Rebel_Bowtie

Hey guys -

I have a real bad vibration in my car that you can feel pretty much from 2000 RPMs up. I recently put in a new transmission with a TCI Flexplate and TCI Stall, and have had a custom driveline made to fit the car, and had all wheels balanced.

My biggest question is... The TCI Flexplate came with a metal sleeve that fits over the Stall and into the Flexplate. When I tried to install with this bushing my tranny housing was 1/4 inch off the motor, and when I called TCI they said that it was only need if I wan't using a TCI Stall. I've sinced called TCI 3-4 times and each time got different answers as to when this part is needed. I've been told it's needed on all LS1/tranny, only with an LS1/TH350 or 400, only when used with a TCI stall.

Does anyone know what this piece is for?

Any other ideas on what my vibration is coming from? It occurs in Park/Nuetral and in gear, sometimes I can put it in Nuetral while driving and it dies down until I rev it up, it's a pretty consistant sound, Sometimes it seems to get better underload and sometimes way worse.

Thanks for any help... I've already spent thousands from shops telling me it's this or that and it's still not fixed!

Turbo Tech

iTrader: (2)

If you can notice it in park is must be a balance issue. Be sure they sold you the proper flex plate because some are externaly balance. Not sure what a TCI stall is. I have personally has converter balance wrong and had the same issue. If you remove the flexplate be sure to have it neutral balanced. Any engine/machine shop should be able to do this. The convertor can be checked at Casey's Transplant here in Tacoma.

Rebel_Bowtie

The balancer was my first thoughts too, but I've been told the converter can cause the same issues in Park/Nuetral?

The TCI Flexplate (399753) I have has no external weights on it. The first flexplate I bought that was supposed to fit had external weights and a smaller diameter crank hole.

Can Casey's Transplant rebalance my convertor or only able to tell me if it's off-balanced?

jewbacca

iTrader: (5)

I know, off topic, but whats up Matt. This is Cabe. How are you doing.

Now, about the vibration. You said that yoiu had a custom drive shaft installed. Aare you sure it was balanced correctly. Maybe they didn't get it right.

Rebel_Bowtie

Hey Cabe, I'm doing good! How you?

I did have him take the driveline off and rebalance it after installing it, and it was dead on.

I'm ordering a new ATI Super Damper, so hopefully that will fix the problem.

Turbo Tech

iTrader: (2)

Casey's would be able to check the balance of the converter. The driveshaft would not be a issue if you feel the vibration when the car isn't moving.

WAHUSKER

iTrader: (4)

Tranny housing 1/4" off the motor? Stacked the converter maybe?

Rebel_Bowtie

Yeah that was with the sleeve that came with the TCI Flexplate. I have found out that this sleeve is in fact only for use with a LS1/TH350-400 combo. It bolted up fine without the sleeve, but I have this vibration.

I'm new to the term "Stacked the Coverter", what does this mean?

If the converter is off balance, is there a place that can rebalance it or do I have to get a new one?

Would it be a safe practice to unbolt my convertor with the tranny still in place and run the motor? My thoughts are this would give me a definate answer on if it's coming from the motor or the converter, but I'm not sure if there's enough room to do this without the converter sliding back into the flexplate.

Thanks again for the help!!

NWDragRacer

This would be an excellent test.

You should have room. I would wire the converter back so that there would be no way for it to move back into the flexplate.

WAHUSKER

iTrader: (4)

4L60E converters are finicky to install correctly. You have to push & turn (clunk #1), push & turn again (clunk #2) & push & turn again (clunk #3) to get them in all the way. Or you end up "stacking the converter", meaning it isn't lined up properly & you destroy the tranny (wipes out the pump).

One of the tell-tale sings is the bellhousing doesn't mate with the block like it should.

Disclaimer: I am NOT an expert on the subject - never done this, but have heard the stories

Rebel_Bowtie

Oh right, I've just never heard the term "stacking the converter". I've done several convertors in the past and was aware of the 3 clicks/clunks to get it all the way seated on the input shaft. The only reason the bellhousing had the gap was due to the sleeve that TCI sent with the Flexplate (which I've since found is only for use with TH350-400 tranny). Without the sleeve it bolted up fine. Thanks for the terminology lesson, ideas, and help!