I wrote to fluidampr about a 6.5L dampner and they think the 7 1/4" or 8" for the 396 gasoline engine should work. I'm willing to try one out but I'd like to hear some feedback.

No go. The 6.5 is externally balanced in the damper. Must have the required damper for the engine.

What would it require to work? They offered their spec sheets for the two sizes and ask me figure it out.

I believe the 396 and 454 were externanally balanced, but the counter balance must be the same as the 6.5. I really doubt they would be the same. How to make it work? I would think the orginal and the new one would have to go to a Master engine builder with a good balance machine. I use to balance race engines and the like.

I am surprised to hear that their reply was to 'Try and figure it out'.

I thought Fluidampr was a respected company with a good product. They were supposed to be coming out with a balancer specifically for the 6.5. What happened?

For the record, I have used their balancers for over 15 years. Very nice product.

I don't know if the 6.5 is Internally or Externally balanced, but the 396/427 were definately internal. The 454 was external.

I have an old 454/External Fluidampr laying around. You need to measure the crank snout on the 6.5. Even then, I don't think I would bolt one on and be a test mule.

I talked to those guys a couple of months ago and they said they were going to have a 6.5 specific application by the end of this year. I even posted about it here (http://www.dieselplace.com/forum/showthread.php?t=6093&highlight=fluidampr). I just noticed the link is also at the bottom of the page. I looked at their site and found applications for the usual suspects, but no 6.5 TD.

Anyways, I think I'll do the gearset upgrade and timing if they make one available. If the damper/balancer/pully is what I think it is, I shouldn't have to go near that part of the engine for a long time.

6.5L is externally balanced - big half-moon chunk in the balancer hub

I never thought about calling my buddy........J.C., owner of ATI automatics and balancers. We raced karts together as kids......guess I'll send him my new in the box balancer and see if they can figure the imbalance figures on the stock balancer.

This is their response to external balance requirement.


Our 6.6 DuraMax Fluidampr will be
externally balanced.

The information given to us about the 6.2 and 6.5 is evidently wrong
since 720121 and the 800101 are internally balanced Fluidamprs. We have
always advised people that we do not have a Fluidampr for the GM 6.2 and
6.5 Diesels, so thankfully we have never mislead anyone.

We appreciate your valued information and we will attempt to resolve
this issue.

Fred Roland
Fluidampr / Vibratech TVD
(716) 592-1000