Weird Grommit on Flywheel Bolt?

So Im looking for somthing to use to replace this "grommet" because the dealer cant get it..

Heres the flywheel bolt:
http://img.photobucket.com/albums/v234/gpchris/6-Speed%20Swap/DSCF0302.jpg


And Here it is without the rubber washer/grommit thing
http://img.photobucket.com/albums/v234/gpchris/6-Speed%20Swap/DSCI0334.jpg


Is there a place that sells these things?? The bolts are from a 2006 pontiac g6. Any help would be appreciated!


Edit**
They are used to keep the flywheel tight while tightening the bolts. The hole in the flywheel is bigger than the threads of the bolt..

I made the grommit out of a "screw cover" i found at the hardware store.. Do you think this is a good idea? The grommit is only used to keep the bolts straight while torqueing.. So if they burn up it wont matter cuz the flywheel will be tight.

http://img.photobucket.com/albums/v234/gpchris/6-Speed%20Swap/DSCI0348.jpg

[quote=gpchris95]I made the grommit out of a "screw cover" i found at the hardware store.. Do you think this is a good idea? The grommit is only used to keep the bolts straight while torqueing.. So if they burn up it wont matter cuz the flywheel will be tight.


the bolt should have been designed with a shoulder to match the flywheel hole...this grommet is probably used to protect the flywheel from being worn by the bolt threads...the lock material will keep the fasteners from loosing and the only issue could be the shoulder material may effect the torque values...

I would not use the shoulder material, this may be used only as a factory requirement..on the assembly line...

sooo should i use my sh*tty grommet?

sooo should i use my sh*tty grommet?

no..... the idea you had is creative but since the dealer does not have this item ,, as I stated, it must be some factory aid in installation...use of this may cuase the fastener to loosen,, this would not be good ...get torque wrench and torque to the proper spec...you should be ok....if these bolts loosen you will usually hear a clunk type of noise when shutting down the engine..

You may have to buy a new set of bolts to get the grommet. However, you should use the GM grommets. They are in there for a reason and your home made items may not be compatible.
IMO it's not such a good idea to start re-engineering a harmonic balancer since a bad/loose balancer can break a crankshaft requiring a major repair.

You may have to buy a new set of bolts to get the grommet. However, you should use the GM grommets. They are in there for a reason and your home made items may not be compatible.
IMO it's not such a good idea to start re-engineering a harmonic balancer since a bad/loose balancer can break a crankshaft requiring a major repair.


those bolts are new the dealer did not have/know of any ..shoulder material .....


do you have a part number for these grommets???

ummm my engine is INTERNALLY BALANCED! That means the flywheel and "harmonic balancer" are neutrally balanced and do not have any weights or anything to help balance the crank.

And no GM does NOT have the grommets.. I checked with a couple diff dealers and a freind who works there. I ordered the bolts from gm and they did NOT come with the grommet.

Straight from gms computer
http://img.photobucket.com/albums/v234/gpchris/9-5-20089.jpg

Hmmmm....... perhaps there was a running change in the balancer bolts.......

Ask the dealer if there has been a technical service bulliten (TSB) on this car and the bolts. It's possible they have changed the balancer and/or bolt design.
A TSB may have a recommendation about the new parts that should be used.
TSB's might also be available on-line.

[quote=gpchris95]ummm my engine is INTERNALLY BALANCED!


I don't know much about your vehicle but what I found out yesterday was the flywheels crack ....this may have caused the cracking [shoulder material] and now this has been discontinued...

as I have over the years seen ,, the flywheel bolts are not a big deal they are simply a very hard bolt that with proper torque and installation last the life of the engine and beyond...

hmm.. Im worried about flywheel alignment.. what if its a couple degrees off? It shouldnt throw off balance right?

no TSBs for it

Are these grommet things actually used to align it? If you use bolts without the grommets does it move? I've never come across anything like this.

hmm.. Im worried about flywheel alignment.. what if its a couple degrees off? It shouldnt throw off balance right?


the flywheel balancing is not effected by the position of the mounting...the bolts properly positioned and torqued is all that is required...

Are these grommet things actually used to align it? If you use bolts without the grommets does it move? I've never come across anything like this.

Well it has an alignment ring in the center but the holes in the flywheel are somewhat bigger than the bolt's thread. So basically when the bolts are on but not tightend the flywheel will be able to turn a couple degrees. However when the grommets are in the flywheels wont move.

Well it has an alignment pin in the center but the holes in the flywheel are somewhat bigger than the bolt's thread. So basically when the bolts are on but not tightend the flywheel will be able to turn a couple degrees. However when the grommets are in the flywheels wont move.

whenever two metal plates are bolted together, you need to allow for metal movement . if it fits tightly it will crack....also there is a lot of metal stress in this area. the metal if not allowed to flex, expand it will damage the flywheel..


that shoulder material once again was probably dropped because of this ...


