SpeedFreak87

Hello all, this is my first post, I just bought my first Vette a few weeks ago and instantly noticed the massive driveline shake and hop when hard accel/burning out...definitely looking to fix this asap and with Pfadt being closed has anyone used the Hoosier mount? It looks identical to the Pfadt brace as far as I can tell, Any info would be helpful!

Thanks

martysauto

Buy better tires before you break something. I'll think you'll find most of us don't use that mount. Make sure your shocks and suspension are in good shape. Check out dte trans brace.

SpeedFreak87

Is there a specific reason not to use the mount? It seems like it would be a good investment to stiffen up the driveline and prevent damage to components

v98roadie

I am having the HPE mount installed this week along with a rebuilt 3.73 diff. I have already installed the tunnel reinforcement plate and that alone tightened up the car a lot. I'll let you know what I think of the brace once I have it installed and light 'em up.

SpeedFreak87

Ok thanks, keep me updated, I have a 2003 z06 thing bounces nonstop hoping to be able to install this myself over the winter if I hear it solves at least 50% of tranny shake

zeevette

That "shake" breaks expensive parts. I've got both the ECS trans brace, and the Pfadt diff. mount. My first differential twisted itself into garbage hitting 4th gear @ redline. (before the braces/Rick Kim diff.)

SpeedFreak87

How hard is it to install the ECS trans brace? I'm hearing weird noises when I shift from the rear, almost like the diff is moving forward and back against the trans?? Idk how else to describe it

Also how would you compare the Hoosier to the Pfadt mount?

martysauto

You have warning signs already! You should repair the cause of the noise first. I would take it easy until it's resolved.

SpeedFreak87

The best part about all this is when I bought it at a dealer three weeks ago I asked why it was making that noise in the back when downshifting and when going from 3, 4, 5 they said "we inspected this car fully it was the service managers car and there is no mechanical issues, that noise is normal 'driveline slop' when the car gets older the mounts weaken and you get some rattling when shifting, it's nothing to worry about"....I never thought it was normal but I've never had a Vette before and know nothing about this cars setup :/

zeevette

It should be fairly straight forward; just awkward with the TT installed. I installed my braces when I had the rear sub dropped to change out the diff. Real easy then. I don't know what the Hoosier one looks like, but assuming it's the same; I didn't like the way it mounted to the sub, metal on metal. I did two things different than most others; I cut a small strip of silicone intake coupler, to insulate the steel bracket from the sub, and I also spaced the large pads on the ends to snug up tight to the sub when installed. I got zero vibration that others have mentioned after the Pfadt brace. I like the ECS brace because it's much lighter than the DTE, although similar designs. I also removed the diff. dampener, as recommended by Pfadt.

BTW, I think your dealer is FOS; nothing should feel loose, except the tires hunting for traction. Also, tire spin is the starting point to most cases of drivetrain shake, AKA wheel hop.

SpeedFreak87

Here's the link with pics of the Hoosier version

http://hoosierpe.com/news/c5-differential-torque-limiting-brace-mount-available/

By your description I'd definitely need to drop the rear to get the ECS mounted then? No way to install with the sub and diff all mounted on the car?

And yes I also believe the dealer is full of it, I'm assuming he was trying to tell me that the noise was what gm calls Normal Backlash...I don't like the sound that's for sure

zeevette

No the trans brace can be installed w/o dropping the rear sub, but you have to partially anyway, to install that Hoosier brace. BTW, it's nearly identical to the Pfadt brace, so my advice works for both.

SpeedFreak87

Ok cool, thanks sounds like I'll be getting both of these soon. With the torque diff mount you still use the transmission mounts with it?

road pilot

I use both the Pfadt and ECS brace and they work well together.
I have a lot of hp to control.

Patches

I did the Pfadt and ECS as well on my current build.

I used some EPDM sheet as vibration isolators on the Pfadt bracket.

93Polo

Ed,

Did you use EPDM tape? I'm running a DTE brace, and Pfadt mount.

Edit: found more pics in the build topic.

SpeedFreak87

Where at on the bracket? Where the middle bolts to the trans crossmember?

zeevette

Yes; between the diff mount, where it contacts the cross member. Also on the ends of the brace, where the large pads contact the cross; shim them so they're firm to the cross. Some guys have had vibration problems after installing this brace, but I didn't.

Patches

If you look at the rubber shoe on the end of the Pfadt diff mount in the pic below, you'll see where I added the EPDM pad between the shoe and the crossmember. I put one on each of the two shoes.

SpeedFreak87

Ahhh yes I see it, the 1/8 inch or so piece of rubber under the bushing? Looks like a good fit