Rear End Noise -- Update?

[drkknight196]

Has anyone actually definitively diagnosed the rear end banging some of us have been hearing? Mine's getting worse. Dealer can hear it, but can't diagnose. They're digging deeper into TSBs for insight, but most of what they've learned about the MM came from me passing on info I learned from this site!

[TripleTransAm]

Just throwing a data point at you...

I got some sort of thump from the rear of the car when taking a left turn at an intersection at a ... ahem.... more aggressive speed today. The road was bumpy, so the turn itself wasn't smooth but rather choppy. After the turn, I *thought* I heard the bumps transmit more noise into the car via louder thumps at each bump, but eventually I either got used to it or it went away.

Not saying it's related to your problem, but maybe it's something involving that funky linkage ahead of the rear axle. Good luck.

[RF Overlord]

When I had my wife in the passenger seat and my mother-in-law in the trunk...OOPS I MEANT in the back seat last week, I thought I heard a slight thump, but it wasn't readily identifiable. I had just finished the new rear sway bar install, and thought maybe I didn't tighten one of the end links sufficiently. With no one in the back, I can't reproduce the sound, so I guess it isn't the sway bar...otherwise, I've never heard a sound from my rear end.

You may now start the "useless booty" jokes, insults, etc...

[BlueMarauder]

My dealer solved a rear end noise. The dealer originally thought the noise was due to bad shock absorbers. When the shock absorbers were removed, the mechanic noticed an improperly installed bushing. The bushing was fixed. The clunking disappeared.

[TripleTransAm]

Originally posted by BlueMarauder
My dealer solved a rear end noise. The dealer originally thought the noise was due to bad shock absorbers. When the shock absorbers were removed, the mechanic noticed an improperly installed bushing. The bushing was fixed. The clunking disappeared.


What were your symptoms? I'd like to know more about this, in case it ever happens to me (or is currently happening, and I just accepted it as it is).

[TripleTransAm]

Originally posted by RF Overlord
I thought I heard a slight thump, but it wasn't readily identifiable.


Hmmm.... new rear sway bar, Mother in Law in back seat, slight thump....

Could have been your Mother-in-Law's head hitting the side glass as you broke-in your new sway bar!

[drkknight196]

Blue Marauder: Thanks for your post -- that's the first new info I've seen on this problem in awhile and I'll get right on that. The only other rational explanation I've seen here (that hasn't already been checked out) is a body-on-frame issue, but no one's actually run that one to ground. There are others here who have had the exact same problem with the clunking noise when turning and driving over a bumpy place in the road.

[BlueMarauder]

The noise occurred mainly over potholes or speed bumps. A very bumpy road did not automatically cause the clunk. However, the clunk did happen more often over very bumpy roads. The clunk occurred when the car was moving. Neither the speed of the car nor whether the car was turning affected the clunk. The dealer needed four days to diagnose and repair the problem. The mechanic stated that the misalignment of a bushing above the shock absorbers caused a noise in the frame of the car. There was no squeak associated with the rear end noise. So far, the noise has not come back.
As an aside, I originally thought the clunk was due to a loose mini-spare tire. However, the noise did not stop when the tire was tightened.

[drkknight196]

Blue Marauder, et. al: Following your lead, service guys checked rear shocks and said bushings (in upper shock arms) looked like they'd been there for 75,000 miles (!) and had an extreme amount of play side-to-side. Ordered new shocks and will install next week. Please tell me more about these bushings that you said are "above" the shocks so I can have them check those, too. Thanks! If this problem gets solved, it will be the last nagging (difficult to diagnose) issue!! (Edit: Mini-spare? Yikes!!)

[BlueMarauder]

I do not have additional information regarding the bushing above the shocks.The dealer stated that it made the correction to the bushing and replaced the shocks. Unfortunately, the mechanic has not yet furnished the written repair order which lists the parts and labor. I will try to furnish the info when I receive it. Glad to hear that the earlier info may have solved your problem.

[Fourth Horseman]

Interesting about the shock bushings. Did you guys never get a little squeek with the pop too? Sometimes I get just the pop or thunk sound, sometimes it comes with a little squeek.

