With the usual chatter about warping rotors I happen to notice in the main shop manual (GM) that the suggested torque for the front wheels is 89 lb ft. I was always told to torque to 100 lb ft. - which I have been doing.
Anyone else notice this. It was not in the spec section, but a section where they were giving instruction that included re and re the wheels. They stated to re-install the wheels and torque to 89?
Also, spark plugs called for 25 lb ft. Mine were in much harder than that. In fact one of the plugs must have been put in by Hercules! I was able to remove after much effort with a 1/2 inch drive ratchet!
Posted by blkragss02 (Member # 1801) on :
90-100 lb ft. should prevent most rotor warping
Posted by BrostalSS (Member # 1830) on :
Also, not abusing your brakes prevents warping. Dragging, them, hitting them hard to stop. Heat=Warpage.
I've never had problems with rotors warping and I don't even torque my lugs. I just hit 'em with my impact wrench to tighten them.
Posted by SS_CarGuy (Member # 2065) on :
I have the F-body shop manual for 2000 and it clearly states 100. Where did you see 89?
Posted by DanA_F99_1977 (Member # 118) on :
I am comfortable with 100 lbs. There has been lots of discussion about rotors and helping to prevent warping.
I would not just hit them with an impact wrench and I use them very hard at the track. There is a big difference between street driving and the track.
For the street, there are some basic precautions. When exiting the freeway and have to stop, use the E-Brake instead of holding your foot on the brake. With two pads pushed hard against a hot rotor, there is a potential for warpage by that alone.
Posted by Hawkeye (Member # 88) on :
quote:Originally posted by SS_CarGuy: I have the F-body shop manual for 2000 and it clearly states 100. Where did you see 89?
Section - 3-72 - Wheel installation says to tighten to 100 lb ft.
Section - 6 - 1815 - Wheel replacement after replacing exhaust system says to tighten to 89 lb ft.
GM Tech manuals. Hmmm???
Posted by Elie Garfinkel (Member # 1635) on :
FWIW, The instructions I have, read 100 and therefore I tighten to 95. (what could it hoit?) The previous comments about care are extremely important... as well as bedding in the pads and heat cycling the rotors properly when new. Following the proper cool-down procedure after hot lapping also contributes to maximizing rotor life, as well as using a "rotor-friendly" pad.
Best regardSS,
Elie
Posted by Bill Mason (Member # 1807) on :
quote:Originally posted by Elie Garfinkel: FWIW, The instructions I have, read 100 and therefore I tighten to 95. (what could it hoit?) The previous comments about care are extremely important... as well as bedding in the pads and heat cycling the rotors properly when new. Following the proper cool-down procedure after hot lapping also contributes to maximizing rotor life, as well as using a "rotor-friendly" pad.
Best regardSS,
Elie
Actually, under torquing the lug nuts can hurt. Torquing the lug nuts puts a pre-load on the studs. This pre-load has to be greater than the actual force that the wheels will ever exert on the studs. In this way, the wheel does not become unseated from hub as would happen if the force exerted by the wheel was greater than the force created by torquing the lug nuts on the stud.
Also, if the studs are under torqued and the wheel forces cause additional stretching of the studs you can lead to fatique issues which can lead to stud failure (breakage).
IMHO, it is better to err on the side of slightly over torquing than to under torque. My two cents.
Posted by Harry (Member # 1834) on :
quote:Originally posted by Hawkeye: Section - 6 - 1815 - Wheel replacement after replacing exhaust system says to tighten to 89 lb ft.
GM Tech manuals. Hmmm???
Would it be possible that this section deals with the v-6 models and that they are talking about steel wheels? I think that the torque setting for steel wheels may be lower than that for aluminum wheels, but I'm not sure.
Posted by DaddySS (Member # 848) on :
I always torque them to 50, then to 100, pump the brakes on long stops, try to anticipate stops (with my automatics) and downshift to add engine braking with the manuals, and have never had a warped rotor.
Posted by poSSum (Member # 119) on :
I take mine to whatever torque a 9.6 volt cordless generates, drop the car from the jack, then roll it forward and backward a couple of feet to ensure there is no side-loading from coming down off the jack. Then I torque to 40 - 70 - 100. With autoX, I end up changing the tires back and forth at least a dozen times a season.
I replaced the rotors and pads at about 55,000 miles and was shocked with how much life was left in the original pads and the rotors were still straight. A lot of driving was highway, but I figured autocross and drag racing would have used up more brake.
quote:Originally posted by Hawkeye: Also, spark plugs called for 25 lb ft. Mine were in much harder than that. In fact one of the plugs must have been put in by Hercules! I was able to remove after much effort with a 1/2 inch drive ratchet!
If you haven't changed them previously, they may have been partially siezed rather than overtorqued originally.
[ 11. March 2004, 10:00 AM: Message edited by: poSSum ]
Posted by mhayman (Member # 146) on :
I have always torqued mine to 100 ft. lbs. I do 50-75-100 increments.
The sad part is that I have had bad luck with the warpage issue on both my 98 and my 00. I had never had brake issues with ANY of my cars before I had the Camaro. I don't consider myself to be hard on brakes at all. I drive reasonably and don't race at the track. So I have been hard pressed to figure out the cause of this warpage.
After buying the Autozone replacements and not having one problem with them, I have come to the conclusion that it is GM's rotors, not driving style and not torque. While getting your brakes red hot while at the track and then sitting with your foot on the brake or torquing the lugs to 250 ft. lbs. will (and should) damage your brakes, I REALLY have a tough time believing that my exiting the freeway from 70 MPH and sitting at a light with my foot on the brake or torquing the lugs to 95-105 ft. lbs. will do major damage. What about when I drive through a puddle of water? Why are the rotors THAT sensitive? I have never known any other car to have rotors as sensitive as these.
Everyone on this board takes pretty good care of their cars. And a lot of us go to extremes to take care of the rotors only to have them warp anyway. I don't want to sit at a light with my E-brake on, or have to downshift and engine brake, or not be able to wash my car after I drive it just to keep the rotors from warping. I never did those things with any other car and never had a problem and that's why I just replaced them with an alternative that has worked well so far.
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The previous comments about care are extremely important... as well as bedding in the pads and heat cycling the rotors properly when new. Following the proper cool-down procedure after hot lapping also contributes to maximizing rotor life, as well as using a "rotor-friendly" pad.