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Hey y'all,

So a new grinding noise started about 2 or 3 days ago and I'm not exactly sure where it is coming from but it does not sound pretty.

I just installed the mopar lip kit on Thursday and when I had the front bumper fascia off, everything looked fine. I am 99.9% sure I did not leave anything behind (tools, etc.) from the job, hence I don't think that is what is causing my problem.

Here are the facts that I do know:

Lately I've been getting the P0440/41 code. I bought a brand new gas cap and have been making sure it's been tight and still got the code back once. I unplugged the neg. terminal to reset the ECU and so far it hasn't been back yet but I have a feeling it isn't the gas cap...that it may be the sensor or I do, in deed, have a leak somewhere.

Regarding the grinding noise:

I did just install brand new rotors (cross drilled by R1 Concepts) and their brake pads. I believe the pads are semi-metallic & are now squeaking so I just ordered Akebono Ultimate Ceramic pads to replace those with (they came w/ the rotors - they weren't my choice & I will not tolerate squeaking semi-metallic brakes. I hate them.

It appears to make this grinding noise at low speeds, esp. when pulling out from park/complete stop. At idle the engine appears to be making no strange noises and there are no noises when turning the steering wheel side to side (My reasoning for testing this was thinking CV joint? Control arm? Something suspension?) But it appears maybe not?

I've also noticed it seems to grind more if I'm on an incline - but mainly at low speeds like pulling out of my driveway or driving up the small inclined hill to the shopping center - but climbing my HUGE hill to get to my house at 40mph appeared to not grind at all...

I'm really confused as to what this may be. Any ideas/suggestions I'd truly appreciate it before seeking out my mechanic's time. I like to do things myself if I know what needs changed.

I've heard that these transmissions have a history of dying on their owners...I am at 89k miles now - could this be a possible reason? I was planning on doing a full tranny flush at the 100k tune-up...

Thanks y'all!

Ok so after reading a lot of people claiming that their trannys grinded before failing...I figured the first cheap step I'll take, which I know it definitely due, is a tranny flush. Let's see if this helps and go from there...unless someone has another suggestion as to what the grinding may be.

I did check under my car & it did seem like a few drips (of possible tranny fluid) were on the ground. I checked the level while at normal operating temp & it was still at the "HOT" line so I'm thinking it's just probably 90k miles worth of dirty lol (My sister owned the car for 80k miles and she NEVER keeps her cars maintained....so don't blame or point at me!)

I will get the tran flush done tomorrow & will post with updates.

I would likely guess either LCA bushings or tie rod ends or both.

If it happens at low speeds while the suspension is being compressed and decompressed, ie, curbs, lips of driveways etc, they tend to go frequently and cause all sorts of odd noises.

Easiest way to check is to jack up the car and let the suspension hang and inspect the bushings on the lower control arms for tears, rips, cracking etc.

Thanks for the info Chris - I will check them out tomorrow when I have her on the lift doing the tran flush (as I said, I'm 110% that tran fluid is going to be dirty as all hell anyways due to lack of attention lol) Although I did just have the tie rods replaced 2 months ago and I'm pretty sure in 2008 my sister had the control arms replaced (the car sat from Dec 2009 - Jan 2011) so they'd still be newer...but of course, would never hurt to take a peek

Well I changed the tranny fluid - can definitely say that the car is still grinding and that the tranny is shifting smoother than ever (def. worth the $12 anyhow lol)

I was just reading on fixya a woman with a 2003 SXT who's husband believed her grinding on acceleration & at low speeds was her water pump. The person who answered said that the WP bearings could be going out & they make a grinding noise... I am at 89k

The other possibilities I'm thinking about is along the lines of what Chris suggested...CV joint / bearings. What sort of noise and when would it occur if your bearings were indeed shot?

Addendum: I just thought of this! The other day when I had her up on the lift and I was re-tightening the lug nuts (not fully, of course) but my driver front wheel actually would spin all the way around w/o resistance. Now, this is my first 2WD/FWD vehicle in a long time but IIRC that is not normal...could that definitely be a shot bearing (or both of them)?