I'll talk to my dealer about the possibility of the shock bushings and see what they say.

Thanks for the ideas!

[TripleTransAm]

Excellent info!

I'm noticing the hollow-sounding "cluck" sound when going over bumpy roads much more, lately. If it's an issue with the bushing, I'll have it corrected once I go in for the seat squeak issue.

Fourth-horseman, are you listening? :D
(edit: didn't realize you had already posted before I completed my post...)


Actually, if it's the bushing I think it is, I can see how it can squeak in extreme circumstances, if the threaded shock shaft was to rub against bare metal! On my GTA, the rear upper shock shaft protrudes through the floor pan (well, the 'trunk' pan as it dips to the floor pan, right behind the rear seats). The threaded shock shaft is then bolted from inside the car, by lifting the carpet behind the rear seats.

The original shocks were isolated by a set of rubber biscuits both inside the car and underneath the car, with the lower biscuit protruding through the shock shaft hole in the chassis in such a way as to isolate the shaft from the metal of the chassis. The biscuits that came with the replacement shocks were just plain flat biscuits, no isolating "sleeve". So within 50 miles, we had metal-on-metal squeaking... it drove me nuts! Luckily I had the old biscuits and re-installed them (they're still on the car, and things are still quiet).

[Fourth Horseman]

You know it! I'm all over this like a cheap suit. :D

I think I'm going to hold off installing my DR rear sway bar until I get the dealer to look at the shock bushing issue. Don't want to give them any possible excuse to say "Hey... this car isn't stock!"

I'll be dropping by my dealership Monday after work to chat with them about it and hopefully get parts ordered for them to install. I'll follow up here and let you all know if it works for me, too. I'm really hopeful. I had just about resigned myself to live with it.

[drkknight196]

Blue -- spoke to service guys about the "bushing above the shocks" and they drew a blank. Anyone know what bushing Blue may be referring to? Looking forward to getting the info on the parts used to repair your problem. Did they replace your shocks also?

[BlueMarauder]

Drkknight196,

The dealer did replace the rear shocks. Unfortunately, I do not have more info about the bushing until I receive the written repair order. The dealer has promised to mail the repair order.

[drkknight196]

OK thanks. The bushing they may be talking about might be the one in the top of the shock arm. If not, I'm clueless.

[Fourth Horseman]

Took mine back to the dealer again today. Explained what BlueMarauder's dealer did to solve his rear suspension noise. My dealer retightened shock mounts and other suspension components to specified torque, drove it around a bit and declared it fixed. I got it, drove it through one elevated driveway and promptly reproduced the same pop noise.

Argh! :mad2:

Looks like I'm going to have to call the service manager and start getting mean. I'm sick to death of this problem and my dealership's inability to fix it. Yay Ford. :down: :down: :down:

[TripleTransAm]

I'd like to throw out another idea for consideration, regarding this popping noise.

I pulled the back wheels off the car this morning, and had a look at the upper shock mount bushings. Looked okay (I didn't unbolt them, nor did I check the torque). However, I did spot something odd.

There are two rubber bumper stops on the axle, one on each side of the car. If you look at the rub pattern of the rubber stop on the passenger's side frame rail, you'll see it might actually clip some sort of bracket that looks welded on. If you compare this with the rubber stop on the driver's side, you'll see there is no bracket welded to the frame rail... all you see is a nice clean rub pattern from where the rubber stop contacts the frame.

My theory: maybe the passenger's side rubber stop "snaps" as it contacts the bracket along with the frame rail? I could clearly see the polished rub pattern on both the frame AND the edge of the welded bracket. If the rubber stop hits the frame rail at not-quite-90-degrees, I can see the rubber stop 'snapping' as it gets snagged by the sharp edge of the bracket.

Might be a possible explanation if it tends to happen when the passenger's side suspension is compressed, going over an irregular surface.

[Fourth Horseman]

I'll give that a look. Thanks TTA.

[TripleTransAm]

Oh yeah, I also noticed a light scuff mark on the side of the shock absorber body, facing outwards, on the passenger's side. Was this scuff mark a result of contact made between the tire sidewall and the shock body during driving? Or was it just a chance contact made between the two as I wiggled the tire off the hub? Dunno. I didn't see the same scuff on the other side, but again... it could be just a fluke.

