2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

Hearing a clunking noise out in the back...

Thread Tools
 
Search this Thread
 
Old Jul 3, 2006 | 01:41 AM
  #1  
Healing's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: May 2005
Posts: 468
Likes: 0
From: Seattle
Hearing a clunking noise out in the back...

I've noticed this noise especially when I make left turns, or have the steering wheel turned slightly to the left.
I've read this might be a broken differential mount? Or perhaps one of the suspension bushings?
How would I go about replacing this if it is? Can I just get parts form the local autoparts store, or mazdatrix or something?
Thanks in advance.

Last edited by Healing; Jul 3, 2006 at 01:45 AM.
Reply
Old Jul 3, 2006 | 02:00 AM
  #2  
13b4me's Avatar
Banned. I got OWNED!!!
 
Joined: Aug 2004
Posts: 8,789
Likes: 2
From: Jacksonville, NC
If you had a broken diff mount, the sound would be related to longitudenal forces on the drivetrain, rather than lateral... It's probably a broken end link or possibly a-arm bushing... I could be wrong, but it's most likely not the diff mount...
Reply
Old Jul 3, 2006 | 02:20 AM
  #3  
KeloidJonesJr.'s Avatar
strictly business
Tenured Member 05 Years
iTrader: (8)
 
Joined: May 2005
Posts: 6,187
Likes: 0
From: chamber of farts
Maybe there's something in the back that's just slides?
Reply
Old Jul 3, 2006 | 02:29 AM
  #4  
13b4me's Avatar
Banned. I got OWNED!!!
 
Joined: Aug 2004
Posts: 8,789
Likes: 2
From: Jacksonville, NC
Haha maybe it's the jack...
Reply
Old Jul 3, 2006 | 06:43 AM
  #5  
TitosToy's Avatar
very sleepy!!
Tenured Member 10 Years
 
Joined: Jan 2005
Posts: 1,052
Likes: 0
From: Tampa, FL
Originally Posted by 13b4me
If you had a broken diff mount, the sound would be related to longitudenal forces on the drivetrain, rather than lateral... It's probably a broken end link or possibly a-arm bushing... I could be wrong, but it's most likely not the diff mount...
if you had a broken dif fmount, you'll be hearing clunking noises everytime you shift (or shift hard). but if it just happens when turning left check your suspension and steering components (axle, tie rod, etc.)
Reply
Old Jul 3, 2006 | 07:11 AM
  #6  
1987_Gxl's Avatar
ALLyourRX7areBELONGtoUS
Tenured Member 05 Years
 
Joined: Apr 2004
Posts: 357
Likes: 0
From: Shoreline,WA
i get creaking from the rear... time for bushings me thinks
Reply
Old Jul 3, 2006 | 08:18 AM
  #7  
toplessFC3Sman's Avatar
Rotary Freak
iTrader: (1)
 
Joined: May 2006
Posts: 2,169
Likes: 5
From: Ann Arbor, MI
Yea, i had clunking noises in back.. part of it was my socket set and antifreeze bottle sliding around, but part of it was really worn out end links. I got a pair from mazdatrix and they mostly fixed that problem... I think i still need bushings tho
Reply
Old Jul 3, 2006 | 11:28 AM
  #8  
13b4me's Avatar
Banned. I got OWNED!!!
 
Joined: Aug 2004
Posts: 8,789
Likes: 2
From: Jacksonville, NC
Originally Posted by TitosToy
if you had a broken dif fmount, you'll be hearing clunking noises everytime you shift (or shift hard).
Shifting = longitudenal forces
Reply
Old Jul 3, 2006 | 12:13 PM
  #9  
ROTARYROCKET7's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member: 20 Years
 
Joined: Jun 2005
Posts: 3,154
Likes: 1
From: Queens, NYC
Originally Posted by 1987_Gxl
i get creaking from the rear... time for bushings me thinks
I have this same issue, when im accelerating my car is fine, its during shifts or deceleration that the car begins to clunk. I avoid this clunk by giving it a lil gas while im clutching in to put it in neutral.

