LS1ROC

iTrader: (12)

Has anyone ever heard of this happening? I recently sent my converter back for the free restall, and now I have a horrible vibration/pulsating problem at around 2100 rpm or so. It seems to be less noticeable in overdrive, but its still there. I've tried different driveshafts,rearends, new u-joints, tires,pinion angle to no avail. The car will still shake pretty good at the same rpm in park or neutral, and all was fine before. I did swap my LS1/4l60E from my first camaro into the current car because I didn't want t-tops, with the only difference being that I used the Spohn motor mount/crossmember kit instead of the S & P adapter plates. Anyway, I'm ready to drive it off a bridge it's so bad. Please help! Sean

JS

iTrader: (4)

Dude I am getting the came thing..
I think the verter needs to be clocked.

Sometimes when u move it a 1/4 turn and then bolt it back up it goes away.
I'm gonna do mine this week...

I do have YTP going in the car soon though but I still wanna see if this is whats cuasing that.

LS1ROC

iTrader: (12)

Thanks man. There is hope. It would be great if that would fix it. let me know how it turns out.

CrimeSScene

iTrader: (9)

Well, I just posted about mine too, asking the same question. I've heard the same thing about turning it one bolt hole. I'm gonna give it a try too. I didn't really know how to describe the vibration exactly, but pulsating is a very good word for how it feels. Let me know if either of you have any success turning it one hole.

Rockit_GTO

I have the same problem only around 1500 to 1800 then 2500 and up. Tried turning the converter and still the same problem.

My installer pulled the conveter off and then reved the motor and still the same problem. Our guess is the motor is out of balance and the smaller converter is bringing it too light. The larger stock converter reduces the vibration (more fluid and more converter to soak up the vibration).

CrimeSScene

iTrader: (9)

Probably gonna be my problem too. I had a little vibration at those rpm's with my stock converter, but they weren't noticable at all unless I reved it in neutral. I'm still gonna try turning my converter though. It's worth a shot. Hell, I already bought all my parts to convert to an M6 if this doesn't pan out, but It may actually get worse with no converter dampening effect at all. This sucks.

RevGTO

iTrader: (12)

I have a similar vibration 2100-2300 in 3rd with the stock converter. It existed when I had 2.73's, so when I changed to 3.42 gears, with carrier and driveshaft (aluminum, new U-joints at both ends, balanced), I thought that might be the end of it. Well it is still there, even though there car is at a different speed with the new gears - thus not a wheel/tire issue. It feels like it is coming from the back of the car, though I have been to theorize that it is an engine balance issue. Either that, or the pinion angle is off - but I doubt it on a pretty much stock car. I'm open to ideas also ...

RevGTO

iTrader: (12)

Forgive the bad typing: "there car" and "have been to theorize" - what was going on in my head?

Rockit_GTO

Update: Mine has been out the dealer for two days now for this problem and they still cannot determine the cause. Why can't they just admit the motor is out of balance?

I'll keep you posted.

PSU_Engineer

Oh man am I releived. I thought I was the only one with this problem. I still have the stock converter in the car. When I changed to 3.42's like RevGTO it did the same thing that he mentioned. The "60mph butt massage" is only apparent when I'm in Drive, not OD.
So I'm releived to have found the problem, yet worried that it is not the converter that is out of balance, but the motor like you all suggested. Although this is a good excuse for me to start budgeting for a APE 409 BALANCED short block

Tony

CrimeSScene

iTrader: (9)

Well, I still have my stock warranty for another 5 months, but to redeem it, it would mean having to put everything back stock, just to take it into the dealer. I ain't pullin the damn cam and converter out without a guaranteed new engine going back in and somehow, I just don't see it. Especially since I've already had them put a new engine in when I had 400 miles on the car. I'm probably gonna try turning my converter one hole this weekend, and if that doesn't work, I'll just go ahead and put the M6 in the car and see if that changes anything. Guess I'll just have to live with it if that doesn't fix it cause I can't put any more money into my car right now.

