Post Lift/Tire Upgrade Brake Problems

[LL Jeeper]

Ok, I'll try to keep it short. Installed 3.5" Coil lift and 315s. Noticed right away (mushy) brakes. Feels like pedal will go to floor without Antilock coming on. My mechanic bled lines and checked for air. Next was dealership who also bled lines and reset something in the computer. Tire size was adjusted in computer by dealer but at 70 mph still says 65 mph. I've heard all sorts of things. "I need better brakes after the upgrades" but I've also been told that others have no brake problem or changes after similar modifications. Bottom line, "Trigger" is not stopping like he did. Not even close! Couple days ago I slammed on brakes, just didn't stop like my 9000lb van or my 7000 lb pickup does. Does not feel right, or safe.

All thoughts and input welcome!

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[LL Jeeper]

Sorry, realized I posted this in the wrong place and can't figure out how to delete it.

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[JPNinPA]

Of course it will not be the same. Few items.
You lifted the vehicle. First you just raised the center of gravity. Given front brakes usually grab more than rear you will get a whip like momentum push from the high CG. Second the springs are likely soft and at a minimum compress further than stock adding to more whip feel.
You put larger diameter and heavier tires on. This weight adds to the positive momentum the brake has to stop.

So without to a larger diameter rotor and better pad maybe dual piston caliper.

At a minimum i would verify even pad wear all around. Verify no pinched or bent lines. With 3.5 in lift did you extend the flex lines at the wheels?
Maybe leaky master cylinder or vac line???


Did you regear to fix the speedo or just program?



Never look down on anyone unless you are helping them up - Jesse Jackson

 

[JPNinPA]

Sorry, realized I posted this in the wrong place and can't figure out how to delete it.

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Ask the forum moderator (;-) nicely) to move it.


Never look down on anyone unless you are helping them up - Jesse Jackson

 

[Jeepergeo]

Taller overall tire and wheel combinations impact braking....the bigger the difference between pre and post tire and wheel swap the bigger the impact.

You might look into more aggressive pads and see if that alone works before going to the expense of upgraded calipers etc.

I went from factory 28s to 33s and stopping was a problem. I added more aggressive pads with slotted rotors, and braking improved a bunch, getting back towards stock. This is on a TJ with front disc brakes and rear drums. I have not touched the drums.

Read more: https://www.jeepz.com/forum/wrangle...re-change-braking-problems.html#ixzz6v4cveZld

 

[CarsonLevins]

You need to pick good tires as well to match your upgrade. 4WheelOnline has a huge selection of tires and wheels. You may want to check them out.