I'm getting an increasingly severe clunk upon launch, or when I play with the throttle at low speeds. Is there a bushing in the system that commonly fails? It's a bit too wet for me to get under the car right now, maybe tonight...

I figure it could be the tranny mounts, diff mounts, don't think it's the driveshaft (no vibration, no clunking when decelleration).

I can feel and watch the shifter move when this happens.

Um...130K miles, NA, Vert. I can still wind it to 120mph, and no vibrations.

Front differential mount is broken. If you replace it get a competition unit.

This mount? Is it the bushing going bad, or does the mount weld actually break?

I don't see it pictured that but its right next to/ a little bit behind where the driveshaft bolts up to the diff on the drivers side..

Yeah, they ghosted it out in that pic, but it would be where the 3 or 4 bolts holes are right next to the flange. I know what you're talking about. Might have to get a ratchet strap out and wrap that up for the time being until I can fix it...

Competition mount... (from Mazdatrix.com)



http://mazdatrix.com/pictures/h-susp/2diffmntc.jpg

Guess I shoulda searched! https://www.nopistons.com/forums/pub...#>/biggrin.png

Now I know that the front diff mount is crap, it does exactly what my symptoms are, and it's a PITA to fix!



Great https://www.nopistons.com/forums/pub...O_DIR#>/11.gif

I'll weld it, I ain't paying $120 for a new mount...or I'll fab a new one.

Hope you like vibration https://www.nopistons.com/forums/pub...DIR#>/wink.png

I've replaced all the diff mounts and trans mounts with the comps. I even welded the NEW comp. front diff mount with no extra vibs. I had a clunk before I replaced them. I still have a clunk. I don't know what it is. I have gone all through it...can't find it. Even replaced the drive shaft. The only think I can think of is gear lash in the diff. The way I'm going to find the prob now is, to keep slaming it and when it brakes I'll see it. https://www.nopistons.com/forums/pub...IR#>/smile.png

I have all the competition mounts too, I get some vibration at higher speeds, hmmmm, tires are balanced. One time when I got on it going around a corner I also got a clunk, still confuses me.

I say blow it out, what ever it is. When it hits the ground or starts flopping around, then I know what to fix. Wish I could strap a friend under the car and get on it. I had to do that with the engine bay one time to find a boost leak..Damn.



Sorry to thread jack........

Why have you discounted the drive shaft as the culprit? Pending failure of the front U joint will give you a clunk when launching or shifting in lower gears. Clunk at higher gears means the rear joint is failing. I've had two U joint failures in two different 90's. First was clunk and mild vibration and the second was vibration only (felt in both shifter and steering wheel).



If the U joint is really bad you will get up and down movement at the joint when you twist or push the drive shaft. It is not an absolutet test however. It may be worn enuf to vibrate bit not jiggle with only hand pressure stress/pressure.

don't forget to check your camber link bushings when searching for a clunk from the rear. It's the only thing keeping the relationship between the differential and the subframe a (relatively) static one... so if it gets slop in it, you will definitely notice, because it will allow that elastic relationship between the diff and subframe to have some movement.

I'm assuming you mean me.

I've had driveshaft failure in my other vehicle, I know what it feels like when they loosen up or fail. I'm not expereiencing that. Based on other reports, I'm 100% sure it's the diff mount.

I though I had a front diff mount go bad 3 months ago and replaced it. Then I recognized that the bushing that you are talking about was the problem, and had to replace those too.





2 weekends wasted

yep, my car has a new clunk and I thought it was the diff mount but I checked today, and the diff mount looks fine. The clunk happens every time I go to engage the clutch, and you can feel it in the floor. I suspect it's the camber link bushings. It's starting to get too cold outside to **** with this stuff though https://www.nopistons.com/forums/pub..._DIR#>/sad.png

yep, my car has a new clunk and I thought it was the diff mount but I checked today, and the diff mount looks fine. The clunk happens every time I go to engage the clutch, and you can feel it in the floor. I suspect it's the camber link bushings. It's starting to get too cold outside to **** with this stuff though https://www.nopistons.com/forums/pub..._DIR#>/sad.png [/quote]

I've replaced my camber link w/the on car ajustable one, still have the clunk. Talking about it pisses me off.....now I must to know what the hell it is. https://www.nopistons.com/forums/pub...1047683358.gif



any other ideas?.......

hmmmm. I replaced my drive shaft. I checked the old one before I replaced it and the u-joints didn't have any play. But, I replaced it with a diff. one that I got from rx-7 heaven. clunl still there. The only play I can get from the drive shaft(s) is at the yoke, (meets up with the trans) I've been told, that play has to be there for some reason............any clue???

$5 to the 1st person that tells me what it is https://www.nopistons.com/forums/pub...IR#>/smile.png

Why there is a slip yoke on the driveshaft?

Well, when the rear axle articulates, the distance between the diff and the tranny changes.



Oops, sorry, thinking about my truck https://www.nopistons.com/forums/pub...#>/biggrin.png

The engine/tranny assembly can move forward/back slightly under tourque, you need a slip assembly between that moving assembly and the static rear diff, or you'll start damaging the pinion bearings in the diff. You only need a little bit of slip, but it's easier to make a longer slip that also seals the rear of the tranny, rather than put a flange on the tranny and have a slip within the driveshaft.