Just got back from having my car checked out. The guy claimed that all of my lug nuts were loose so they tightened them all down to 100 ft-lbs, however everything suspension wise seemed sound as could be (tie rods, control arms, and even bearings).

He did say, however, that I am in need of a new lower motor mount, my back tires are cupping, my fronts are still winter tires & my rotors are heating up. I told him I just got delivered today my Akebono ceramic pads (so that should take care of the rotors heating which are cross drilled w/ semi-metallic pads right now)

He said the guy took it for another drive tightening my lugs and didn't hear that grinding noise anymore. Well, on the way home, I made another right hand turn at a T, and guess what - grinding like a mother. I have nooo idea what this is?

Did you check and make sure all the brake bolts were in. At work we had a mazda 6 grinding but when we inspected it everything was good, EXCEPT someone left out a bolt to the caliper and the whole caliper was moving around because it came off and was grinding against the rim.

Hmmm I did have trouble fitting the driver side caliber back on with the new pads! I don't think I forgot any bolts but these pads SUCK - I am installing Akebono ceramics tomorrow so I will double check & triple check my work! Thanks aki

Update: Ok, today I took off the wheels & calipers to install my akebono ceramic pads (which I am loving btw...highly recommended!) and my caliper bolts were not loose at all.

After installing the new pads, I checked & double checked everything - ensuring that the pads, calipers, rotors & wheel were all properly aligned & reinstalled.

So unless I replaced the calipers, everything else braking wise is brand new. This would then eliminate braking & suspension (as the garage looked at my control arms, tie rod ends, & bearings yesterday and said all is sound).

What else can it be? What all would make a grinding noise only while turning right & also going straight only after making a right turn for about 20 feet (then the going-straight grinding stops).

I did just remember, though, that when I went to pick up an exhaust off of Ryan, I did hit a big pothole (right front wheel) when entering his business complex...possible knuckle damage? strut damage? But I don't think that pothole affected anything because that was weeks before...the grinding just happened to start a day or two after installing my lip kit w/ the front bumper off...


Could this motor mount in question be the culprit? Maybe if while turning right at low speeds it's causing the motor to move a little and the vibration from the motor on metal sounds like it's grinding?

Have you checked your wheel bearings?

John, Yes - both sides are nice & tight - no wiggle or play and no sounds. Control arms & tie rods are newer also. Rotors & Akebono ceramic pads brand new.


How difficult is it to replace the motor mounts? According to MPx there are only two motor mounts, both on the passenger side? Then I had read there are three "torque struts" - is that correct? The guy at the garage did say that my lower motor mount (I'm taking a guess that this is the longer motor/tranny mount mentioned on MPx's site?) definitely needs replacing...

Actually the 2 on the passenger side are your torque struts both are easy to change, there is a how to for how to align them correctly. Then there the actual "motor mount" which is also on your passenger side, then plastic "plug" in your wheel well covers the bolt for this. Then there is your tranny mount on then drivers side, the cover for the bolt for this is in the wheel well on the drivers side.

^Correct, there are a total of 4 mounts that secure the engine/trans to the frame. The two torque struts deal with the majority of the abuse, and are the ones that fail commonly. A bad mount can definitely cause noise and vibration. I would take care of that before wasting any more time trying to figure this out. Always fix known issues before diagnosing another, even if you think they're unrelated. I would bet that your 'mechanic' is referring to the lower torque strut, as it is the only one that is actually lower than the rest. With that mileage, if it were me, I would replace both torque struts and the trans mount.

Regarding the brakes, even if the semi metallic pads were only on there a few days, they have already began the bed-in process and in turn a wear pattern on the rotor facing. You should have re-machined the rotors prior to switching the pads. The different compound of the new pads will wear against the rotor differently, and more importantly, have different heat principles. This can (and usually will) cause heat damage to the rotor (warping) and possibly reduce braking performance in several other ways. Also, regarding the statement about the brakes "heating up", let it be said that using semi metallic pads on brand new rotors is NOT going to cause heat issues. If they came with the rotors, chances are they are actually matched closely to the OEM relationship (friction-wise) between the two and are ideal for the application. Ceramic pads may be quiet, but at the cost of performance. Also note that drilled rotors (dimpled, slotted, etc) are generally noisier, sometimes so much so that manufacturers include warnings in the documentation that comes with the rotor (i.e. EBC 3GD slotted and dimpled).