Now if the diff mount brakes totally off lets say what damage can be obtained on the rear. Improper driveshaft to Diff angle and torsional damage perhaps?

Also the creaking when u hit a bump i think can be bushings and work out shocks., i have the same noise. Guess its time to throw on my complete suspension upgrade ihave laying in my bsmt (Kyb , eibachs and Energy Suspesnion)

jason NYC
Reply
Old Jul 3, 2006 | 01:24 PM
  #10  
TitosToy's Avatar
very sleepy!!
Tenured Member 10 Years
 
Joined: Jan 2005
Posts: 1,052
Likes: 0
From: Tampa, FL
Originally Posted by ROTARYROCKET7
Now if the diff mount brakes totally off lets say what damage can be obtained on the rear. Improper driveshaft to Diff angle and torsional damage perhaps?
if the diff mount totally broke and you didnt do anything about it, you can mess up the driveshaft, and/or differential. without the mount, the torque will push up the driveshaft and differential upwards. the clunkingnoise is the the shaf/diff hitting the body. sometimes you might even feel the car lifting a lil. it's not that bad in the short run but if it's broke you have to replace it
Reply
Old Jul 3, 2006 | 03:53 PM
  #11  
ROTARYROCKET7's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member: 20 Years
 
Joined: Jun 2005
Posts: 3,154
Likes: 1
From: Queens, NYC
Originally Posted by TitosToy
if the diff mount totally broke and you didnt do anything about it, you can mess up the driveshaft, and/or differential. without the mount, the torque will push up the driveshaft and differential upwards. the clunkingnoise is the the shaf/diff hitting the body. sometimes you might even feel the car lifting a lil. it's not that bad in the short run but if it's broke you have to replace it

HOly **** are u ******* serious. Hitting the body nah man i aint gonna drive my car till i get that fixed. Holy godamn crap. I thought it was just the diff banging around up there.

Well ima place my order for the diff, whats the COMP DIFF and REG Mazda diff.

The comp looks good cuase its cheap but the Mazda one is stock and since i got a stock car i dont really mind just the price is the issue

Jason NYC
Reply
Old Jul 3, 2006 | 03:58 PM
  #12  
TitosToy's Avatar
very sleepy!!
Tenured Member 10 Years
 
Joined: Jan 2005
Posts: 1,052
Likes: 0
From: Tampa, FL
Originally Posted by ROTARYROCKET7
HOly **** are u ******* serious. Hitting the body nah man i aint gonna drive my car till i get that fixed. Holy godamn crap. I thought it was just the diff banging around up there.

Well ima place my order for the diff, whats the COMP DIFF and REG Mazda diff.

The comp looks good cuase its cheap but the Mazda one is stock and since i got a stock car i dont really mind just the price is the issue

Jason NYC
it aint really that bad. i had mines broke for 2 yrs. before i fixed it and nothing really happened. just dont be dumping the clutch.
Reply
Old Jul 3, 2006 | 04:00 PM
  #13  
bacek's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Jul 2004
Posts: 664
Likes: 1
From: los angeles
stock is just fine remember the original stock one is about 20 years old so it was due to break
Reply
Old Jul 3, 2006 | 04:01 PM
  #14  
13b4me's Avatar
Banned. I got OWNED!!!
 
