robwaz98xj

im upgrading my 98 jeep cherokee from dana 30 / chrysler 8.25 to a dana 60 and a sterling 10.5 rear with disk breaks all around. do i need to upgrade booster? im going to grab the one from the f350 i got the axles from just in case and see if it works if not oh well. are there any aftermarket break boosters?

caged

nope, you've got a nice large dual diaphragm booster on there now.
your booster is good for at least 36 inch tires plus.

robwaz98xj

what about the reservoir and the master cylinder?

ct67_72

that you will need to upgrade. a common one to use is the earlier E350 master.

xjmarc

I'm running the stock master on mine and it stops me just fine.

ct67_72

what size calipers and how far down does your pedal go down.
with 2 piston fronts and big rears it will be low. real low. Usually stops fine, just feels scary.
Even on the 60/14b in my chevy (sas swap) the master needed to be upgraded to get the pedal decent. But it would still lock up 39.5's

xjmarc

Twin piston front single rear and plenty of pedal. Guess I got lucky.

ct67_72

wow I guess you did.
There is tons of info on pirate on it also. I believe there was a whole thread dedicated to it, and which masters you could run.

ktmracer419

dont touch the booster. like said your brakes will be better than stock. just have a low pedal. larger diameter master cylinder that pushes more fluid will alleviate that

PingPong

I am running d44/9" both with 3/4 ton chevy calipers, and I am running a 78 grand marquis M/C. It has a 1.25 bore, and uses the same fitting as my 87 XJ. I did have to make my own lines, as I couldnt get them to go on nicely. You do have to adjust out the booster pushrod 1/8. Nice writeups are over on pirate.


I can now be in double low 1st gear, and my barkes hold. Also can lock up 36's