Opinions vary, but they were installed to damping the vibrations on convertibles only. (lack of roof for stiffness) GM's way of solving a problem. Some like'm some don't. Regardless, in good condition they are worth good money. BTW they are called "cocktail shakers". They add about 100 pounds extra to the car. Unless your building a 1/4 miler, you wont notice too much of a difference. I say leave'm in!
I see many convertibles without them, but they have always been in my cars. I believe someone here without them did not notice any issues.
If only one is missing in the front, it's possible that the front of your car may not sit level due to the weight only on one side.
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold
Rear shakers are 50lbs each...Fronts are 25lbs. I drove my '67 for two years before I installed a salavaged set from a....similar GM product. They did make a difference in ride quality.
Run a search here on "shakers" (the common nickname all use for the Pontiac part "vibration dampener") and you will get lots of info on them. Note that their functionality is the same but mounting differences between years, Camaro vs Firebird, and front and rear.
There was a guy over on a Camaro forum who cut one open to show the weight and springs that are suspended in the oil. Maybe someone here has saved that picture?
67 Firebird and Camaro shakers are the same. '68 Firebird shakers will not fit a '67...at least the fronts don't. I'd assume that 68 Camaro and Firebird shakers are also the same.
'67 and '68 rears are also different. I think '69's are different as well. For sure the fronts are different for '69.
I used to be indecisive. Now I'm not sure. I feel like I am diagonally parked in a parallel universe. 1968 400 convertible (Scarlet) 1976 T/A - 455 LE (No Burt) 1976 T/A New baby, starting full restoration. 1968 350 - 4 speed 'vert - 400 clone (the Beast!) 1968 350 convertible - Wife's car now- 400 clone (Aleutian Blue) (Blue Angel) 2008 Durango - DD 2008 GXP - New one from NH is AWESOME! 2017 Durango Citadel - Modern is nice! HEMI is amazing! 1998 Silverado Z71 - Father-daughter project 1968 400 coupe - R/A clone (Blue Pearl) (sold) 1967 326 convertible - Sold 1980 T/A SE Bandit - Sold
My rears were missing when i bought the car.Cannot offer how the ride was with them but i can say that the ride without them was not bad but my suspension in the rear is of decent quality parts.
David
http://FirstGenFirebird.org/show/closeup.mv?CarID=571 If i don't get this car back on the road soon i'm gonna go postal! On a quest for FGF knowledge 1968 Pontiac Firebird Convertible 1969 Oldsmobile Cutlass "S" Convertible *Sold*
I left mine in just because Detroit put them there. I have been asked many times when the trunk was open "What the hell are those things". Good conversation starter if nothing else. I didn't realize there was oil in them. Thought it was a weight suspended with rubber. Guess you really do learn something everyday like my mother always said.
They're needed, GM had them there for a reason, I've driven with them and without and they do make a difference. Plus they add value to the car. Any good set on Ebay goes for several hundred dollars. Subframe connectors don't add value...but I'm more of a purist with a slightly modded mind!
They're actually filled with trans fluid. GM subletted a company to manufacture them and the showed up at the factory empty and then were filled. I read the tranny fluid is better for the reason they intended, it's a more stable fluid.
![[Linked Image from i601.photobucket.com]](http://i601.photobucket.com/albums/tt95/920-680-1902/firebird/Photo_2006_1_29_22_27_15_edited_edi.jpg)
