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XJ Front Brakes, BIG Brake Options

CobraMarty

NAXJA Forum User
I have read most all of the threads on this site and on others, about this topic of Front 'Big Brakes and have found much information.

Early XJ- 84-89 XJ have the 'old' style knuckle with 2 large mounting lugs for the caliper and brackets to bolt onto, 11" rotors single piston calipers

Later XJ- '90+ XJ with the 'New' style knuckle has the 2 small caliper mounting tabs and the 'wings' for the pads to ride on. 11" rotors single piston calipers. These small caliper mounting lugs are not strong enough to support calipers only. These are the knuckles used and modified by VANCO in their kits.

WJ Knuckles '93-98 12" rotors dual piston calipers 5x4.5 pattern. These can and have been used by many as an upgrade but requires different/modified steering and track bar modification as well as welding on a spacer to the knuckles. Can't just use the lower steering bracket because it will cause significant bumpsteer because it is 3/4"-1" lower than stock XJ. Gets expensive when include the steering and track bar mods.

Australia Co- used Ford calipers and 12" rotors which bolted on to 'early/old' style knuckles. Middle price but expensive with shipping.

Boostwerks- uses 12" rotors and wilwood 4 piston calipers bolted to 'early/old' style knuckles. Expensive, $850-$900, ? if still available.

VANCO- uses 'newer/late' style knuckles that they modify by cutting off the brake pad brackets and caliper brackets and drill and tap the knuckle for 2 additional bolts and uses special adapter brackets. Requires exchange of knuckles. 12" rotors and dual piston calipers, $950-$1050. Have a 13" rotor kit with bigger calipers and more expensive $1500+ and requires 17"+ wheels.

Custom- where special fab and machine skills to use ford, dodge, other spindles, rotors, calipers, different bolt patterns and steering, $$$

Other/Mustang parts- using 'Cobra' calipers dual piston and 13" rotors or using 2014 Mustang GT 13.2" rotors and dual piston calipers. These will require bigger 17"+ wheels. These calipers have the bracket attached and require the strong 'early' XJ knuckles or modify and drill and tap the newer XJ knuckles. To modify the 'newer' knuckles they must be removed and at that point you might as well just replace them with used or new Crown 'early' knuckles.

Any additional options and ideas?
 
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I plan to add BIG front brakes to my '99 'RaceXJ'. I am lucky to have 18" wheels on it already to clear these big rotors and calipers. My other XJs only have 15" wheels.

I plan to use the Crown 'early' style knuckles with the large mounting lugs and my stock steering and Ironman track bar. I am using new Timken late model '99+ hub bearings and new ball joints with 1.75* increased camber lower ball joints.
I got some take-off Mustang parts, 13.2" rotors and dual piston calipers and brackets and stock pads. The rotors are 5x4.5.
Everything is starting to arrive in the mail and will start assembling and mocking up the caliper adapters soon.

Pictures to follow.
 
'90+ 'late' style XJ knuckles with brake pad brackets
52067577.jpg


'84-89 'early' style XJ Knuckles with beefy mounting lugs
mPSMX28Gj91HeoZNHSCq0pw.jpg


WJ '93-98 Knuckles with High steering bracket
26914-md.jpg


VANCO Big Brake Kit
16BBK.jpg


DSC_2369.jpg


Boostwerks Wilwood Kit
fab067.jpg

fab066-1.jpg
 
Thanks, made correction.
 
WJ '99+ Knuckles- more involved, they are 5x5 and need to use XJ hub bearing and weld JKS spacer to knuckle and use WJ lower ball joint and XJ upper ball joint. Have to redrill rotors to 5x4.5, still have the modify the steering and track bar. Gets expensive fast.
 
FYI the Big Brake Kits (vanco) are not being made by vanco anymore.

they are being made by blackmagicbrakes.

and there are 3 sizes, 15", 16", 17" based on your wheel size.

some 15" wheels (like mine) can fit a 16" kit, some cannot. I have yet to hear of anything but a 17" wheel fitting a 17" kit.
 
Ooh add hydroboost to your big brake kit!

But seriously I'm interested in the early knuckles/mustang stuff. Overall cost? And does the mustang stuff bolt right up to those early knuckles?

I was pretty interested in the WJ stuff for the braking/steering benefits, but it does add up fast and my jeep isn't seeing the trail much these days for a few more years while the kids are still very young. My current steering works just fine now, but I Would like better brakes in the street. ESP with the wife driving it more.
 
There is no WJ 93-98 brakes. The ZJ was 93-98, and had the same brakes the XJ had.

You picture a 99+ knuckle in your 93-98 picture.

The WJ, with its draglink arm and larger brakes, was 99-04 only.
 
Also, the mustang 'cobra' brake upgrade bolts up with WJ knuckles, and not early (or late, or crown) XJ knuckles.
 
Not that I think its an upgrade, i personally feel its an unsafe configuration, comprised of steel, fail and aids - but you should mention the Down East Offroad product too.

It uses WJ knuckles, but cuts the dual piston caliper mount off and uses its own bracket to run a single piston Chevy S10 caliper.

20131202_124033_zpsa7e7e7e2.jpg
 
Of everything you listed here, the vanco 'big' brake (13") kit is probably the best option available. Expensive, but totally worth it. It uses Dodge 1500 rotors and calipers.
 
Of everything you listed here, the vanco 'big' brake (13") kit is probably the best option available. Expensive, but totally worth it. It uses Dodge 1500 rotors and calipers.

for clarification, that is the 17" kit if you are purchasing it. the rotors are 13.5"

and yes. having driven a rig with that kit on 37"s, it is the best brakes you can get.

also forgot to mention the 16" kit uses Ford Explorer sport-trac rotors and calipers.
 
Why in the world would you want to use S-10 calipers?

probably to gain the steering benefit of the WJ knuckle without having to clear extra large calipers... not all wheels will do it.
 
probably to gain the steering benefit of the WJ knuckle without having to clear extra large calipers... not all wheels will do it.

They lose the steering benefit of the WJ knuckle too, as they run inverted T on the drag link arms (one US knuckle, one EU knuckle). They don't get full swing, and the ackerman is wrong.. in general the kit is utter trash.
 
They lose the steering benefit of the WJ knuckle too, as they run inverted T on the drag link arms (one US knuckle, one EU knuckle). They don't get full swing, and the ackerman is wrong.. in general the kit is utter trash.


Mega fail.
 
for clarification, that is the 17" kit if you are purchasing it. the rotors are 13.5"

and yes. having driven a rig with that kit on 37"s, it is the best brakes you can get.

also forgot to mention the 16" kit uses Ford Explorer sport-trac rotors and calipers.

I tried the Vanco 16" kit and now run WJ knuckles and brakes. :D
 
Moving from the Vanco kit to WJ brakes, I noticed a slight improvement in brake performance. Could be a pad difference, as both use dual piston calipers and similar sized rotors.
 
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