Another thing to check out, I guess?

[Fourth Horseman]

I don't think I've had my MM leaning anywhere near hard enough to do that. :) I inspected the shocks pretty closely the other day and didn't see any scuffs. Thanks for all the suggestions, though. My dealer is clearly clueless as to the cause so I need all the help I can get. :)

[engine23ccvfd]

I have started having this problem. About a month ago doing my normal high speed turn into my driveway (rt turn clyde) I heard a pop and dint hear it again until Mon and Tuesday of this week. I wanna check my service manual for the bushing but am not sure what a bushing is. If I find a diagram for the rear suspension what exactly would I be looking for?

Thanks

[FordNut]

I'm starting to notice the same thing on mine. Turn into driveway, right turn, and there's a bump just as you turn off the road. Makes a loud pop sound from the right rear. Sounds like it could be some kind of suspension to frame contact.

[TripleTransAm]

I still suspect it's the bump stop that's snapping as it slides over the weld that protrudes past the frame rail. Those of you with this problem should try filing down that edge of the bracket to at least flush with the frame rail... if I'm correct this should allow the bump stop to slide along the frame rail's surface without catching on the protruding metal. Maybe some lubrication in that area would help, too... like some grease on the frame contact point.

[drkknight196]

I replaced my shocks and bushings (bushings don't come with the shocks!) and I haven't noticed the noise since, although I'm not through testing.

[tomd]

Originally posted by RF Overlord
When I had my wife in the passenger seat and my mother-in-law in the trunk...OOPS I MEANT in the back seat last week, I thought I heard a slight thump, but it wasn't readily identifiable. I had just finished the new rear sway bar install, and thought maybe I didn't tighten one of the end links sufficiently. With no one in the back, I can't reproduce the sound, so I guess it isn't the sway bar...otherwise, I've never heard a sound from my rear end.

You may now start the "useless booty" jokes, insults, etc...

Hey RF

Could you REALLY PUT your Mother-in-Law in the trunk and have her listen for the noise? Those of us who have this problem would appreciate her help. :lol:

[TripleTransAm]

I had the opportunity to attack a parking lot entrance at a slightly higher speed than usual (it's the kind that looks like a driveway entrance with the 'sunken' sidewalk and all), this afternoon. I heard what I think is the hollow pop/clunk that you are all hearing.

Definitely came from the passenger's side rear. Now, did I compress the passenger's side suspension enough for the bump stop to 'pop' across the metal bracket I mentioned, or is it really a function of shocks and/or springs making noise? I was wondering if it could be the sway bar links, as this seems to occur mostly when the car's axle is not parallel with the body's horizontal line....

Regardless, it seems fairly easy to reproduce. One of these days I may get around to trying every suggestion one by one until we nail something down.

[drkknight196]

I had the sway bar links replaced and that wasn't the answer. I believe it's the shock/bushings. When the shock was examined closely, it was clear that the lower arm was sliding back and forth across the bushing and the upper bushings were misaligned and malformed.

[TripleTransAm]

In examing the shocks and bushings, were the misalignments and malformities easily detectable with the shocks mounted on the car? I ask this because I took a long look at the passenger shock and the top bushing, and I'll be darned if I could see anything amiss.

Now, maybe things aren't bolted to the right torque, and with time the bushing takes a beating... I'd like to know what to look for (a photo would have been perfect right about now...). I'd hate to miss such a straightforward solution to this problem...

[drkknight196]

The upper bushing malformities were only visible when removed; however, the lower misalignment was readily apparent to my service guys while the car was on the lift without removing anything.

[RCSignals]

Originally posted by TripleTransAm
I had the opportunity to attack a parking lot entrance at a slightly higher speed than usual (it's the kind that looks like a driveway entrance with the 'sunken' sidewalk and all), this afternoon. I heard what I think is the hollow pop/clunk that you are all hearing.

Definitely came from the passenger's side rear. Now, did I compress the passenger's side suspension enough for the bump stop to 'pop' across the metal bracket I mentioned, or is it really a function of shocks and/or springs making noise? I was wondering if it could be the sway bar links, as this seems to occur mostly when the car's axle is not parallel with the body's horizontal line....