Joined: Aug 2004
Posts: 8,789
Likes: 2
From: Jacksonville, NC
Umm dude you're gonna pay out the *** for a new one... I'll tell you what lol... Go price one, and then shoot me a PM...
Reply
Old Jul 3, 2006 | 04:06 PM
  #15  
F1blueRx7's Avatar
Couldn't stay away
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (5)
 
Joined: Jul 2002
Posts: 5,093
Likes: 160
From: Defuniak Springs, FL
Originally Posted by Healing
I've noticed this noise especially when I make left turns, or have the steering wheel turned slightly to the left.
I've read this might be a broken differential mount? Or perhaps one of the suspension bushings?
How would I go about replacing this if it is? Can I just get parts form the local autoparts store, or mazdatrix or something?
Thanks in advance.
Originally Posted by Mazdatrix
This (two per car) link goes on the rear control arm, forward, inboard end/pivot. When they go bad, you get an minor, irritating "clunking" from the rear when going over bumps. They seem to wear out most often on convertibles -- must just be the extra weight in the rear?
http://mazdatrix.com/h6_86-92.htm

Check that there. There are lots of things that clunk in the rear, but this is something else to look at other then the diff mount.
Reply
Old Jul 3, 2006 | 04:14 PM
  #16  
Healing's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: May 2005
Posts: 468
Likes: 0
From: Seattle
Hmm...okay. Thanks for all the input guys, I'll take a closer look at this later. But it looks like that I might have an excuse to upgrade to polyurethane bushings now...lol.
Reply
Old Jul 3, 2006 | 08:29 PM
  #17  
ROTARYROCKET7's Avatar
Eats, Sleeps, Dreams Rotary
Tenured Member: 20 Years
 
Joined: Jun 2005
Posts: 3,154
Likes: 1
From: Queens, NYC
So for a stock FC, not planning on any conversion or serious burnouts, just a reliable FC thats stock and good looking.

With spirited driving. Mazda OEM or COmp DIff mounts (comps looko appealing ot me cuase of price)

Jazer NYC

Last edited by ROTARYROCKET7; Jul 3, 2006 at 08:40 PM. Reason: cant spell my own name
Reply
Old Jul 4, 2006 | 12:28 AM
  #18  
F1blueRx7's Avatar
Couldn't stay away
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (5)
 
Joined: Jul 2002
Posts: 5,093
Likes: 160
From: Defuniak Springs, FL
Frankly, I replaced my 17 year old diff mount with a mazda comp one (AKA SR Motorsports drag launch kit which is the same thing mazdatrix sells except 200 dollars MORE) and I noticed a very small Difference when shifting hard and accelerating. Really really disappointed.

I think to get the full effect from the rear end you need to take your diff mount to a shop and have all the rubber removed from the center and have them weld in metal plates until the bitch is SOLID and doesn't move at all. That will make it very nice and crisp. You run the risk of breaking something eventually with enough Horsepower, but I don't see that happening anytime soon for myself.

Also, if you go with a competition differential mount, Install a pinion snubber (do a search for it) and that WILL make a more noticeable difference if you install it and adjust it properly.
Reply
Old Jul 8, 2006 | 02:04 AM
  #19  
Healing's Avatar
Thread Starter
Senior Member
Tenured Member 05 Years
 
Joined: May 2005
Posts: 468
Likes: 0
From: Seattle
Sorry, got kind of an update on my situation.

So I've paid more attention to my car, and when exactly this clunking happens. It happens whenever I turn my wheel in the slighest to the left. However, I also get this clunking inbetween shifts - right as the clutch disengages, even in going in a straight line, I get clunking. As the clutch reengages, the clunking dissapears, that is until I start turning the wheel to the left side again.

Still definately just the suspension bushings?
Reply
Old Jul 8, 2006 | 02:10 AM
  #20  
Apathy's Avatar
dAracIngPhaRmaCist
Tenured Member 10 Years
 
Joined: Mar 2004
Posts: 877
Likes: 0
From: Fort Lauderdale
Its the diff mount...
Reply
Old Jul 8, 2006 | 02:42 AM
  #21  
13b4me's Avatar
Banned. I got OWNED!!!
 
Joined: Aug 2004
Posts: 8,789
Likes: 2
From: Jacksonville, NC
Bet it doesn't clunk in reverse huh?
Reply
Old Jun 7, 2007 | 12:43 AM
  #22  
SJ_chameleon's Avatar
Rotary Powered
Tenured Member 05 Years
 
Joined: Jun 2004
Posts: 285
Likes: 0
From: Denver, CO
Originally Posted by Healing
Sorry, got kind of an update on my situation.