I'll PM my address :p



EDIT: Oh, and what kind of play do you have at the tranny? Do you mean it can slip in and out (OK) or that there is lateral play in the slip (not OK). If the latter, then you have wear in the tranny rear seal, and that could very well be your clunk.

yep, my car has a new clunk and I thought it was the diff mount but I checked today, and the diff mount looks fine. The clunk happens every time I go to engage the clutch, and you can feel it in the floor. I suspect it's the camber link bushings. It's starting to get too cold outside to **** with this stuff though https://www.nopistons.com/forums/pub..._DIR#>/sad.png [/quote]

I've replaced my camber link w/the on car ajustable one, still have the clunk. Talking about it pisses me off.....now I must to know what the hell it is. https://www.nopistons.com/forums/pub...1047683358.gif



any other ideas?....... [/quote]

though you have replaced the camber link, are you sure there is no slop at the ends of it where the bolts go through? The adjustable replacement probably has solid bushings, are they a tight fight around the bolts at the ends?

I get strange clunk sometime as well. I've replaced everything from Tranny mounts, to rear end mounts and i still get a slight clunk every now and than when i shift "too fast" or while doing to spirited shifting/driving. This clunk has led me to bielieve that it is either my Driveshaft u-joints or some other part of the rear suspension. I am currently saving a couple hundred $$$ to replace every bushing in the rear end. Any recommendations on bushing company's.. poly/rubber replacements. Also I just recieved my tokico HP non adjustable suspension (full set) in the mail. I have not chose springs. my questions : Do they HAVE To be tokico springs to fit on the tokico struts?



-Markus



"Thanks for the help..." CHEERS!

Since apex13b is the only one who has recognized the camber links importance, I think I'm doing a bad job of explaining it, I was bored so I drew a silly illustration.



Maybe someone will find it useful. This is from my memory, which is not very good, so please excuse any gross inaccuracies, I'm not an artist either https://www.nopistons.com/forums/pub...#>/biggrin.png



http://pengaru.com/~swivel/cars/rx-7/sillydiff.png

what happens when kindergarden prodigies to go college and try to explain a college level concept using kindergarden drawing skills

mine is by front diff mount, broke it drag racing...

did u guys also check the engine mounts? i too have a clunk... it ******* drive me nuts...



it got a lot worse after i got major wheel hop at the drag strip.

hey, if I had a tablet I'd be able to draw alot better. I'm a Unix guy so this whole mouse thing is still difficult for me https://www.nopistons.com/forums/pub...#>/biggrin.png

Oh, I sorry, I ment for the 1st person that tells me what's making the clunk. But, I will send you $5 if you really want. I should of been more clear.



I do get up/down & side to side play at the yoke. Maybe that's the prob. I'll replace the seal. (doesn't leak) I have a new one on hand to... I got it for when I put the other drive shaft in, incase the old one started to leak. I'll pop it in and see.



I thought for sure it was the front u-joint before I replaced it w/ a diff shaft cuz, I get most of the clunk in lower gears and from a stop. Going from 3rd to 4th then 5th doesn't make the clunk.

yep, my car has a new clunk and I thought it was the diff mount but I checked today, and the diff mount looks fine. The clunk happens every time I go to engage the clutch, and you can feel it in the floor. I suspect it's the camber link bushings. It's starting to get too cold outside to **** with this stuff though https://www.nopistons.com/forums/pub..._DIR#>/sad.png [/quote]

I've replaced my camber link w/the on car ajustable one, still have the clunk. Talking about it pisses me off.....now I must to know what the hell it is. https://www.nopistons.com/forums/pub...1047683358.gif



any other ideas?....... [/quote]

though you have replaced the camber link, are you sure there is no slop at the ends of it where the bolts go through? The adjustable replacement probably has solid bushings, are they a tight fight around the bolts at the ends? [/quote]

I had to open the mounting points a tad, to get the ends to go in. It's stout.

You can get the whole poly. kit made by prothane for like $68 at nopi.com. As for the other ones that doesn't come in the kit.....Mazdatrix???



No, I don't think you HAVE to use tokico springs with their struts.

I've just put new ones in with the new engine. Maybe it'll fix it. The old ones and more play then the new ones. Also, I'm fabing a torque brace for it.

We'll see soon.....



Oh, sorry for thread jacking...let us know if replacing the front mount does the job

I've had clunks for years too and never figured out what it was. The mounts and bushings look OK but I'm sure if they were all new, it wouldn't clunk as much. Mine actually happens more just going over bumps (not accelerating or anything) and sounds like it is coming from the one shock tower. https://www.nopistons.com/forums/pub...1047683561.gif

That should be a ez one to fix.....

http://www.mazdatrix.com/h6_86-92.htm Look at "stock rear camber links" Could help.

i am not sure if im talking about the same one but i did make a new mount because the rubber on my diff mount was split alrady so my friend helped me to make a custom metal one. man, after putting it, i dont hear the "thud" noise anymore when i shift my gears. but now , YES, it vibrates a little bit , i also noticed that when i shift from 3rd to second, i get this huge vibration, so huge and shaky that it can give a girl some orgasm. but anyway, yes hope you like the vibration.

everybody is quicck to point fingers at the diff mount, but you also have an exhaust hanging back there on rubber bushings that may have broken, which under acceration, or a speed bump will make it sound as if it is coming from the diff.

You should be able to see/feel a drivetrain clunk in the shifter, like I can.

yes, that is definitely one of the symptoms, you feel the clunk in the shifter. does anyone know what is up with that? bearing? , transmission not mounted properly or the driveshaft not tight enough?