XJ Big Brake Info

Newest XJ/TJ Big Brake Kit
-uses '11-'14 Durango/Grand Cherokee dual piston calipers and 13.25" Mustang Rotors
-requires 17" wheels
-requires 1.00" spacer, no 'adapter' bracket required
-caliper bracket bolts directly to knuckle mounting lugs
-maintains stock steering or any other steering system
-no welding, no relocating sway bar links, no replacing existing steering
-See thread on Cherokee Forum CLICK HERE http://www.cherokeeforum.com/f67/17-diy-big-brake-kit-xj-mj-tj-yj-d30-44-a-222937/

MOST IMPORTANT- FOR BIGGER BRAKES ON AN XJ
* * MUST USE THE EARLY '84-'89 XJ KNUCKLES * *
-THESE WILL BOLT ON TO ANY YEAR XJ
-THESE KNUCKLES HAVE LARGE CALIPER MOUNTING LUGS/TABS vs. '90+ knuckles which have integral brake pad wings
-'90+ knuckles can not be used for bigger brake kits
-'84-'89 Knuckles-
     L- Drivers-    Crown 53000625 or APDTY 110864
     R-Passenger- Crown 53000626 or APDTY 110936
     - lower split ring seat installed depth 0.206" (5.23mm)

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JEEP  TJ/XJ/MJ  BIG  BRAKE  UPGRADE
  INSTALLATION  KIT
12”  Rotors  and  Dual  Piston  Calipers
  for  15” STEEL  WHEELS

$115.00 USD Free Shipping ($130 value, 1 stop shopping)

No Welding, No new steering, No relocation of Sway Bar Link or Track Bar Brackets
No Brake Master Cylinder upgrade needed or Proportioning Valve change required
Easier than WJ conversion and Cheaper than Vanco brakes
12.01” x 1.02” thick Vented Centric Premium Rotors
Huge 48mm Dual Piston Calipers

Installation Kit Includes
-1x 14mm drill bit ½” shank, to drill out the knuckle caliper mounting hole ($15)
-4x caliper mounting bolts 14mm 1.5 45mm 10.9 steel zinc plated ($18 shipped)
-12-24x Spacer Washers 14mm 10.9 steel zinc plated  ($4+above)
            2=0.18” thick -late 99.5+ Unit Bearings
            4=0.36” thick –early pre-’99 Unit Bearing
-4x washers 14mm 10.9 steel zinc plated ($1.50+above)
-2x Dorman 12709 speed bleeders M10-1.0x35mm ($15)
-2x Mopar 06508914AA -banjo bolts M10-1.0 ($20)
-4x Mopar 06502114 -copper washers for banjo bolts and hose ($20)
-1x Harbor Freight 4” angle grinder ($18+$6.95 shipping)
-1x Harbor Freight Safety Glasses ($3 above)

MUST PURCHASE
-EARLY ’84-‘89 Jeep TJ/XJ/MJ Front Knuckles R+L (they have caliper mounting lugs)
-XJ lower Ball Joints- (new/used) with ‘screw in piece’ for knuckle, screw in to 0.206" depth

NEED TO PURCHASE  (best price RockAuto.com- $389 + shipping, incl $120 core fee)
-calipers- Centric 141.58009/10  (‘11-‘16 Durango, ’11-’15 Grand Cherokee 330mm rotor)
-rotors x2- Centric 120.65082  (’01-‘05 Ford Sport Trac)
            **need to grind edge of Unit Bearing so rotor fits on hub and seats completely**
-pads- Centric 30014550 semi-metallic, for above calipers

Brake Pad Break-In Procedure
STEP 1-- 4-5 50mph to 20mph moderate stops with no cool down between stops.
STEP 2-- 4-5 30mph to 0 hard stops without locking up or engaging the ABS
with 5 minutes cool down between each attempt.
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Wheel Bolt Spacing-  
5x4.5"- XJ, Mustang, Ford '02 SportTrac(ST)
5x5.0"- WJ, JK, GC, GC-SRT8

