NBS rear disc brakes on OBS 10 bolt

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Does it have to be disc? I have an OBS 9.5 14bolt 6 lug with bigger drums (11"? Sorry can't remeber right now) and there was a very noticeable difference in stopping power right away. They almost felt too strong, until I put the 2500/3500 calipers in the front now it feels more balanced.


It's a direct swap, no weird or custom parts needed besides a conversion U joint. And you get a stronger axle out of it and the chance to choose a new gear ratio.
I actually just recently learned about these 6 lug 14 bolts and it's something I'm going to be on the lookout for. I'm definitely going to swap one in. I'll see how those drums work with the 4 piston calipers I just put on from the 2019+ trucks but right now I'm pretty occupied with getting my ls swap finished and driving so eventually it will get done.
 

boy&hisdogs

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I actually just recently learned about these 6 lug 14 bolts and it's something I'm going to be on the lookout for. I'm definitely going to swap one in. I'll see how those drums work with the 4 piston calipers I just put on from the 2019+ trucks but right now I'm pretty occupied with getting my ls swap finished and driving so eventually it will get done.

Look for a six lug 2500 truck. They also came in some 1500s with the F44 package but it's more common to find the 6 lug 2500. Keep in mind that 2wd and 4x4 have different widths so make sure you get the right one. The vast majority of them are 3.73. The 3.42 and 4.10 were an option but I searched for years and never found an actual 6 lug 4.10. I'd go 3.73 unless your are running tiny little lowrider 13" or 14" wheels. Make sure you get one with a G80. You can check the RPO codes on the glove box to see what the truck came with but you should pull the cover to be sure, look for the little springy clicker things inside the spider gears (sorry I don't know the real words for those :anitoof:) That's the G80.

You can't just swap 8 lug to 6 lug by changing the shafts and drums! The actual tube is different and the backing plates are too far back to mount the 6 lug drums. I learned this the hard way and had to buy a whole second axle and brake rebuild kit. And make a note of exactly what year the donor truck was. This came up when I had mine rebuilt by a shop. There's a split somewhere in the 88-98 years for some small parts, I don't remember what but it's not something that affects performance at all.

All my brake mods are:
-NBS 1500 m/c (firms up the pedal a little but that's it)
-Braided stainless lines all around
-3500 SRW front calipers (still uses 1500 pads and rotors, this is what they did on the 454SS)
-Stock 14b SF rear drum brakes (Fully rebuilt with AC Delco parts, including wheel cylinders and new drums)
-Replaced ABS sensors, one of them got covered in grease when I did my balljoints and would engage at low speed (meaning they would suddenly let go when pulling up to a stop sign/light or in a parking lot and I was dangerously close to bumping into other cars o_O )

My truck is lifted on 37s and has a full toolbox, lumber rack and fullsize spare and it still stops better than it did stock.
 

arrg

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Given the complexity of the swap, and the fact that a Trailblazer is a mid-size SUV; why would someone think Trailblazer brakes on the back end of a full-size pickup/SUV are an upgrade?

I'll take the 11.x Duo-Servo drums in proper working condition, thanks very much.
A lot of mid size SUV's from the early 2000's-up (Trailblazer) weigh more than a half ton pickup from the 80's and 90's. My Grand Cherokee is 900 lbs heavier than my truck.
 

boy&hisdogs

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The elusive 14 bolt SF, 6 lug, 4.10 gears does exist! I have it on my truck :biggrin:. Oh, and its G80.

Oh I'm sure they do! But does the owner want to sell? Finding both on the same axle is what's difficult! But if he's running anything near stock sized tires he should be fine with 3.73, which is easy enough to find in the pick and pulls for cheap.
 
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Oh I'm sure they do! But does the owner want to sell? Finding both on the same axle is what's difficult! But if he's running anything near stock sized tires he should be fine with 3.73, which is easy enough to find in the pick and pulls for cheap.
Yea right now I have 3.42 gear with a g80 and have a 265/65/18 tire but I plan on going to a wider and shorter tire and 3.73 gears. From what I see around me the 3.73 is definitely easier to find.
 

Eric Davis

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Pic of parking brake mod, Trailblazer cable " part number is on one of the GM parts boxs above" adapted to existing front cable using metric all thread and metric coupling.
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Hello my 2dr 98 tahoe has the ferrule end leading to the parking brake pedal and I was wondering how did you get the threaded end around the ferrule so you could use the adjustment end connected to the parking cables
 

351FUN

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Given the complexity of the swap, and the fact that a Trailblazer is a mid-size SUV; why would someone think Trailblazer brakes on the back end of a full-size pickup/SUV are an upgrade?

I'll take the 11.x Duo-Servo drums in proper working condition, thanks very much.

He's using 04 Tahoe brakes, and trailblazer parts for the parking brake cable.
 

Caman96

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