So I've paid more attention to my car, and when exactly this clunking happens. It happens whenever I turn my wheel in the slighest to the left. However, I also get this clunking inbetween shifts - right as the clutch disengages, even in going in a straight line, I get clunking. As the clutch reengages, the clunking dissapears, that is until I start turning the wheel to the left side again.

Still definately just the suspension bushings?
Hate to drag this up from the dead but I have this exact problem and in my searching it seems that a lot of people have the same problem, clunking sound when turning left, right when clutch disengages, etc.
I was just wondering whether anyone has actually figured out what the problem is? Is it a diff mount or suspension bushings or what?
Reply
Old Jun 7, 2007 | 09:25 AM
  #23  
F1blueRx7's Avatar
Couldn't stay away
Tenured Member: 20 Years
Liked
Loved
Community Favorite
iTrader: (5)
 
Joined: Jul 2002
Posts: 5,093
Likes: 160
From: Defuniak Springs, FL
Originally Posted by SJ_chameleon
Hate to drag this up from the dead but I have this exact problem and in my searching it seems that a lot of people have the same problem, clunking sound when turning left, right when clutch disengages, etc.
I was just wondering whether anyone has actually figured out what the problem is? Is it a diff mount or suspension bushings or what?
Consider the mechanics and physical forces acting on the differential when your performing these actions.

The differential torques forward and backwards depending on drivetrain input.

Deceleration and backing up, the front of the differential is forced down and and the back of it wants to come up. So you need to check the front and rear diff bushings and verify that the bolts in the rear are torqued to the correct amount, the top of the bushings are not worn (where the rubber touches the underside of the trunk on top of the differential).

Consider your front subframe bushings, and consider switching them over to some solid mounts.

Under acceleration the pinion is forced up into the underside of the car. The rubber mount that is there to hold the diff mount in place is ... poorly designed/designed with gentle driving in mind. What you want is a front differential mount that holds the pinion from the top or bottom since thats where the acting forces are. The rear of the differential is forced down into the rubber "crown" mounts. Thats why the torque on the rear bolts is important to get right.

Workarounds: Pinion snubber on the front differential mount, solid mounts from MMR in the rear diff and front subframe.

Do not weld the mount unless you are designing some sort of new cradle for the front of the diff with the correct bracing. The welded diff mounts I've seen by people that think they know what their doing put all the stress on the flimsy tab that holds the the diff mount to the subframe. This snaps pretty quickly.

The best option: Cobra rear diff. www.v8rx7forum.com Andrewb70 I think is the one that makes a custom cradle out of your stock subframe. This doesn't break and reduces, if not eliminates, all rear wheel hop.
Reply
Old Jun 7, 2007 | 09:58 AM
  #24  
Boost or Bust's Avatar
Rotorhead in the making.
iTrader: (1)
 
Joined: Sep 2006
Posts: 172
Likes: 0
From: Maryland
I had the same problem with my 88 base after I did the 5 lug conversion. I realized whenever i took a left turn there was a clunking noise. It was even louder when I went in reverse. I couldn't figure out what it was until I lifted up the car from the rear. It was my rear camber link. It was so bad that I could pull the tire in and out just a little bit. Ever since I changed it I never heard it again.

The only pace I was able to find the rear camber link was on the mazdatrixs site. It's fairly easy to change, it only requires you to take off two bolts.
Reply
Old Jun 7, 2007 | 03:37 PM
  #25  
SJ_chameleon's Avatar
Rotary Powered
Tenured Member 05 Years
 
Joined: Jun 2004
Posts: 285
Likes: 0
From: Denver, CO
Well just to let you all know it turned out to just be some loose lug nuts. Thanks for the help though.
Reply



All times are GMT -5. The time now is 05:48 AM.