Problem with a rattle at 4th gear

[jetmechinnc]

Finally got my car up and running after resto started back in November, mainly just structure stuff, nothing done to engine/trans really, now more trouble shooting.  Would like a suggestion to what to look at or for.  I have a bad rattle/vibration in the front of the car.  Not sure if it's the CV joint, drive shafts, transmission, all the above.  Basically in fourth gear say 60 mph, at level road, I get a bad rattle noise/vibration that can shake the doors.  Doesn't seem to do it 1st gear thru 3rd though.  At least not bad.  Plus, the vibration/rattle goes away immediately if you let off the gas peddle while on the highway so I dont' think its an unbalanced wheel.  It also goes away if you are turning sharply to the left or right or loading up the engine like going up a steep high while pressing the gas peddle. 

Second question, when you shift gears, it clunks/jars the car if you don't ease into gear with the clutch.  I've changed out the upper and lower engine brace bushings and it seems that the previous owner has changed the engine mount near the radiator.  Is there another mount to look for that could be broke/worn/missing?  Something from the shifter to the engine?

Thank you

[94touring]

Motor mounts under the clutch housing?

[jetmechinnc]

Motor mounts under the clutch housing?

I didn't know there was another engine mount to check.  I only seem to see the upper engine brace, the lower brace on R/H side and the mount at the radiator side in the books.  I'll have to check to see if there is one there or if its worn out like othere things I replaced.  Can you see the mount from the top of the motor with a mirror, or do you have to crawl under the car?  Is it near the lower brace on the R/H side?

[MtyMous]

It's pretty difficult to see from the top depending on what you have in the way. Most people can't see it because of the starter. It's on the angled portion of the subframe (exactly like the engine mount on the radiator side) and attaches to the clutch bell housing. If you remove the grille (and any fresh air ducts if you have them) you should be able to look straight through and see it.

In this image, it's the black thing on the right of the clutch bell housing. It will be oriented on the bottom .

[jetmechinnc]

It's pretty difficult to see from the top depending on what you have in the way. Most people can't see it because of the starter. It's on the angled portion of the subframe (exactly like the engine mount on the radiator side) and attaches to the clutch bell housing. If you remove the grille (and any fresh air ducts if you have them) you should be able to look straight through and see it.

In this image, it's the black thing on the right of the clutch bell housing. It will be oriented on the bottom .

Thank you very much!!!  I'll have to check this out after work tonight if it's still day light, otherwise I'll really get into it on my day off Tuesday.  Next up will be finding the rubber mounts, if there are any for the shift linkage.  Guess I'll have to pull the mount to see if it's still serviceable.  I replaced the lower aft subframe mounts with rigid ones after I found the rubber disbonded and them actually doing nothing more than weighing down the car.