LS1ROC

iTrader: (12)

I like the idea of the motor being out of balance, but I didn't change anything on the motor at all, and I drove the other t-top car for 1.5 years with no problems. This is really perplexing. I might just have to start taking things apart. I even bought the BMR torque arm and adjusted the pinion angle to no avail. Hopefully one of us will run across something and we can all be happy. Thanks for the ideas and good luck to all.

RevGTO

iTrader: (12)

I was thinking about getting a torque arm, but I've heard a number of times now of guys who have had not success with that for this problem. People also will insist on wheels and tires, but it will be vibrating away in third, and when I shift to fourth it'll be smooth as silk. The other odd thing about this is that sometimes it is worse than others. Sometimes it is barely noticeable; other times it's really annoying.

CrimeSScene

iTrader: (9)

Noticed the same thing here. Sometimes, I can't tell that it's vibrating at all and other times, it feels like something is about to come apart. I can tell that it's RPM related vs. Speed related, but other than that, there seems to be no real rhyme or reason to it. One thing that I have noticed though is that mine often seems the worst when my car is cold and I'm just beginning to drive at a slow speed. Also, the faster I take off, the less vibration I get.

IRONMAN

I have the same type of problem as well.I got a Yank SS 3200 installed 2 weeks ago.Now,between 1000 - 1500 rpm , 25-30mph, and in 2nd gear there is this loud vibration/rattling perhaps grinding comming from the center of the car right where the tranny is.It happens alot while crusing in traffic.As I apply the gas slightly is progressively gets fater and louder then as soon at I go above 30mph,it`s gone! It especially happens while going up a slight incline.Again,it only happens at that range.Other than that,it`s great.It is driving me out of my friggin mind and I just hope that it is an easy fix and more so that I haven`t screwed my tranny driving it like that.It`s at the shop that installed it as I speak.They have never heard of anything like that before.Hopefully they will find out what the hell is going on so I can inform those that are still at a loss.This started RIGHT AFTER the TC install.My 2001 SS has 33,000 miles,I have had it since Dec 5,2000 and for the past 1 1/2 years,I only drive it like 2-3 times per month.I know my car and I don`t want anyone telling me that the exhaust is rubbing something!

97SilverBullet

Hi everyone, I am new here. I have a completely stock automatic lt1 ta and I was just on the verge of ordering a vigilante tc 3200 stall. What is this vibration contraversy? I know my car has a slight/moderate rumble when i get up to 60-80 and let off the gas a little. Is this what you all are referring to or is it something much more agrevating? I'm pretty bad off with mechanics so can you please be a little specific while explaining.
Thanks, Corey

JS

iTrader: (4)

Mine was resonance in my exhaust.
I opened the cutout and now its gone....

For some reason my car hates my custom dynomouth single exhaust.
I guess its so close to the tq arm,driveshaft,poly mount and a k-member w/tube a-arms and rod ends it all vibrates alittle more than the stock stuff.

RevGTO

iTrader: (12)

Again, as far as I know mine has the stock converter, so it's not related to any installation. It did it with the 2.73s and after I installed the 3.42s - at the exact same rpm in 3rd gear only. It is a vibration that's not really accompanied by any noise - worse when I let off the gas. I've theorized that it's worse when the car is cold, but then again, this morning, I could hardly notice it. Out of balance flexplate, bad tranny mount, exhaust resonance (doubtful) are some of the possibilities I'm thinking of. It is just plain strange.

97SilverBullet

thank you both. I am sorry for your inconvieniences but happy for my uninvolvement. I wonder though, do any of you think the vigilante mess with my lt1 engine?

97SilverBullet

I am pretty scared of getting a converter now. In your honest opinion, do you thing it is wise to trust a vig 3000 in a stock LT1? if so, what other arrangements must I make to keep the tranny safe and the rest of the car?