Regardless, it seems fairly easy to reproduce. One of these days I may get around to trying every suggestion one by one until we nail something down.

Well I've had something like that happen twice. Each time driving out of the same lot, turning right. From the same side and area you mention. Sounded almost like someone threw something at the car. The first time I looked and couldn't see anything. I opened the trunk, and the actuating cable had come off the trunk key lock. I put it back on.
The second time, the cable was still in place, but I looked around the right exhaust tip, and it had very small bits of hard dark brown bits in it. Can't figure where that came from. No one gets near my car really, and at home it's parked inside.

[BlueMarauder]

I received the repair order from the dealer who fixed the rear suspension clunking. The dealer replaced the two rear shock absorbers but the noise remained. The next step was to "insulate noise to body bushing over right rear shock." The body bushing was repositioned. (I do not know in what manner the bushing was repositioned). Lube was applied to the rear body bushing.
The noise was silenced. I hope that it does not come back.

[tomd]

Anyone hearing a sound when you first stop your car from the back right side? Mine just started doing this, along with the popping sound that happens when turning right up a hill, I've got 6,500 miles on her.

You’ll have to listen real close to hear it, if you have the radio on, you won't. It only happens the 1st time I brake, (come to a complete stop) if I move and stop again, nothing.


:confused:

[JHD7001]

If the shock bushings are part of the noise you guys are referring to, know that there are bushings with a higher durometer rating available. (Harder to compress & therefore distort)

Since from what I've read, these are Tokico :down: shocks, one could source shock bushings from EnergySuspension.com (please get the -G- bushings, they're graphite impregnated, as opposed to the red, yellow, blue, etc).

There's also shock bushings from prothane, kyb, addco & others.

Man, now if I could only get my contact at Koni to do a set of Sport 'Yellows' for this app that wouldn't be $250 ea (custom).

For those not familiar with the bushings others are speaking of, go to koni-na.com & click on the tab for 'catalog' you'll see the upper & lower shock bushings.

[Petrograde]

Where can I get my hands on a service manual for our MMs? I've looked at Hayne's and Chilton's sites and haven't found anything for 2003.

A parts books with exploded diagrams would be great!

[CRC]

I found the clunk from the rear on my MM. The tailpipe over the rear axle on the pass. side will strike the watts link every once in a while like on rough roads or speed bumps. Can tell by the shiny spot on the tailpipe. Lowered the rear of my car approx 1" by moving the ride height sensor. Did not clunk prior to doing this. Anyone who is experiencing this might check out this possibility.

[RCSignals]

Originally posted by Petrograde
Where can I get my hands on a service manual for our MMs? I've looked at Hayne's and Chilton's sites and haven't found anything for 2003.

A parts books with exploded diagrams would be great!

Manuals are available from Helm.

They occasionally turn up on eBay

There is also a DVD available which contains all the manuala. It is often on eBay as well as available from Helm. Some people have talked their Service departments into giving them the previous versions (they come out monthly I think)

[Petrograde]

Thanks a lot RC! I'll check that site.

[TripleTransAm]

As much as I've blasted the Helm (Ford) manuals for errors and a generally weird layout, you STILL can't beat these factory manuals. The Haynes and Chiltons, when compared to factory manuals, are like McDonalds versus a gourmet steak.

[TripleTransAm]

Originally posted by CRC
I found the clunk from the rear on my MM. The tailpipe over the rear axle on the pass. side will strike the watts link every once in a while like on rough roads or speed bumps.


Wow, excellent lead CRC. I'll have a close look at that!

[RF Overlord]

Originally posted by TripleTransAm
I'll have a close look at that!

Hey /Steve...I knew one day you'd have your head up your tailpipe...!

:lol:

[CRC]

Theres a rear end joke there too...but i got nuthin'

[scareme]

ok guys, brougth my car dowm to the dealer and told them to find the noise, this the third time there for the same thing. they called two days later and said it was the trac bar coming form off the axle. replaced it and the noise remained. i threw out the idea of body bushings so they checked. said everything was tight, so they lubricated them. called today and said that is definitely the problem, i get the car back thursday and will give the final result, hopefully they solved it. will keep ya posted.

