NBS spindles to see if this is feasible. If all it takes is making a set of A-arms, this is still workable.

 

[Helomedic1171]

I need to find that article. that sounds really possible. so, ream both B/J holes from the bottom, flip the steering B/J so i comes up from the bottom, and use the stock lower from the bottom, and it might just work - here's a question. would that lower the truck at all? seems like it would give you a nice 1/5-2 inch drop on stock springs.

 

[ccreddell]

Ok, this is still all theoretical, but I've been working on this a while.....

No, you only flip the lower b/j and the t/r. The upper stays where it is. Theoretically it should lower it a couple inches. Now, in the article, they relocated the upper A-arm pivot point up to compensate for flipping the lower b/j, but our OBS A-arms are already spaced for the 'in from the top, up from the bottom' orientation, so we may be just fine.

 

[ccreddell]

Ok, I found the article. StreetTrucks Aug 2013 volume 15 number 8 "Make It Lay" page 92

 

[biggy-p]

cant wait to do this!!!!

ii have a 98 suburban k1500 that i have had for 8 yrs now and sh has been good for but i always felt for as heavy as it was it needed better breaks and im going to do this when i get home from deployment this is a great find!!! has anyone done this and had any long term issues with it at all?

 

[qukon 95]

i did the NBS M/C change what a big improvement i drove 30 mph and pushed down the pedal I got light headed from the stopping force i have
now. I almost got the wrong M/C at the jnk yrd had to find the pic of it on my phone this up grade cost $18.00 with that adaptor.

 

[biggy-p]

18 w/ that adapter? where did you find the adapter that cheap at? this is going to be the first thing i do to my truck when i get home i cant wait to do this on my burban!!!

 

[qukon 95]

MC cost $15.00 at jnk yrd and the adaptor $3.00 at autozone

 

[HighRollerRich]

Did the NBS master cylinder swap. Best thing I've ever done.