Tranman324

I have been getting a annoying vibration when I decelerate in 4th gear around 2K-2.5K RPM. It sounds like a bunch of bees are in my transmission when I let off the gas. It does it in 3rd too at about 2K, but not as loud as in 3rd.

I originally thought it was my stock drive shaft. I tried turning it 90, 180, and 270 degrees; no luck. I then had it rebalanced and the carrier bearing inspected. The bearing was good, but the balancing didn't fix the problem.

So I caved and bought this:
1-Piece Platinum Driveshaft S13
THE PROBLEM IS STILL THERE. Now instead of the buzzing inside the cabin when I decelerate, that vibration resonates in the new steel drive shaft and makes hella noise outside of the car when I let off the gas. It sounds like something vibrating on a sheet of metal. No, nothing is hitting the drive shaft and nothing else is rattling under the car. There is also no play. I also tried the 90, 180, and 270 degreed positions again.

From what I've been gathering through researching about this problem, the SR is prone to deceleration vibrations and a sprung OEM clutch is made to damper this vibration to keep it from resonating through out the car. So OEM is the way to go to keep this from happening. With my Spec sprung clutch, these sh!t heads sold me a clutch with springs that are either too soft or too stiff to dampen the vibration of my motor. This problem is supposedly more prevalent in tougher clutches like 6 puck clutches. Am I right?

So this is what I have that could be related to the problem:
- 93 S13 Hatch
- S13 Redtop SR
- Z1 Motorsports Stainless 1 piece Drive shaft
- Q45 Viscous LSD
- Spec Clutch (Forget what kind, I think the second step from their base model clutch)
- Koyo T/O bearing
- Nismo Tranny Mount
- Aluminum Sub frame inserts

So the thing I will NOT do in the near future: Pull the transmission and replace the clutch in HOPES i find the a clutch with the right springs. EFF THAT MESS. I'm sure many people would sympathize with me.

Now my next idea to subdue the loud metal rattling from my drive shaft is to fill my drive shaft with "Great Stuff" foam or the like and have it rebalanced. Through A LOT of digging I found that this has been a fix to some GM cars and 4x4s. I know this won't fix the problem. My goal is to minimize the noise without dropping the transmission again. Anyone heard of this before? Any other thoughts? Please discuss.....

Blues13

That sounds a lot like what I'm experiencing.. There's this loud vibration/buzzing noise when coasting in gear. My S13 is already loud, so I didn't notice it at first, but either I'm getting old or it's getting louder. It only happens while in gear and coasting.. on the gas and in neutral seems normal.

I haven't had a chance to take a look at it as I've been busy with work, but it's starting to drive me crazy. The car feels like a giant tuning fork when it does happen.

I also have a SPEC clutch, stage 2 plus. This is the first time I've heard about this with this clutch, so I'll start taking a look into it too.

My setup that could be related to the problem:
90' 240sx Fastback
S13 SR Blacktop
OEM VLSD
Spec stage 2+ clutch
Toda Lightweight Flywheel
Tanabe Sevens Coilovers
Rear tires are worn, needs replacing - Fronts OK

Please let me know if you find the problem!

KiLLeR2001

I also have deceleration vibrations, but I'm pretty sure its transmission related. The reason I say this is because I had a small oil leak in my transmission, so I decided to buy some of that Lucas transmission fix, I pour some in, and immediately I noticed that that vibration had gone away. Unfortunately a few days later it was back again. But I may try using a different transmission oil. I'm using Redline MT90 now, but I'm seriously considering Amsoil, just to see what happens.

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