*In 5th below 60 mph the vibration is so loud I think my car is going to fall apart. *Hopefully this is due to a bolt being sheared off in the transmission support plate, or the backbone, not sure which one is sheared as I did not shear it. *I was not told of it until I was like, “WTF IS THAT NOISE MATT!?” *Then he said, “That has to be the bolt I sheared off in one of the under carriage panels.” *So I hope that is the case. *If not, looks like I will be in 4th until 60mph from now on..
I don't think the bolt is your issue. I've driven without bolts in the backbone with no issues. Welcome to harmonic resonance. This is the same effect we saw with another customers Spec 2+ non-SAC. He choose to have it removed in favor of the stock set up. but I have some questions for you....
Do you have the vibration in 4t at all?
do you have any vibration on decel?
Is the vibration on accel or decel , both or steady state?
Is it RPM based or Speed based?
Does your car have the torque arm (structure that connect the rear of the tranny to the front of the diff)?
The vibration is much quiter in 4th than 5th but I still feel it.
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It only occurs on acceleration
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I have not checked rpm, but anything under 60 in 5th gear gets it.* The lower, the louder.
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I am assuming it is rpm based as it does it in 4th gear also, just not as loud.
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And yes my car has the torque arm.* That thing is a huge heavy piece of metal that was in the way constantly.
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And I just found out, its not in the back bone.* It’s the front driver bolt in the transmission support plate.*
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Hope the helps diagnose the problem!
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Thanks randy
I'll check the Manual when I get back into the shop later today. There is a measurement that sets the angle of the drive shaft. You have to use a jack to raise/lower the transmission to a certain position before you torque the bolts on the Transmission end of the torque arm
i just saw the procedure. basically i need to unbolt the 2 bolts in the tranny to the drive line support, jack it to 80mm or something, then tighten them up. ill post exact procedure after the UK game. GO CATS!!! lets get 14-0!!!
So I dropped the tranny to the exact 80mm. Replaced the broken bolt in the transmission support. The vibration is still there
below 60mph in 5th. Anymore more suggestions?
is it completely loud if you're running below 60mph? it doesnt go away at all even if you're below or above 2000-2100 rpm?
by the way, you don't go faster than 60 mph during your break-in period?
cuz my clutch produce those vibrations, ONLY on 5th gear when im around 2000-2200 rpm, but there's no vibrations/sound when I'm above or below that rpm. But the sound produced is not that bad, compared to what you are experiencing It is only slightly louder than my ex-gf's vi-brator......lol
During my break-in period, I drive above 60 mph on the highway, and I just make sure that on every gear, I don't go beyond 3000 rpm.
Let's see. I am never in 5th below say 53. So it vibrates between 53 and 60 enough that I cannot use the rear view mirror. But smooths out completly by 61mph. I'm sure it's normal but doing the clutch myself I am just paranoid about every little thing.
i will keep you guys updated. My car is now in the garage untill the 2nd. Road trip to gatlinburg in the durango. When I get back, I will finish the break in. then I should never even be in that rpm range in 5th
I will not do a clutch job again. 1k is worth it. to me anyways.
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