Confused about brake upgrades for 93 K1500

[AuroraGirl]

How well does that work if they're currently "WAY out of adjustment" (as @Schurkey phrased it)?

Details please, for the benefit of OP.

Someone pissed in your cereal, I am sorry that happened but I wasnt the one to piss in it. I read the reply you replied to as a general opinion about JB5 and that you were replying that in a good condition JB5 which is getting routine maintenance, you would say go and take drums off and get them adjusted.,

From my view, I was thinking why would you do that if you have kept your JB5 in good condition and do what you are supposed to do (Use the brake, stops in reverse)

It was a misunderstanding, and Im sorry that I did so. I will make myself scarce, I apologize for having said anything.

 

[1998_K1500_Sub]

Someone pissed in your cereal, I am sorry that happened but I wasnt the one to piss in it. I read the reply you replied to as a general opinion about JB5 and that you were replying that in a good condition JB5 which is getting routine maintenance, you would say go and take drums off and get them adjusted.,

From my view, I was thinking why would you do that if you have kept your JB5 in good condition and do what you are supposed to do (Use the brake, stops in reverse)

It was a misunderstanding, and Im sorry that I did so. I will make myself scarce, I apologize for having said anything.

@AuroraGirl, nothing bad intended! I value your posts!

What you said was fine and good, as you explained (above). I didn't understand it that way the first time... I was too hurried, my bad.

I'm serious about the instructions though, assuming now that the brakes are "WAY out of adjustment".

Would it be possible to bring them back into adjustment if he:

- apply it once while stopped, and release?
- apply it and roll forward against it, and release?
- apply it and roll backward, and release?
- how does he know if adjustment took place?
- apply the above steps multiple times?

OP would benefit from details, if this details can be provided.

Even if the 10" brakes are already in adjustment, which steps are needed to keep them in adjustment when using the parking brake?

(edit) Some details about the JB5 rear brakes attached, from 1998 FSM. Notice that I don't understand how the adjustment works on the leading-trailing 10" brakes, so I haven't been able to give any direction.

 

[df2x4]

FWIW as someone who is apparently in the minority and uses my parking brake all the time in a JB5 truck... My rear brakes stay adjusted just fine.

Personally I would not think twice about just upgrading pads/shoes/lines and leaving the JB5 system as it is. I'm very happy with the way mine performs.

 

[1998_K1500_Sub]

FWIW as someone who is apparently in the minority and uses my parking brake all the time in a JB5 truck... My rear brakes stay adjusted just fine.

Personally I would not think twice about just upgrading pads/shoes/lines and leaving the JB5 system as it is. I'm very happy with the way mine performs.

My father had a 1995 K1500 w/ JB5 brakes and it actually stopped better than my 1998 Suburban did (prior to my mods). The funny thing is, I'm sure Dad never used the parking brake!

@df2x4 has made a good point. OP, you may want to follow suit.

My Suburban, being a heavier in the back unlike a pickup, and weighing-in @ 3020# front and 3160# rear, never had good brakes IMHO until I monkeyed with it. So I've posted many times about my mods, but they're perhaps mostly applicable to vehicles like mine... similar weight, similar OE combination valve, similar OE vacuum booster.

Summary: Depending on how GM built and provisioned the original vehicle, the benefit of modifications can differ. Owner changes (camper in the back, etc.) can be significant as well.

$0.02

 

[1992prime]

i have a 93 k2500 454, how do i know what brakes I have?

 

[Schurkey]

i have a 93 k2500 454, how do i know what brakes I have?

Open glovebox door, look at Service Parts Identification (SPID) sticker.

Brake option codes tend to be JNx, JBx, or JDx, where x = some number, typically 5, 6, 7, 8. JN1 was manual brakes, JN3 was the very light-duty crap that was gotten rid-of in the early '90s. The higher the number, the bigger/better the brakes. There's a JF9 brake code, but that's a really-heavy-duty system for high GVW GMT400 trucks.

Alternative: Pull the rear drum, measure the diameter. 1500 pickups tended to get the 254mm (10") leading-trailing shoe drums, which means 1, 3, or 5. the 6 brakes involved 11" Duo-Servo drums, 7 and 8 had 13" drums, 2.5" or 3.5" respectively.

My '97 K2500 454 has JD7 brakes--JD = hydroboost, 7 = 13 x 2.5" rear drums. The front rotors and calipers vary also, but the rear drums are the easiest way to identify the brake options. I'd expect your '93 to be similar, but perhaps there's model-year changes such as vacuum booster vs. hydroboost.

 

[1992prime]

thank you! JD7 it is.

 

[Schurkey]

thank you! JD7 it is.

While it's always "possible" to upgrade the brakes...JD7 is pretty adequate as-is, IF (big IF) they're in proper working order.

Specifically, calipers still floating/sliding on the guidepins, caliper pistons still moving freely on the square-cut seal. Rear brakes in adjustment, adequate shoe life, and the rotors and drums not excessively scored or warped. ABS bled with a scan tool, brake fluid flushed so it's nice and virgin-clean. Brake plumbing in decent condition--no rotted rubber hoses or steel tubes. Master cylinder working properly, etc. My own vehicles have had every possible variation of defect; bad rotors, seized caliper mounts, seized or partially-seized caliper pistons, worn linings, warped drums, ABS issues...you name it.

Brake cables are a problem. Both my trucks have needed replacements. Aftermarket park-brake cables are NOT as nice as originals...but whatchagonnado?

Hydroboost power assist has a history of losing pressure in the accumulator, leading to good power assist when the engine runs, and poor power assist when the engine stalls. And of course they can leak PS fluid. Vacuum booster also have occasional issues.

 

[HotWheelsBurban]

While it's always "possible" to upgrade the brakes...JD7 is pretty adequate as-is, IF (big IF) they're in proper working order.

Specifically, calipers still floating/sliding on the guidepins, caliper pistons still moving freely on the square-cut seal. Rear brakes in adjustment, adequate shoe life, and the rotors and drums not excessively scored or warped. ABS bled with a scan tool, brake fluid flushed so it's nice and virgin-clean. Brake plumbing in decent condition--no rotted rubber hoses or steel tubes. Master cylinder working properly, etc. My own vehicles have had every possible variation of defect; bad rotors, seized caliper mounts, seized or partially-seized caliper pistons, worn linings, warped drums, ABS issues...you name it.

Brake cables are a problem. Both my trucks have needed replacements. Aftermarket park-brake cables are NOT as nice as originals...but whatchagonnado?

Hydroboost power assist has a history of losing pressure in the accumulator, leading to good power assist when the engine runs, and poor power assist when the engine stalls. And of course they can leak PS fluid. Vacuum booster also have occasional issues.

The hydro boost units seem to blow the main seals inside the unit; that's what happened to my truck. Fluid all over the place, big puddle under it. You don't think about how much effort is required to turn the wheel w/o power assistance, when the truck is stationary or moving slowly...till you have to do it! Trust me, it's a LOT!

 

[1994rcsbLS]

jesus... new here to all of this... so much information lol
I have a JB5 system, after reading this( thankfully ) im gonna hold off on doing the nbs swap. I just got my ford 9" setup with disk brakes and stainless lines. going to get that in and re visit. question though....
can bypassing my ABS help with pedal?
SORRY TO THREAD JACK, BUT knowing how threads work id rather just add to this extensively knowledgeable thread than create new and get flamed lol