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Soft brake pedal on my Gladiator Rubicon

CLM

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Hi, I'm starting a new thread on this after unsuccessfully searching for mention of this problem. Basically the brakes on my truck work fine and are pretty similar to other trucks I've owned, including my previous Gladiator. However the brake pedal on my new truck has a distinctly soft or mushy feel that I don't remember being on the 2020 Gladiator I had. The new one is a diesel so it's heavier in the front, both were Rubicons, and it's unrelated to any wheel or tire changes (same on stock wheels/tires). The brake pedal feel is like what one gets with air in the lines, or a leaking caliper, or a bad master cylinder, or worn out rubber brake lines. There's no fluid loss anywhere, so that rules out an actual leak, but I just don't have enough experience with Jeeps to know if this is typical or not typical. Again, there's no lack of actual stopping power, just this soft pedal that doesn't feel good. I used to race cars and the feeling is similar to when we would overheat the brakes and boil the fluid or cook the pads, which of course hasn't happened with my new truck. I'm totally capable of changing parts or bleeding the system, I just don't know where to start. Any helpful advice or insight would be greatly appreciated!
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IslandFalconer

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Mine has a soft feels like it needs to be bled feel to it as well, when I go from my BMW to the Jeep I have to remember to apply more pressure or the truck will roll when I put it in drive.
but I guess it’s normal for these rigs
 

brianinca

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I'd bleed the brakes. I'm kind of ticked it's DOT3 from the factory, I was figuring to replace the OEM fill with synthetic brake fluid anyway.

Edit to add: I say this because I REALLY like the brakes on the JT, you might have just got the new one that the assembly line had a bad day on.
 
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CLM

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I'd bleed the brakes. I'm kind of ticked it's DOT3 from the factory, I was figuring to replace the OEM fill with synthetic brake fluid anyway.

Edit to add: I say this because I REALLY like the brakes on the JT, you might have just got the new one that the assembly line had a bad day on.
Thanks for the reply. Bleeding the brakes is easy and obvious. I don't think "assembly line had a bad day" applies to brakes. I have heard that it's a known complaint specifically on the diesel Gladiator. If there's a problem with that model, I imagine a recall will happen sometime soon. If not, it will end up at the dealer where they will randomly change parts until they can pretend that they fixed it.
 

SloW8

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Do you have a tazer plugged in?
 

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GRDIESEL

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I have the diesel as well and have the same problem. I find it gets worse at times. At one point I found myself pumping the pedal once to firm it up before stopping.
 

Zach32

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I have been noticing this lately as well. The brakes work fine, but I have noticed if sitting at a light for some time the brake will slowly keep going down. Today it went quite a bit further and the ABS light and Brake light were flashing. I slowly left off the brake as to not creep into the vehicle in front of me and the lights went out and pressure came back like nothing happened. Looks like I am going to make a trip to the dealer and see what they say, I'll keep you guys posted. Also I have no visible leaks anywhere.

BTW I have a Diesel Rubicon all stock.
 

Devil Dog

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My guess is low brake booster pressure.
Diesels don't create vacuum like a gas engine, so boost comes from a hydraulic or electric booster.
 
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CLM

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My guess is low brake booster pressure.
Diesels don't create vacuum like a gas engine, so boost comes from a hydraulic or electric booster.
Thanks guys for the posts, not happy to hear others have the same problem, but maybe that will lead to a fix down the road.
DD, question about the engine vacuum and type of booster? It's a turbo diesel so it has positive manifold pressure on open throttle, but on closed throttle, off boost, why doesn't it have negative manifold pressure? Oh, wait, does a diesel engine even have a throttle plate, or is engine speed controlled by the fuel injection pump? Yeah, if there's no throttle body I get it.
 

brianinca

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One of the things I learned from the heavy mechanics at work, Diesels are WOT all the time.

Thanks guys for the posts, not happy to hear others have the same problem, but maybe that will lead to a fix down the road.
DD, question about the engine vacuum and type of booster? It's a turbo diesel so it has positive manifold pressure on open throttle, but on closed throttle, off boost, why doesn't it have negative manifold pressure? Oh, wait, does a diesel engine even have a throttle plate, or is engine speed controlled by the fuel injection pump? Yeah, if there's no throttle body I get it.
 

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azmojave

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Digging up this older post from a search. I’m experiencing all of the above symptoms on my 21 Mojave. (Gas) If I hit the brakes it feels mushy but if I give them a pump they feel nice and hard. (that’s what she said). Tonight I was at a drive thru and I got the pedal to fade all the way to the floor, but in one pump it was fine. It stops fine, but doesn’t feel like it should. I do, however, remember my JK being this way. I figured it would be better on a new vehicle. I guess not. Anyone get info from a dealer or mechanic?
 

jc99

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Same here, mushy pedal feel on my 2021 JT Rubicon diesel on 37s. I've been searching but not finding much about this issue out there..... Will be watching this thread in case someone comes up with something,
 

ZSum73

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2021 willys 2300 miles and brakes feel soft. Have to put my foot in it to get a solid braking feel or pump once then brake to get a good feel. My wife has a new wrangler 2022 and the brakes are touchy which I'd prefer. Going to ask service to check with oil change in a couple weeks.
 

jc99

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Same here, mushy pedal feel on my 2021 JT Rubicon diesel on 37s. I've been searching but not finding much about this issue out there..... Will be watching this thread in case someone comes up with something,
I did a full bleed replaced all the fluid but there was little change, possibly a slight bit more solid but still there is mushiness in the top of the pedal. Mine is a 2021 JTRD with 14000kms on it. I did some high speed heavy braking tests to the point I got the ABS to engage. If I brake hard enough to get the tires to cause the ABS to activate it's almost like the brakes grab more then what I am pushing them to and are very slow to release/return even after my foot is off.

If I was pulling my 4000lbs trailer and had to emergency brake I would be very concerned with the lack of pedal control I have, it feels like I would end up jackknifing the trailer.
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