New owner with rear noises

I did speak with Fox Shocks yesterday and they recommended a set of their shocks but said shocks would not make as much of a difference on gravel roads at slower speeds since there is not much compression to deal with.
 
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Kinda disagree with the above statement from FOX.
It's called a shock ABSORBER as it absorbs bumps
and irregularities on the driving services at all
speeds.
If your shocks are kinda stiff for setup it could cause
a rough ride which in turn can increase road noise.
Did some googling .
Here are 3 links discussing issues with abnormally loud
Power Steering Pump,
Active Noise Cancelation System,
HVAC system
There is also a pedestrian warning system mentioned in one
of the links that makes a high pitched sound .
So maybe your loud interior noise is caused by one of
these or a combination of the three.

https://www.4xeforums.com/threads/power-steering-loud-af.3219/

https://www.jlwranglerforums.com/forum/threads/4xe-active-noise-cancellation.68088/


https://www.4xeforums.com/threads/somewhat-loud-idling-seems-to-be-a-wot-sound.887/

One thing you may want to check is tire pressure . Depending which tire came with your
Jeep . If using an All Terrain dump it down to 30lbs. Wouldn't be surprised if dealer has
pressure maxed out. That can cause a stiff ride while also increasing road noise .
 
Kinda disagree with the above statement from FOX.
It's called a shock ABSORBER as it absorbs bumps
and irregularities on the driving services at all
speeds.
Actually, it's called a shock absorber because people use words incorrectly.
The rim is just the outer part of the wheel.
The sway bar is actually an anti-roll bar.
Handgun ammo is in a magazine, not a clip.
SCUBA divers don't use oxygen tanks. The vast majority are filled with plain old compressed air. Breathing pure oxygen deeper than 20 feet will kill you.
Springs absorb bumps and irregularities. Shocks control the spring action so you don't bounce for a mile after hitting a bump.
 
Yep... same reason "excuse me while I kiss this guy", "there's a bathroom on the right," and "in the garden of Eden" are not the song lyrics people think they are.

So would shocks really help my issue any at all?
 
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Yep... same reason "excuse me while I kiss this guy", "there's a bathroom on the right," and "in the garden of Eden" are not the song lyrics people think they are.
I think that's more misunderstood (or poorly enunciated) than misused, but your point is still valid.
So would shocks really help my issue any at all?
Probably not, but since we don't actually know the cause, it's not really possible to provide a definitive answer. If you ask a shock company, they will tell you to buy their shocks.
 
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The only reasonable (possibly logical) thing I can come up with, being it is happening in all of them (or should I say 2 of 2 that I have driven) and have eliminated most of the common issues, are surface-caused vibrations coming up thru the tires and suspension into the walls/floor of the vehicle causing resonant frequencies (which I measured with an ETA) in the 30-40Hz frequency range. The top is trapping and exaggerating those frequencies, which are rather annoying. A soft top will probably help some, but we like the hard top for now.

Using dampening material should tame some of the vibrations in the walls/floor, but if we can also dampen them thru part of what they are traveling thru, that might also help.

We are swapping the wheels/tires out from 275/55/20 to 285/70/17, which may help some. We are not doing this because of the noise, we are doing it because we like the look of the 17" wheels and a little larger tire. The 20" wheels just don't look right on there to us (simply our opinion).

I guess we just attack it from several angles and see how much each one might help if any.
 
The only reasonable (possibly logical) thing I can come up with, being it is happening in all of them (or should I say 2 of 2 that I have driven) and have eliminated most of the common issues, are surface-caused vibrations coming up thru the tires and suspension into the walls/floor of the vehicle causing resonant frequencies (which I measured with an ETA) in the 30-40Hz frequency range. The top is trapping and exaggerating those frequencies, which are rather annoying. A soft top will probably help some, but we like the hard top for now.

Using dampening material should tame some of the vibrations in the walls/floor, but if we can also dampen them thru part of what they are traveling thru, that might also help.

We are swapping the wheels/tires out from 275/55/20 to 285/70/17, which may help some. We are not doing this because of the noise, we are doing it because we like the look of the 17" wheels and a little larger tire. The 20" wheels just don't look right on there to us (simply our opinion).

I guess we just attack it from several angles and see how much each one might help if any.
Mmmmm 20" Wheels with a 55 low profile tire.
That my friend would have been good Intel to
share on the first post .
That could possibly be much of the problem .
A low profile tire offers very little forgiveness
or flex. If I'm not mistaken usually low profile
tires run higher pressure as well. Which won't help
your situation .
Most of us run a 17" with the odd 18" out there .
Gives plenty of sidewall for flex & airing down .
That extra sidewall wil also help absorb road noise
and bumps .
On the street like you mentioned it's fine . Going off
road not so much .
Def before you do anything else take care of the tires & wheels .
I'm 90 percent certain it will cut down on noises .
Cause I'm guessing the other Jeep you test drove to
compare had the same tires. For a test and comparison
maybe go to dealer and ask to take a 4 Door JLU with 16 or 17"
wheels for a spin .
Had E rated tires , Rubicon Suspension on a Sahara.
Switched the C load tires and made a ton of difference .
Turns out the E loaded tires are not a good match with
the stiffer Rubicon suspension .
But in @Danarch sitituation he is able to run a E loaded
tire with an AEV lift and suspension . As the Bilsteins are
tuned to the springs and offer a more forgiving ride .
So tires , wheel size, suspension can all effect the ride
quality and noise .
Keep us in the loop. As this thread will help,others .
 
