Better brakes for the LJ

[I Lean]

On of the caliper options I noticed on the GC was a 350mm caliper. Would that work even better? I know we all want to believe that size does not matter but, unfortunately, it does.

Yes it might...but it also might require a larger wheel to clear.
And, I'm not sure there's a standard mounting dimension from axle center. We might find that we need the caliper for the 350mm to work with the 330mm rotor, or vice versa...

 

[gijohn40]

ok I took the JK caliper off and measured the holes from center to center and I come up with 5.75 inches. I measured from the center of the axle shaft out to the end of the rotor and it comes out to 6 inches or 151mm. 22.69mm from the inside of the caliper bracket to the rotor. 73mm from outside of the rotor to the outside of the caliper bracket. what else do you need measured?

 

[I Lean]

Thanks for measuring...the 5.75" centers kills the WK caliper idea.

 

[astjp2]

I have a pair of GC SRT 8 rotors and 1 caliper sitting in my garage, maybe I need to see if it fits...

I can't help but wonder if the 2014 Grand Cherokee 330mm rotors and calipers would just bolt on to a JK and work?

 

[astjp2]

Here is a pic of the 6 piston Brembo caliper and one comparing it to an XJ knuckle Center to center is about 5.55-5.56 and the bolt diameter is .56"

 

[DAA]

Yes, the original source we went to used those calipers and even larger rotors. I thought about it for half a second, but just too expensive. They'd be awesome though.

- DAA

 

[astjp2]

Yes, the original source we went to used those calipers and even larger rotors. I thought about it for half a second, but just too expensive. They'd be awesome though.

- DAA

DAA, Would you mind supplying the link to the actual mercedes rotors you used? There is a 330mm and a 350mm rotors available. I have everything I need to do this except the rotors and I my just get a used set to try it out...I am on a super tight budget, I got the knucke's for $80 and the calipers for $60, I am installing them on a HP 30 that I picked up to stick into my LJ to get me by.

 

[DAA]

Sure, I used Centric 12835099 from Rock Auto, here. I spent $130 for the pair but it looks like they went up a few bucks. But for going cheap, they have some Durago that would only be $80 for a pair.

There is an AWD and a RWD application, I used the front, RWD. They are the 330mm (335, actually, according to Centric). Note, these are for the GC dual piston calipers. The ones the guy used for the Brembo six piston are 14" for a Shelby GT500.

- DAA

 

[astjp2]

I was looking at the Brembo rotors that are 335mm. I still need to come up with a left caliper bracket, then I can actually start rebuilding this 30 I picked up. I hope to find a steal of a deal for an e-locker.

https://www.rockauto.com/info/249/BR_09A73211_Ang__ra_p.jpg

 

[I Lean]

I'd have to look back at the original article to make sure, but I think the Brembo calipers are the only difference between using 13" rotors and 14" rotors. If that's true, then you could use the larger Sport/AWD rotors for the S550, and everything else would stay the same. (machine work on the rotors, and spacers)

 

[astjp2]

I'd have to look back at the original article to make sure, but I think the Brembo calipers are the only difference between using 13" rotors and 14" rotors. If that's true, then you could use the larger Sport/AWD rotors for the S550, and everything else would stay the same. (machine work on the rotors, and spacers)

There is a large and small brembo rotor, the small one is the same as the centric one that Dave posted. Tim

Those Brembo Calipers like the one I posted above came with 15" rotors and require a huge master cylinder. I also need to find that center bolt that didnt come with it when I ordered it, that is one reason why I never pursued using them. I made brackets to install them on my 68 Charger. I wound up going with Crown Vic cop car calipers that matched the explorer rear brakes that are on the Dana I built.

 

[astjp2]

So were your calipers using the 1629 or the 1455 brake pads?

 

[DAA]

So were your calipers using the 1629 or the 1455 brake pads?

And here are the parts and the cost.

Knuckles – '84-'89 XJ $70
Calipers – 2013 Grand Cherokee 6.4L, Centric 14158011/2, $230
Rotors – 2007 Mercedes S550, Centric 12835099, $130
Pads – EBC Yellow Stuff DP41871R, $175
Bracket bolts – 14x1.5x50, $20
Banjo bolts – Mopar 06508914, $15
Copper washers – Mopar 06502114, $15
Speed bleeders – Dorman 12709 10x1.0.35, $15
Total $670

Whichever cross references the EBC I used. Or whichever is more expensive, would probably be a pretty safe bet.

- DAA

 

[astjp2]

Ok, they cross to a d1455, thanks...I just missed what you posted earlier.

 

[glockman]

Thanks for the write up Dave. I've been on the fence about the WJ conversion for the same reason, not wanting to mess with steering that works. This is a great alternative.

 

[astjp2]

So any feedback on these brakes?

 

[DAA]

Just working great. Nothing but good.

- DAA

 

[astjp2]

So do you stop better? What size tires? I am gathering parts now to do this on an HP30 that I picked up to stick in my LJ...

 

[DAA]

... the weight and rolling resistance of 35's...

...

Average distance for four 50 MPH stops with stock configuration, 120 feet.

...

Average distance for four 50 MPH stops with Better Brakes, 94 feet.

- DAA

 

[DAA]

Just remembering something. Few weeks ago, my buddy Tim, who has ridden tens of thousands of miles in the passenger seat of my LJ, riding shotgun. State highway, cruising 70, spaced off and blew past our turn. Hauled her down to turn around and Tim said "ain't never felt the Jeep stop like that before!".

Sums it up pretty well.

- DAA