GREAT information OB - thank you So, in your suggestion about changing the two torque struts & the one tranny mount...

Would it be these ones?:




(Photos courtesy of ModernPerformance.com)

Is this truly an easy job to do (torque strut replacement)? I've done a lot of things on vehicles but never had to install motor mounts/torque struts where I was required to support the engine with a floor jack. How much would a typical mechanic / the dealership charge for this - I see for the parts alone are like $200?? That's crazy...

Yep those are the torque struts. The trans mount is actually part of the lower battery tray bracket and will probably cost an arm and a leg from the dealer. If it's ok, you don't have to replace it. The torque struts are the key.

How difficult they are to replace really depends on who will be doing the work. I fix cars for a living and I'd rate them around a 4 on a scale from 1-10. I've heard of people having a hell of a time with them too, so like I said it depends. If you have a floor jack, a block of wood, pry bars, maybe a hammer, and a decent set of metric sockets, you're halfway there. There's a How To around here somewhere I think...

ah ha found it - viewtopic.php?t=21482
and another good one - viewtopic.php?t=43837&highlight=torque+strut+alignment

Thank you OB - you're awesome!! I'm sure with my mechanical skills I can knock this out with no problem. I had come across the proper alignment HT by Dante but was looking for one exactly like BallsDeep made - perfect!

I see Advance Auto has them both for $33.99 - not too bad.


Looking at BallsDeep's write up and exactly where that lower torque strut is located...seems to be exactly where my grinding seems to be coming from - hence why I keep coming back to the right hand side wheel well to diagnose. Also the fact that the garage had mentioned my "lower" motor mount really needs replaced...heck, this might just knock out two birds w/ one mount haha

Well, I just ordered the upper & lower torque struts from Advance Auto List price $33.99 each - I got them for $21.49 each after saving $12.50 off of each one (40% off total price). I will pick them up tomorrow and see about putting them on as long as the rain holds off.

Well, I got the upper & lower torque struts done today. Thank you Dante & BallsDeep for your HT's! Man, what a difference in sturdiness. My two 10mm bolts that hold the trim on were stripped so I just said eff it and installed the bottom one with the trim still on - now that was a real PITA let me tell you haha (but it can be done!) Then, I reinstall everything after doing the lower one...get the tire mounted back on, car lowered, lugs tightened...and what did I forget? That friggin' pencil strut! I had to take it all back off and reinstall it - dang bugger!

Now, I'm a little confused as far as this grinding is concerned...As soon as I finished the upper/lower torq. struts, I go & take the car for a ride. It's raining, but not hard yet. I make a couple right turns and it is still grinding, however, not as loud. It even did it on the first couple straight aways from a stop. I go on about a 10 mile ride (mostly highway) and on my way back, after it seems it was enough time to get the under carriage/suspension/braking/etc. all nice & soaked as it started raining a little harder...no grinding! I even went to the infamous right turn that no matter what it grinds...and I could not hear it.

It may be too early to tell...maybe it was the torque strut & now the engine is settling onto it? Maybe it isn't the engine that's doing the grinding & whatever is, when it's wet, no longer grinds...I'm really about to throw my hands up and take it to the dealer! :gasp:

Old Upper:


New Upper:


New & Old Upper:


Old Lower (this one was shot to hell & back haha):

This thread was from a while ago but just to update, the grinding happened to be the rear section of the SRT exhaust I had not tightened down all of the way.

I caught it grinding the one day & tightened it down - never had the grinding again. She now sports the R/T dual chrome exhaust rear section w/ the SRT catback (has 2 resonators which keeps it nice & quiet).

So it was more of a vibrating than a grinding.

Either way, the chicks dig it.

occasional demons wrote:So it was more of a vibrating than a grinding.

Either way, the chicks dig it.

pro...