WHAT VEHICLE? WHAT BRAKE OPTION CODE?
So the truck pulls to the left when the brakes are applied, we replaced the right caliber as it looked to be the issue and unfortunately it is not.
The master cylinder does has a minor leak, could this be the cause? (I’m debating on upgrading to the newer type eventually)
Probably not. The master cylinder supplies pressure to both front brakes equally. The ABS and/or the combination valve splits the front into left and right sides. It'd be unusual for one side to get air and the other side doesn't.
"Newer type" master cylinder? Please tell me you're not considering converting to the so-called "NBS" master cylinder if you have low-drag front calipers.
what else can cause the pulling issue?
How are the rear brakes? Adjusted properly? Linings and drums in good condition?
Have you EVER bled the (1990 or newer) ABS
using a scan tool to activate the solenoid valves? Does the ABS still have original fluid in it because it's never been properly bled?
Have you looked at the tie rod ends, idler arm, Pitman arm, ball joints, and control arm bushings? Upper control arm bushings have been a known problem on these trucks, and all the other items including lower control arm bushings are a known problem on...everything.
Any good places to get stainless braided lines for obs trucks?
I bought Russell brake hoses, they're not made like OEM with solid metal sections to keep them from rubbing the control arms. I did not know about the better style at that time.
If I were doing that upgrade again, I'd get these:
www.summitracing.com/parts/cst-sbh6055
Free Shipping - Classic Tube StopFlex Brake Hose Kits with qualifying orders of $109. Shop Brake Hoses, Sets at Summit Racing.
www.summitracing.com
I ordered the newer master cylinder this morning
If this is the so-called "NBS" master cylinder,
this is a gigantic mistake if you have low-drag calipers. It's a potential mistake if you screw-up the bore diameter of the new master cylinder vs. the old master cylinder, with non-low-drag calipers. Either way, the "NBS" master cylinder serves no real purpose on these trucks.
All the 1500 trucks have low-drag calipers. (JN, JB or JD, 1, 3, 5, or 6. Examples: JN3, JB5)
The 6-lug 2500 trucks probably have low-drag calipers (JN, JB or JD6) unless ordered with heavy-duty brake option (JN, JB or JD7).
8- or 10-lug trucks don't have low-drag calipers. (JN, JB or JD7, or higher numbers, 8 or JF9)