Bilstein Rear Shock Install
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,113
Likes: 35
From: LaUgH, mOrE!
Bilstein Rear Shock Install
I am replacing my Bilstein rear shocks with standard Bilsteins on my '96 LT1. The Helm manual says to "tighten the shock absorber upper bracket retaining nut to 26 N-m." If I do this, the top retaining nut compresses the upper grommet so that it spreads too flat to fit back into the hole of the frame where it mounts.
How tight is tight enough so the grommet will not spread too flat?
How tight is tight enough so the grommet will not spread too flat?
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
I believe they are referring to the bolts that secure the bracket, not the stud nut on top of the shock. Not sure of the torque but I usually
using a self locking nut, or double nut, and tighten it enough to slightly
distort the bushings. My FSM is out in the garage, I can check it in the morning if need be, let me know.
using a self locking nut, or double nut, and tighten it enough to slightly
distort the bushings. My FSM is out in the garage, I can check it in the morning if need be, let me know.
Race Director
Joined: Jun 2004
Posts: 13,957
Likes: 706
From: WI
That happened to mine to, I ended up buying some poly bushings to replace that soft rubber. I did run the car fine by tightening the rubber down just so it would fit. If I remember right, it called for 20 ft/lbs.
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,113
Likes: 35
From: LaUgH, mOrE!
Thanks for the responses. The Helms manual recommends the top stud nut be tightened to 26 N-m (19 ft-lb). Right now I have the self locking nut tightened so that about 9/16" of the end threads showing. The grommets are compressed, for sure, but just fit into the body frame hole. Ya think it's good enough to stay put?
Last edited by G-Sting; Apr 19, 2007 at 08:00 AM.
Le Mans Master
Joined: Jan 2006
Posts: 6,564
Likes: 6
From: Woodstock Georgia
Thanks for the responses. The Helms manual recommends the top stud nut be tightened to 26 N-m (19 ft-lb). Right now I have the self locking nut tightened so that about 9/16" of the end threads showing. The grommets are compressed, for sure, but just fit into the body frame hole. Ya think it's good enough to stay put?
Yes
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Thanks for the responses. The Helms manual recommends the top stud nut be tightened to 26 N-m (19 ft-lb). Right now I have the self locking nut tightened so that about 9/16" of the end threads showing. The grommets are compressed, for sure, but just fit into the body frame hole. Ya think it's good enough to stay put?
Race Director
Joined: Jun 2004
Posts: 13,957
Likes: 706
From: WI
Thanks for the responses. The Helms manual recommends the top stud nut be tightened to 26 N-m (19 ft-lb). Right now I have the self locking nut tightened so that about 9/16" of the end threads showing. The grommets are compressed, for sure, but just fit into the body frame hole. Ya think it's good enough to stay put?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Le Mans Master
Joined: Sep 2003
Posts: 5,874
Likes: 0
From: Littleton CO
I may be exposing myself a bit here... but how does one measure torque in the first place, when the shock stud needs to be retained during tightening with a hex key in the end? Is there a different style of torque wrench that is suitable in this case?
I ended up just following the type of advice that has been given here instead of asking around and then buying another tool.
I ended up just following the type of advice that has been given here instead of asking around and then buying another tool.
Le Mans Master
Joined: Sep 2003
Posts: 5,874
Likes: 0
From: Littleton CO
Changing yours soon? The Z51 shock comes with poly mounts, the standand does not. I ended up ordering poly to replace the rubber.
Le Mans Master
Joined: Sep 2003
Posts: 5,874
Likes: 0
From: Littleton CO
BTW, my Bilstien Z-51 (or Sport as ordered via aftermarket) shocks came with rubber mounts, not poly. I'm sure I recieved the correct Bilstien part numbers, as I checked incessantly before my order.
Race Director
Joined: Jun 2004
Posts: 13,957
Likes: 706
From: WI
Did the swap a few weeks ago already. Searches turned up at least a few other threads here where the 19 ft-lb appeared to compress the rubber too much, so I decided that it would be OK to go by feel. I'm pretty sure that I got to at least 19 ft-lb, and the grommets showed just a slight bulge. One worry I had was that overcompression may cause premature wear.
BTW, my Bilstien Z-51 (or Sport as ordered via aftermarket) shocks came with rubber mounts, not poly. I'm sure I recieved the correct Bilstien part numbers, as I checked incessantly before my order.
BTW, my Bilstien Z-51 (or Sport as ordered via aftermarket) shocks came with rubber mounts, not poly. I'm sure I recieved the correct Bilstien part numbers, as I checked incessantly before my order.
http://forums.corvetteforum.com/show....php?t=1626631
at post #14 about them coming with poly. There is so much squish in those rubber mounts, it didn't seem good for track use.
Thread Starter
Burning Brakes
Joined: Jun 2005
Posts: 1,113
Likes: 35
From: LaUgH, mOrE!
Both rears are replaced with new standard Bilsteins now. By compressing the upper grommet to slightly less than the upper washer diameter it left about 9/16" of thread exposed. This seemed to match exactly the OEM Bilsteins I replaced. Runs and drives great again. Thanks for the comments.