Stock OEM Brakes
XJ- '84-'89 Cherokee Early Knuckles with large caliper mounting lugs, 5.50" spacing, 11" rotors, single piston calipers
        '90-'01 Cherokee Late Knuckles with brake pad 'wings', 11" rotors, single piston calipers
ZJ-- '93-'98 Grand Cherokee same brakes as XJ, rear discs 11" rotors (adaptable to XJ rear)
WJ- '99-'04 Grand Cherokee 12" rotors, dual piston calipers, caliper mounting lugs 5.15" spacing, different lower ball joint than XJ, passenger side knuckle with high mount steering (USA model)
        '99-mid'02 Teves calipers, mid'02-04 Akebono calipers-better design
Jeep GC SRT8- '13-'14 6 piston Brembo front 15" rotor, 4 piston Brembo rear 14" rotor
Jeep GC SRT8- '06-'12 4 piston Brembo front 14" rotor, 4 piston Brembo rear 14" rotor

Caliper Mounting Tab Spacing-
Early XJ + '13-14 SRT8 6piston + '11-14 Jeep GC/Durango = 5.5" **Very Important**
WJ = 5.15"
Mustang = 6.0"
Explorer '01 down and '02 up = 5.675"
JK = 5.75"
'06-'12 GC SRT8 4piston front = 4.25"
'06-'12 GC SRT8 rear = 3.5"

'WJ Swap'- Expensive $$$$
-requires WJ calipers and pads (Akebono Calipers BEST vs. Teves Calipers)
-requires WJ Knuckles R+L
-requires welding JKS Spacers to WJ knuckle (if 2WD- don't need spacers)
-WJ rotor (drilled to 5x4.5") + Late XJ hub  ---or---  Ford SportTrac(ST) rotor + Early XJ hub (edge ground)
-requires WJ lower ball joint instead of the XJ ball joint, AC Delco 45D2292 $64.79
-(Top Ball Joint XJ and WJ are the same)
-requires fabricated tie bar and tie rod ends (possibly offset TREs)
-requires fabricated steering drag link bar
-requires fabricated track bar
-requires fabricated track bar mount on axle
-requires fabricated raised axle sway bar mounts
-may require wheel spacers for Teves caliper and TRE clearance on some 15" wheels
-Rusty's WJ Steering + WJ Brake Upgrade Kit, everything above included, $1,325.00 CLICK HERE

XJ Hub Bearing-Early (Composite rotor)
0.20-0.22" taller, 3.22" (82mm) flange to wheel flange surface, Timken #513084 $66.79
XJ Hub Bearing-Late '99.5 (Cast rotor) 
 shorter flange dimension 3.07" (78mm), taller around axle nut, Longer studs, Timken #HA597449 $67.79

.................EARLY (Composite Rotor) Bearing.........................LATE '99.5+ (Cast Rotor) Bearing


Click the image to open in full size.

Brake Pads-
Jeep GC SRT8 '13-'14 Brembo 6 piston Pads- 2.5"x6.25" = 15.65sq.in. X2= 31.25 sq.in./wheel
..15" Rotor Brake Swept Area- 14.875" - 12.375" = 53.47sq.in. X2 = 106.94 sq.in.
..14" Rotor Brake Swept Area- 13.875" - 11.375" = 53.82sq.in. X2 = 107.64 sq.in.
Jeep GC SRT8 '06-'12 Brembo 4 piston Pads- 2.3"x5.5" = 12.65sq.in. X2= 25.30 sq.in./wheel
..14" Rotor Brake Swept Area- 13.875" - 11.575" = 45.97sq.in. X2 = 91.94 sq.in.
Shelby GT500 '07-'12 Brembo 4 piston Pads- no sample yet
..15" Rotor Brake Swept Area- 14.875" -
..14" Rotor Brake Swept Area- 13.875" -
Mustang GT 2014 Pads- 2.0"x4.3" with 0.6" gap in middle  = 7.5sq.in. X2 = 15.0 sq.in./wheel
..15" Rotor Brake Swept Area- 14.875" - 12.875" = 43.58sq.in. X2 = 87.2 sq.in.
..14" Rotor Brake Swept Area- 13.875" - 11.875" = 40.45sq.in. X2 = 80.9 sq.in.
..13" Rotor Brake Swept Area- 12.875" - 10.875" = 37.30sq.in. X2 = 74.6 sq.in.
WJ Pads- 1.73" x 4.25" with 0.13" gap in middle = 7.128 sq.in. X2 = 14.25 sq.in./wheel
..12" Rotor Brake Swept Area- 11.875" - 10.145" = 29.92 sq.in. X2 = 59.84 sq.in.
XJ Pads- 1.65" X ?.??"
..11" Rotor Brake Swept Area- 10.875" -  9.225"  = 26.05 sq.in. x2 = 52.10 sq.in.

