I have been having an issue as of late with my tranny. I notice when accelerating in 3rd gear there is a constant rattling sound. It sounds just like a heat shield rattle (it's not that). It is def in the tranny. 3rd gear is the only one that does it. It shifts fine with no grinds through all the gears. It's just when I accelerate in 3rd gear(hard are just city driving).

Does it sound like a syncro? I think I will try some Pennisol syncro fluid see if that cures the problem. Would that tell me a syncro or not? Being that the clutch is disengaged when this is happening could it be the input shaft bearing? Would it do it all the time or spraticaly?

 

maybe cat converter vibrating on the shift linkage when in that particular gear? do you have aftermarket exhaust?

 

yea.....I put it in 3rd to see if linkage is hitting anything. It(Linkage) is actually closer when in 2nd gear. I will prolly just throw some syncromesh in there until she blows. It is def inside the tranny.

 

i had the same issue. greddy 2.5" from the headers. mine was just the frequency of everything in 3rd at a certain rpm made the exhaust rattle against an old mount.

 

check ur throwout bearing too