[tomd]

thanks scareme, yes please keep us posted.

[drkknight196]

OK, problem resolved! As you might remember, I've had almost the entire rear end replaced, to include the shocks and shock bushings without success. Then I mentioned what BlueMarauder had done with good results, and wahlah!! The simple and final fix is to have the right rear body bushing repositioned and lubed (if necessary). Job takes about 10 minutes!!

[mtnh]

drknight: do you mean the bushing that mounts the body to the frame? Is it all the way back by the bumper? Holy moley!

thanks for posting that.

mike

[drkknight196]

I do not know for sure, as I just dropped off the car. But you can call my dealership (229 242-7930) and ask "Sonny," the service rep. Tell him Mr. Berger gave you his name.

[scareme]

Got my car back today and so far the bodymount bushings seem to have been the problem, haven't heard the noise yet, will keep posted

[TripleTransAm]

Got an update on this myself.

I was at the dealer this morning (for ticking and other reasons), and the technician went through most if not all of the body bushings, and had a close look at shock mounts. He checked tightness on several rear end components, and had to significantly tighten the bolt on the passenger's side of the frame where the "watts linkage" (forgive me if I butcher this, I forgot what it's called) is fixed to the frame. In case I got the name wrong, it's that lever'ed contraption that helps locate the diff in its proper place.

I haven't had a chance to attack the same lot entrances at the same speeds that once generated this popping sound from back there, but I will say this: the car is SIGNIFICANTLY quieter on the roads. I was getting used to the noisy back end on rough roads (umm, that would be ALL the roads here!) but now it just seems so TIGHT and quiet, it's like driving another car.

Funny that I had gotten used to this sort of noisy bump reaction from a stiffly-sprung RWD large car and come to expect it, especially after having installed some stiff KYB gas shocks on the '85 Parisienne with an already stiff suspension to begin with. All of a sudden, I now have this large RWD car with great handling but a very quiet rear axle!!!

So, thus far: creaking from the front solved by tightening MANY front suspension components. And now popping/clunking from rear solved (I think) by tightening linkage bolts. Sounds like my car should have come with all those rubber bands holding it together like y'all have been finding lately....

[drkknight196]

TTA -
Yep, my service techs found most of the underside fasteners in need of serious tightening ............ would not like to believe Ford has such poor QA .................

[GordonB]

Drkknight, Tripletransam and others,
Is it possible to think that these `tightening' problems are 300A related or not? Just a thought. Interested in hearing if any other cars have this problem and whether or not they are 300A or 300B models. We do know that Ford has made running changes. We would also hope that they learned as they built our cars.
Our 300B doesn't seem to have any looseness, but then it only has about 550 miles on it.

Gordon B.

[TripleTransAm]

Mine is a Canadian 300A here, which is pretty much the equivalent of the US 300B.

The more I drive the car, the more I think it's simply fantastic. This last improvement from tightening up the rear linkage really changed my car... I'm amazed how much extra noise was going on back there, that I was not paying attention to.

[WolfeBros]

Interesting news TTA.
Was the rear end linkages tightened under load or with the wheels/axle just hanging ??

[TripleTransAm]

Originally posted by WolfeBros
Was the rear end linkages tightened under load or with the wheels/axle just hanging ??

Under load.

The tech checked pretty much all body bushings and said things were tight. Same with several other items (shocks, shock bushings, etc.). But once he came to the watt's linkage mounts, he found one that required a significant amount of tightening.

It was the mount on the passenger's side. The bracket onto which it bolts is the same bracket that is welded to the frame that will probably show signs of interference with the bump stops. I asked about the possibility of the stop rubbing along the frame and 'snapping' over the protruding edge of the bracket, but the tech seemed to feel that the flexible stop would just "give" quietly instead of snapping hard.

Based on drkknight's feedback, I'm almost inclined to have the dealer go over as many of the bolts/fasteners with a torque wrench just to check for more surprises, when I drop it off for the resolution to the ticking problem. This might just become part of my future pre-delivery criteria, too...

[WolfeBros]

Thanks Steve. I will now be checking mine as well.