Wheels and Brake Upgrades-
15" wheels- 12" and WJ, Cobra or GT caliper, ?13.2" rotor with Brembo 4 piston caliper
16" wheels- 13.2" Mustang GT rotor and Brembo 4 piston caliper
17" wheels- 13.2" Mustang GT rotor and GT caliper, 14" Shelby GT500 rotor and Brembo 4 piston
18" wheels- 14" Shelby GT500 rotor and GT caliper, 15" Shelby GT500 rotor and Brembo 4 or 6 piston
19" wheels- 15" Shelby GT500 rotor and GT or Brembo caliper

Weights-
Caliper and Pads-- XJ=8.5 lbs, WJ(akebono)=17.2 lbs, Mustang GT 2014=10.8 lbs, GC SRT8 6piston=15.8 lbs, GC SRT8 4piston=14.8 lbs,  GC SRT8 4piston(Rear)=6.6lbs, Shelby GT500 4 piston= ?lbs, GC '13 2 piston 20.0lbs
Rotors-- XJ 11"=14.6lbs, WJ 12"=17.4lbs, SportTrac(ST) 12"=18.4lbs, Mustang GT 13.2"=20.8lbs, Mustang GT500 14"(Centric)=24.6lbs, Mustang Shelby GT500 15"=32.6lbs
Mustang Shelby 14" rear rotors=16.1lbs

Master Cylinders for XJ/TJ-
1" bore, Stock XJ, F-12x1BBL, R-10x1BBL, rod 2.12" Centric #130.67018('98 Cherokee)
1.0625" bore, some '98 ?'99-03 Durangos, hit or miss, *must check*, Centric 130.67024 same fittings
1.125" bore, '03 Durango, Viper, Cardone #132967, Dorman #M630162, same fittings
1.125" bore, '03-'10 Viper, '99-'04 Dakota, '99-'01 Durango, Centric #130.67025 premium, #131.67025 standard ?different reservoir
1.250" bore, Dodge '99-'03 1500, 2500, 3500 pickup, Centric #130.67023, same fittings, pressure rod 1.09"(will need to lenghten rod)

Observations-
-Pad Composition seems to make more braking difference than actual pad size
-Pad Size seems to have more to do with heat rejection ability and fade resistance
-Rotor Diameter and Brake sweep area is related and proportional to braking ability
-Rotor Thickness and Mass/Weight have to do with temps, fade resistance and flexing



Track brake temps 1

Note: Only the front brake hardware was upgraded (calipers/rotors), yet significant performance improvements were also notes in the rear brakes due to the fronts improving so much.

2011 Durango Tests 60-0 Braking  
ONLY 6 piston SRT8 Brembo front calipers + 15" rotors, stock rear 1 piston calipers + solid rotors
stock-      1st-128'  2nd-131'  3rd-138'  4th-147'
Brembo- 1st-120'  2nd-115'  3rd-114'  4th-114' NO FADE, IMPROVED BRAKING

Unsprung Weights = caliper lbs + rotor lbs
XJ calipers + 11" rotors-- 8.5 lbs + 14.6 lbs = 23.1 lbs
WJ calipers + 12" rotors-- 17.2 lbs + 17.4 lbs = 34.6 lbs
WJ calipers + SportTrac(ST) 12" rotors-- 17.2 lbs + 18.4 lbs = 35.6 lbs
Mustang calipers + 13" rotors-- 10.8 lbs + 20.8 lbs = 31.6 lbs (LESS THAN WJ)
Mustang calipers + 14" rotors-- 10.8 lbs + 24.6 lbs = 35.4 lbs (about same as WJ)
'13 GC 2 piston calipers + 13" rotors-- 20.0 lbs + 20.8 lbs = 40.8 lbs
Jeep SRT8 4piston calipers + Mustang GT500 14" rotors-- 14.8 lbs + 24.6 lbs = 39.4 lbs
Jeep SRT8 6piston calipers + Mustang GT500 14" rotors-- 15.8 lbs + 24.6 lbs = 40.4 lbs
Jeep SRT8 6piston calipers + Shelby GT500 15" rotors-- 15.8 lbs + 32.6 lbs = 48.4 lbs

