Above 6.5k in every gear the engine shakes like a you_know_what. Do you think if I replace the motor and tranny mounts this'll stop? TIA

 

If the motor and trans mounts are bad, youll have a hard time shifting usually
(the trans jumping around will throw off your shifting).

 

hmmm... I don't have a problem shifting it's just when I wind 'er up past 6.5k the drivetrain vibrates pretty hard. Any ideas what it could be?

 

Your pressure plate could have lost some fingers and went off balance.

 

My 85 has the same problem.

I don't have any troubles shifting but I can hear a grinding/rattle sound from the shifter at about the same RPM (6-6.5+).

 

Will the vibe be there in neutral, car not moving?

 

Nope, but after takin' it out for a spin last night I noticed that the vibration/rattle occurs once I enter 3rd gear at around 4k+.

Any ideas?

 

http://www.mazdatrix.com/g2.htm

 

Thanks Carl. I've seen that page a dozen times but never though to look there. I guess I'll hafta try replacing my transmission mounts.

 

sounds like a driveshaft or driveshaft Uni Joints ont he way out!

 

bump'n this ^

I have some more specifics. The engine is smooth as glass from idle to 5800rpm and from 6500 rpm to redline it's REALLY smooth. But between 5800 and 6500 I get a very pronounced vibration out of the driveline. Whadda ya think?

 

Sounds like you are driving into and out of a wobble of some sort - I'd check the rear U-joint. The vibration will travel up through the tranny even if its originates in the rear.

 

Its hitting a harmonic pitch.. things begin breaking at that point.

 

still running the manual fan? one time i had a few loose bolts and that ****** wobbled like a ****!

 

Had the same problem on my 83..12a. I looked everywhere for vibrations.....oddly enough some days the car would run smooth as silk....then HOLD ON..5000 rpm seemed to set it off again when crusing down the pike.
Solution, new drive shaft! Today my 135,000 mile car drives like a new one....one problem though...my fuel mileage has gone to hell....because with out that pesky vibration....I drive the socks off of it now.

 

yea I had exactly the same problem you were describing but it was horrible, i mean horrible it made my mirrors shake like they do when im goin 120+ I was like wtf... put my car on the lift and let it run in 1st off the ground, ****** driveshaft was wobbeling like 1/8 back and fourth near the diff...