Installed Dual diaphram booster: WOW!

[nosigma]

Its been about 9mo's since I did the swap (I am the original poster here) and I can still lock up all four, I did it tonight on the way from DC to Norfolk. I ran semi-metals in California (lots of mountains to descend) but I now run non metallic pads and shoes. Virginia has very few long steep descents that cant be handled by down shifting and just a little brake. If you don't need the fade resistance run softer pads and shoes and you too should be able to lock up all four. The dual diaphragm booster is the the most important but not the only part you have to carefully select for optimum braking performance.

John

 

[XJ_99]

I just need to figure out everything that needs to be removed........

 

[flexjay87]

just got my new booster setup installed (2002 grand cherokee donor) mines a '87, so it was a real pain, everything came out fairly easy, but the support bracket inside the cab, where the studs go through the firewall was misaligned. so, it was difficult to do, by myself. brake lines would have been much easier if the washer bottle wasn't right in the way. so i modified the radius of the lines coming out of the master cyl., and it barely clears. but that's what you get when you try to install parts that were not designed to fit exactly. but the good news is, that it stops like it should, which is much better, i'd say a good 35% or so better, hard to quantify i guess, but much better for sure.

 

[powerbyaj]

Is the ¼ in spacer required in a 91 Non-ABS when using a WJ MC/Booster?

What is the adverse effect if the spacer is used or not used?

 

[cal]

You just have to bend more of the pinch seam out of the way.

We put one in karstic's 92 not very long ago without the spacer.

 

[jeeperjohn]

Is it worth it at all to fit a WJ booster if you already have the dual booster in a 95? Any other vehicles out there that have more assistance than the dual stock booster that will fit with some mods if needed or does space prevent this?

I've heard that a hydroboost from a mid 80's chevy can be put on.

 

[gixer]

I have a 97 and can never get a good pedal. Its always soft. Any ideas on what booster to get??

 

[C85D4x4]

I have a 97 and can never get a good pedal. Its always soft. Any ideas on what booster to get??

try bleeding the system if ur pedal it to soft

 

[gixer]

I have done that. I have even used a brake bleeding machine from a dealer. No matter what I do its soft and no way can I lock them up. I have been over it and so have others. Any ideas on a better booster for the 97??

 

[cal]

I have done that. I have even used a brake bleeding machine from a dealer. No matter what I do its soft and no way can I lock them up. I have been over it and so have others. Any ideas on a better booster for the 97??

There is no reason to upgrade the booster on the 97, its already dual diaphram with a good master.

Your particular booster may be bad, but you don't need to upgrade it.

 

[gixer]

There is no reason to upgrade the booster on the 97, its already dual diaphram with a good master.

Your particular booster may be bad, but you don't need to upgrade it.

Its always been like this. Had the dealer check it when I bought it back in 97 and they said it was fine. Now with a 8,8 in the rear adn 34;s its not good. I need more stoping power. My buddys 98 is the same way. So we are looking for some thing better.

 

[cal]

Its always been like this. Had the dealer check it when I bought it back in 97 and they said it was fine. Now with a 8,8 in the rear adn 34;s its not good. I need more stoping power. My buddys 98 is the same way. So we are looking for some thing better.

You aren't going to find it without building something very very custom and probably not using vacume. Either something is wrong, or you have unrealistic expectations.

 

[gixer]

You aren't going to find it without building something very very custom and probably not using vacume. Either something is wrong, or you have unrealistic expectations.

I dont think wanting to stop is urealistic. You might but I dont.
The brake system has been checked out and I keep being told all the components are fine. Its still a soft pedal and takes to long to stop. Does not like to hold well on steep hills.
So does any one else have usfull information I am don with Cal at this point.

 

[cal]

I dont think wanting to stop is urealistic. You might but I dont.
The brake system has been checked out and I keep being told all the components are fine. Its still a soft pedal and takes to long to stop. Does not like to hold well on steep hills.
So does any one else have usfull information I am don with Cal at this point.

I'm not trying to be a dick, i actually know what I'm talking about here.

With a dual diaphram booster, stock master, stock front brakes you should be able to damn near lock up 35" tires. If you are getting a squishy pedal *SOMETHING IS WRONG*. I don't care what a mechanic somewhere told you.

Go search for all the advice that you want, you already have what people with very large lifts and tires upgrade to.

 

[TRCM]

I dont think wanting to stop is urealistic. You might but I dont.
The brake system has been checked out and I keep being told all the components are fine. Its still a soft pedal and takes to long to stop. Does not like to hold well on steep hills.
So does any one else have usfull information I am don with Cal at this point.

Pretty stupid thing to say, because he is a wealth of info. Gave me tons of help on my swap.

if you are sure the booster is fine,, then look at your knuchkles. Where the pads ride on the mounting arms can and do develop ridges that will allow the pads to bind and not give full contact. I had to file mine down to get rid of the ridges.

Also, make sure the rear brakes are correctly adjusted

 

[mikedashg]

I dont think wanting to stop is urealistic. You might but I dont.
The brake system has been checked out and I keep being told all the components are fine. Its still a soft pedal and takes to long to stop. Does not like to hold well on steep hills.
So does any one else have usfull information I am don with Cal at this point.

Yeah, useful info: listen to Cal, he knows his stuff. On your year with a soft pedal and no stopping power, there's something wrong.

Make sure you got no air in your lines and your booster is good. There are upgrades you can do once you get that figured out.

 

[gixer]

Ok know we are getting some where. Booster is fine. Its stops don’t get me wrong but it should stop better than this. I have had a ton of people check the system out mechanics and non mechanincs. When I am told by lets say 12 people that every thing is working correctly then I am going to have to say it is. The pedal is soft not squishy. Its not a hard pedal when you hit it. Maybe I am expecting to much . But I have driven many cars and trucks that the pedal gets hard when hit. Not this rig. My buddy has been threw the same as me with his 98. Also on page 2 Gojeep has a picture on there, my booster looks like the one on the left not the one on the right. Should it look like the one on the right? If so then that’s not what I have.

 

[cal]

The one on the right in his picture is what you would find on a 95/96 XJ. Yours will look differeht, with a plastic reservoir on top of the master.

 

[djblade311]

Check this post:
http://www.naxja.org/forum/showpost.php?p=243390974&postcount=2

1. Check Vacuum at the booster:
1. Start the engine and let it idle.
2. Turn off the engine.
3. Wait a minute or so then pull the vacuum hose with the checkvalve from the booster. Did you hear a vacuum whoosh? If the MC is good, you should still have vacuum in the booster for a long time after turning off the engine.

2. Do you have rear drums or rear disks? If you have drums, make sure the adjusters are put on correctly and not backwards
3. If the pedal is soft when moving only and if you get vibes when braking, check your rotors. If they have deep rings in them, get them resurfaced or new ones.
4. Also check your unit bearings. Loose unit bearings will prevent the calipers from properly seating the brake pad against the rotor and you will run out of compression room from the caliper.

have you bled your brakes correctly:
1. Start from the right rear, then left rear, then right front, and finally left front.
2. pump the pedal until it gets as hard as it can. Usually about 10 times.
3. release the bleeder valve until NOTHING but fluid comes out.

If the pedal doesn't firm up after this, suspect the master cylinder or a leak somewhere. Some say a bad booster will cause a hard pedal with high braking effort, not a low soft pedal.

 

[djblade311]

oh yea, Cal knows