ROTORS
ProStop Parts (Pep Boys)
5115G- XJ early 11" rotor  $28.99
5396G- XJ late 11" rotor  $36.99
5118G- WJ 12" rotor  $31.99
54097G- '03 Ford SportTrac(ST) 12" rotor  $47.99
PR945C- WJ Ceramic pads  $50.99
Centric
Centric 120.65082 Ford SportTrac '01 premium 12" front rotor $42.79 RockAuto
Centric 120.61098 Ford Mustang GT '14 premium 13" front rotor $58.79 RockAuto
Centric 120.61089 Ford Mustang GT500 '14, premium 355mm 14" front rotor 26.2lbs, 1.26"thick $65.89 RockAuto
Centric 120.65054 Ford '95-'01 Explorer 4WD Front rotors 11.375"
Centric 125.61106 '13 Shelby GT500 front 380mm 15" high carbon alloy $119
Centric 125.61105 '13 Shelby GT500 rear 350mm 14" high carbon alloy $68
Centric 120.67053 '02-'10 Ram 1500 336mm 13.25" 5x5.5" ?Vanco 17" kit

Calipers
Centric 142.58013/4 '13-'14 Jeep GC SRT8 6 piston front
Centric 142.58513/4 '13-'14 Jeep GC SRT8 4 piston rear
Centric 142.63073/4 '06-'12 Jeep GC SRT8 4 piston front
Centric 142.61119/20 Ford Mustang GT500 4 piston
Centric 141.65057/8 '03-'05 Ford Sport Trac dual 48mm pistons
Centric 141.65037/8 '95-'01 Ford Explorer dual 46mm pistons
Centric 141.58011/2 '11-'14 Jeep Grand Cherokee/Durango 5.7hemi 48mm pistons 350mm rotor
Centric 141.67045/46 '02-'10 Ram 1500 54mm ? 5 15/16" mounting ?Vanco 17" kit

Vanco Big Brake Kits
The 15" wheel Vanco BBK uses 11 3/8" rotors $1060.
The 16" wheel Vanco BBK uses 12" rotors $1060.
The 17" wheel Vanco BBK uses 13.38" rotors  $1485.

JK Big Brake Options
TeraFlex 4303490 Front 13.3" rotors and brackets for stock JK calipers, drilled for 5x5" and 5x5.5" $300
TeraFlex 4303400 Front 13.3" rotors and dual piston calipers and pads, drilled 5x5" and 5x5.5" $700
Mopar Performance P5160051 Front 13" rotors, dual piston calipers and pads, Bigger brake booster and master cylinder $665
Vanco JKBBK Front 13.25" Centric rotor 54mm dual piston calipers Big bore Master cylinder $1250
     ? seems same as TeraFlex 4303400 + bigger bored MC ($700+$200)
K Sport JK BKJP010-83150 Front 8 piston calipers 13" rotors $1700
Wilwood 140-12440-R Front 14" rotors 1.25" thick, requires 18" rims 4 piston calipers $1600
TeraFlex Big Brake Master Cylinder oversize bore 4303450 for any caliper upgrade kit $200
TeraFlex 4304450 Rear Big Brake 13.5" rotors and bracket, for stock JK calipers, $330-$380


ADAPTER BRACKET TO MOUNT MUSTANG GT CALIPERS TO EARLY XJ KNUCKLE





14" MUSTANG GT500 ROTORS AND MUSTANG GT CALIPERS


FINAL ITERATION OF XJ FRONT BIG BRAKES

Early XJ Knuckle and Late Hub Bearing

Side View

Early XJ Knuckle and 2014 GC SRT8 6 piston Caliper bolt spacing

2013 Shelby GT500 14" Rotor with center ground slightly to clear hub center

Backside View

Backside View with spacers and Grade 10.9 Bolts

FINAL ITERATION OF XJ FRONT BIG BRAKE 14"Mustang Shelby GT500 Rotors and Jeep GC SRT8 6 Piston Calipers 

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