The 20" wheels/tires are standard on the Sahara 4xe, assumed everyone knew this.

Those will be the first thing we change... coming up in a few days, we'll know.

We are going with the Michelin 285/70R17, which I believe only come in a C rating.

We are also changing over to Fox shocks at the same time.
 
I was going to bring up the tire issue as I read through the thread. I didn't realize that Sahara had gone all the way to 20" tires at this point. JKs had 18" which is fine if you are running 35" tires, but for 33" and below 17"s are the way to go.

I'm unsure of how the wheel / tire size will adjust actual noise, but it should make it a better ride. Run them at around 30 psi, get yourself the Jscan app and make the jeep your own. It annoys me that Sahara come with 20"s.. .bleh.
 
JScan is a powerful app that allows you to change aspects your jeep such as tire size, how the lights work, and a ton of other things. Not to mention you can look at your engine codes and clear them. It's basically a doorway into the computer mind of your jeep.

The app itself is free, however there is a $30ish license to unlock full functionality which is completely worth it. The interface is a OBD II Bluetooth dongle that you can get via amazon. There are a ton of them out there, but go with the one that the app suggests. All said, you end up spending around $50. It depends on what the dongle is going for at the moment. Many on this forums uses it.
 
The 20" wheels/tires are standard on the Sahara 4xe, assumed everyone knew this.

Those will be the first thing we change... coming up in a few days, we'll know.

We are going with the Michelin 285/70R17, which I believe only come in a C rating.

We are also changing over to Fox shocks at the same time.
The only way anyone would know the specifics of what is standard or an option is if they researched the product .
Can’t speak for everyone here but myself just involved with my JK . Yeah I knew the hybrid excisted but beyond that don’t know much about it.
That’s the same tire size as my BFG K02. With 30 pounds of pressure measures out to 32”.
Whomever mounts your tire will want to put in 35+ pounds of air pressure . Just tell them 30 lbs .

Other than issue your dealing with now. How do you like Jeep hybrid ? When does it operate
off the batteries? Do the batteries charge off the Jeep at all or is it strictly plug in ?
 
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That’s the same tire size as my BFG K02. With 30 pounds of pressure measures out to 32”.
Whomever mounts your tire will want to put in 35+ pounds of air pressure . Just tell them 30 lbs .
Be aware that your tire pressure system will likely turn on the low air pressure light and you'll get the audible alarm every time you start the Jeep if the tires are inflated to 30 or so.
Something else the JScan will allow you to do- override alarms such as tire pressure.
 
Overall we really like the 4xe over the 2-door J we had. It steers a lot better, smoother ride, more comfortable, quieter on smooth roads and gets great gas mileage if you factor in the electric part, which we use up each on each use in most cases. Last fillup we managed 33 mpg.

We get about 25-30 miles on the all electric before it runs out, but running into town, to worship service and bible class and back, we can do all electric. There's very little recharging going on after it drains down, although it does recharge some. We don't use it a lot... mainly as a pleasure vehicle. It's not a daily driver for either of us. We bought it mainly to take on trips, ride the back roads and explore forestry roads and such.
 
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The 20" wheels/tires are standard on the Sahara 4xe, assumed everyone knew this.
Why? This is a JK forum, so, shockingly, most of us are most familiar with JK Wranglers. Not JL.

But 20" wheels is, sadly, another example of how Jeep has been trying very hard to turn the Wrangler from a tough, capable trail rig right from the factory into yet another vanilla SUV.
 
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Be aware that your tire pressure system will likely turn on the low air pressure light and you'll get the audible alarm every time you start the Jeep if the tires are inflated to 30 or so.
Something else the JScan will allow you to do- override alarms such as tire pressure.
Also be aware that, according to the JScan site, you will need some sort of security bypass module for JScan to write anything to the system, including clearing trouble codes.
 
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Why? This is a JK forum, so, shockingly, most of us are most familiar with JK Wranglers. Not JL.

But 20" wheels is, sadly, another example of how Jeep has been trying very hard to turn the Wrangler from a tough, capable trail rig right from the factory into yet another vanilla SUV.
Because I'm human and make a LOT of mistakes. :)
 
Why? This is a JK forum, so, shockingly, most of us are most familiar with JK Wranglers. Not JL.

But 20" wheels is, sadly, another example of how Jeep has been trying very hard to turn the Wrangler from a tough, capable trail rig right from the factory into yet another vanilla SUV.
I would say that is the purpose of the Sahara badge and always has been. There are a number of other things that have happened over time because they legally can't produce something with TJ simplicity anymore. Much of the tech is required now, as it should be.

The fact that the four door jeep vastly outsells the two door backs up what they have been doing.
 
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