Like when you let up too much clutch, and the car shudders but doesn't buck, I'm getting that more than before. Just starting from a stop; when I'm already moving it doesn't do it. I just give it more gas and ease out on the clutch more to make is smooth, but it worries me that it didn't do this before (during normal/correct operation). What do I need to check out? Tranny, driveshaft?





If you don't know what I mean, here's another example. It also feels like when on a wet road, and the tires break loose from a stop if you stomp the gas, creating that rumble/shudder of the tires bouncing/trying to grip (I guess?).

If it's driveshaft you shouldnt be able to accellerate out of it. It should continue through the gears.

okey dokey.



oh, and the front diff mount is relatively new, a mazdatrix competition unit. Also I've replaced all bushings that came in the energy suspension kit.

my gslse does that but check the fsm bc theres somethign in there about it i think, the probs go from simple braces and stuff all the way up to engine bearings i think.

Sounds to me like you've got broken motor mounts.





-Justin

Hot spots on the flywheel, pp and clutch disc.

broken motor mount, tranny mount perhaps.

That makes sense, I would always hear a slight clunk when getting on the throttle after shifts.

what makes sense, the motor mounts? im asking bc i have the same symptoms

Motor mounts will last forever if you drive like a Grandma. You all DO drive like Grandma, DON'T YOU?

my mounts dont look so good, one is covered in ps fluid and the other is prob covered in oil.

My roomie had identical symptoms in his S-10 Xtreme - turned out to be the driveshaft rear u-joints. He couldn't even do a burnout. Got the driveshaft rebuild and rebalanced and everything was cured (clunks, squeeks, shaking, etc.)



Put your car on a chassis lift and give it some gas, have someone watch the driveshaft. Easy to diagnose..

Is there any way I can tell this by it standing still, like excessive play? I don't have a chassis lift sitting around.

If you've got the balls, jack the rear and put it on jackstands. BLOCK the front wheels, start 'er up and give her a run. I wouldn't recommend high speed on that. I never tried to check his ujoints by hand so I'm not sure what to look for.

put the jack stands under the suspension arms bc if you dont the joints on the halfshafts might get screwed up from the angle of the wheels

uh, NO. I'm not getting under a running car that's held up by jack stands. I'll take a look under there. If I don't notice anything, I can always swap driveshafts with the one from my parts car and see if anything changes. Then move on to tranny and motor mounts.

i dont really think that would be the driveshaft, but if you have a spare one laying around, might as well try it, at least it's free! but that almost sounds like when my last rear diff went out, it lasted for another week before siezeing.. it started all of a sudden after i changed a tire for my mom, i went to take off, heard a clunk and shudder, then it just clunked anytime i shifted and every now and then while i was driveing

did you ever check the fsm?

Smart man. Don't do it. I lost a friend like that a couple of years ago. It was a sad occasion https://www.nopistons.com/forums/pub...O_DIR#>/11.gif https://www.nopistons.com/forums/pub...O_DIR#>/11.gif

That's sad. You don't really have to get UNDER it, you can just look from the side.

Or, drive to midas and ask if they can put it on their frame lift!

I had this hapen on my S10 a few years ago after I lowered it. The pinion angle was changed on the drive shaft so ti would studder whenever starting off from a stop and would go away after I got moving. Can this happen on an rx7 one piece driveshaft?

its most defenatly your u joint i have the same problem and just ordered a new drive shaft cause mazda made them non servicable after 83 on rx-7's you can always lift up the car high enough to get under it and try turning the drive shaft and right after the housing it should give.

also its very unsafe to drive the car if it is the u joint because it can break and bounce around and destroy the tail of the tranny housing and then catch the ground and serve as a pole vault.

i've heard this as well, but i like to tempt fate, so i drove mine for 2 months on a bad u-joint... although i deffinitly would NOT reccomend it, it sucked my gas mileage, robbed my power, and made my ass sore from the vibrations https://www.nopistons.com/forums/pub..._DIR#>/sad.png

Here are some simple checks.



1. Pop the hood, start the engine, rev it. Does the engine seem to rotate to the pass side excessively? If it does, check motor and tranny mounts.



2. While driving at a steady speed, blip the thottle. Do you hear a clunk from the rear? Check the rear diff mount.



3. Jack car up, with jack stands, check the u-joints. If there appears to be any play in them, remove and check further. Bad u-joints can either bind up or be excessively loose. While the car is up, grab a rear tire and rotate forwards and reverse, any clunking can point to u-joints or the irs, (gears, half shafts)



4. If the shudder is only at standing starts and hard high rpm shifts, I stand by my first post. Eliminate all the others first before you have to pull the tranny.