So here goes, I don't even know how to explain this but I am gonna give it the old college try.

When I start my car, everything sounds fine. No rough idles, no stutters, no throttle lag... etc. When I put the car in gear, It doesn't seem difficult or resisting at all.

But when there is any load bearing on the gear it sounds as if there is a clunking sound, or a grinding sound either right behind the firewall in the front or directly below me. I can hear it whenever there is a severe load change on the drive train. This is when I am accelerating (Ever so softly- to - Full Throttle) And when I take off the gas. It sounds to me as if something is shifting or grinding. This has been happening for something like 3 weeks.

After around 5-8 minutes this goes away, until the car cools off again, and then its a crap shoot if I will hear it on the way home. Nearly every morning though... its noticeable.

Anyone have ANY idea where to start? I am no auto genius, and I could use any leads you all may have.

Armur wrote:So here goes, I don't even know how to explain this but I am gonna give it the old college try.

When I start my car, everything sounds fine. No rough idles, no stutters, no throttle lag... etc. When I put the car in gear, It doesn't seem difficult or resisting at all.

But when there is any load bearing on the gear it sounds as if there is a clunking sound, or a grinding sound either right behind the firewall in the front or directly below me. I can hear it whenever there is a severe load change on the drive train. This is when I am accelerating (Ever so softly- to - Full Throttle) And when I take off the gas. It sounds to me as if something is shifting or grinding. This has been happening for something like 3 weeks.

After around 5-8 minutes this goes away, until the car cools off again, and then its a crap shoot if I will hear it on the way home. Nearly every morning though... its noticeable.

Anyone have ANY idea where to start? I am no auto genius, and I could use any leads you all may have.

I get the same thing, only behind me, on the passenger side. I think yours is likely the rear (dogbone) motor mount. Mine is probably the rear differential front mount. Bushings are cold and stiff, so there's movement at that point, and once they're warmed up and flexible again, the movement is gone, and the noise goes away.

At leas that's my theory....I'll know for sure if my diff falls off.

Take a look at the dogbone engine mount and see how the bushing looks.

My friend had a MS6 with the same symptoms. Ended up being the rear diff as stated above. Kinda of a strange grinding/vibrating noise at certain times when under load.

Would a fluid change help this? If it is anything like the MS3, the stock trans fluid isn't worth crap!

^^wtf are you talking about?!?! This has nothing to do w/ that. If it were tranny fluid of some sort it would either grind putting it into gear/taking it out of gear, he states only when a load is applied, aka engaging the clutch. Its definitely a mount of some sort, now whether its the rmm, diff mounts, or some other mount, thats most likely whats goin on.

When my diff mount went out it sounded the same way mang...its easy to check to, just crawl under the car on the passenger side w/ a flashlight and take a look. It'll be easy to spot as its right behind where the drive shaft connects to the diff. Again, import you be on the passenger side haha.

Maybe its different on the 6 but changing the tranny fluid helped with me with the feel as well as some weird cold noises.

Also, the thrust bearing in general is loud as hell. Regardless if its in gear or not.

I was just throwing a suggestion out there as something else to check.

My '07 Speed6 just started to experience the same issue. Mine is coming from the right front wheel area. I'm traveling for a couple of weeks but once I'm back it's going to the shop. I'll let everyone know what the issue is once I can get it into the shop.

Just had my MS3 looked at at mazda for a clicking noise from front L & R wheel well areas. Turns out to be a TSB for lack of lube on the splines of the half shafts. Easy fix but prob. not the same problem as the clunking. Just throwing it out there.

Yeah, different sound for sure ^^. That would be like a "clinking" vs this which is more or less a lower pitched, harder hitting noise.

I just got my '07 Speed6 back for McDonald Mazda. They really couldn't determine what exactly was causing the noise. They said the only way to really get rid of the noise was to trial and error replace suspension parts. Believe it or not, they did recommend against this and felt that there is no eminent danger with the car and I should just let it warm up.

With that said, I'm gonna let this be my car's quirk. Much better than the oddities in my Lotus.

If anyone does determine the root cause, please let me know. I'm definitely interested in fixing this before summer (when the problem will go away).

Cheers!

Hey thanks for posting your update. I still have the problem, and nothing seems to be "wrong" but its just annoying.

Its a very weird "quirk" indeed and I would love if it would just go away on its own, but thats not likely. I am going to drop off the beast at MazTech up here and see what they say. My guess is that its some mount, of some sort, somewhere. LOL. I'll let you guys know what I find.