If you have all day to kill on the telephone it is possible to contact GM and get a enginnering answer to your problem maybe? they may not answer it , because they sometimes keep secrets from vehicle owners ....lawsuits...

How are you sure that they stopped using the grommit?

How are you sure that they stopped using the grommit?


I was wondering If YOU called GM tech to find out whats up on this bolt shoulder material...


My position is this material is unnecessary, as this is the first time I ever seen such hardware used in a flywheel mounting..


so were are you at concerning this project? did you call GM?

gm techs said they cant find any info on it..

gm techs said they cant find any info on it..

good because, that is what I believed to be correct, after checking this out....

so where are you on this task..?

whenever two metal plates are bolted together, you need to allow for metal movement . if it fits tightly it will crack....also there is a lot of metal stress in this area. the metal if not allowed to flex, expand it will damage the flywheel..

This is only true if they are subject to heat AND one plate is a different material or one plate gets heated more than the other.

It is not true in most cases.

This is only true if they are subject to heat AND one plate is a different material or one plate gets heated more than the other.

It is not true in most cases.


thanks for that info.. perhaps you can direct us to where it is listed as this application requires this part possibly...?


on a fly wheel the metals may be different in composition ..of/or the mating surface may be of such constuction that it willl move at a different rate..

normal operation will cause the transmission to get much hotter than the flywheel...

thanks for that info.. perhaps you can direct us to where it is listed as this application requires this part possibly...?

The exhaust manifold is your best example. The difference in temp between that and your cylinder head means the manifold must either flex to keep the ports aligned or slide to let the head and manifold grow at their own different rates.

I haven't seen a flywheel setup that requires different expansion rates, but I haven't seen that many.

The exhaust manifold is your best example. The difference in temp between that and your cylinder head means the manifold must either flex to keep the ports aligned or slide to let the head and manifold grow at their own different rates.

I haven't seen a flywheel setup that requires different expansion rates, but I haven't seen that many.



on the head / exhaust manifold the parts slide on the surface of a gasket so as to prevent cracking....what happens when the temp goes above spec temp..???? this can no longer slide then it stress the metal over time it cracks...aluminum is very brittle...steel is more malable...can take more stress..


flywheels must flex....temps and torque are a factor...that is why if not properly installed and torqued the area is susepible to failure..

on the head / exhaust manifold the parts slide on the surface of a gasket so as to prevent cracking....what happens when the temp goes above spec temp..???? this can no longer slide then it stress the metal over time it cracks...aluminum is very brittle...steel is more malable...can take more stress..


flywheels must flex....temps and torque are a factor...that is why if not properly installed and torqued the area is susepible to failure..

The exhaust manifold will only stop sliding when it reaches the limits of the bolt hole clearance. Material expansion with heat is roughly linear (10% more heat, 10% more movement etc).

Aluminium is far from brittle. Head over to www.matweb.com and look up the various grades of common aluminium. Amoung the test results they list are elongation at break.

The exhaust manifold will only stop sliding when it reaches the limits of the bolt hole clearance. Material expansion with heat is roughly linear (10% more heat, 10% more movement etc).

Aluminium is far from brittle. Head over to www.matweb.com (http://www.matweb.com) and look up the various grades of common aluminium. Amoung the test results they list are elongation at break.

I don't know how old you are ....but in the old days antifreeze was no big deal with cast iron heads and a very heavy thick steel block....with this setup overheating of an engine caused no serious damage...let it cool down add water and your good again..

today this aluminum is a very fragile componet metal ...the expansion is far greater than steel/cast iron and as a result large movement holes are required... also many head gasket replacements require that the head bolts be replaced ...this is because of this aluminum expanding so much..


steel is much stonger than aluminum ....it also retains its shape better than aluminum which distorts easy....


the only reason aluminum is used is because of its weight and the ability to conduct heat from the engine..but the side effects are shorter engine life especially if the thermostat sticks just one time...by by engine..

since this is 2008 and most of us know that a cool engine will be a happy long lived one..

the aluminum that CAN be used from other sources , is much better than what the auto manufactures use..also gasket materials..

the tests of aluminum under high combustion temps will show that this metal is not very stong and will crack...and as a fact many have had this occur to them..with just running the vehicle slightly hot ...


on this flywheel bolt I would be very surprised to find that this spacer is required...especially from what we all know now..about this issue..

I don't know how old you are ....but in the old days antifreeze was no big deal with cast iron heads and a very heavy thick steel block....with this setup overheating of an engine caused no serious damage...let it cool down add water and your good again..

today this aluminum is a very fragile componet metal ...the expansion is far greater than steel/cast iron and as a result large movement holes are required... also many head gasket replacements require that the head bolts be replaced ...this is because of this aluminum expanding so much..

steel is much stonger than aluminum ....it also retains its shape better than aluminum which distorts easy....

the only reason aluminum is used is because of its weight and the ability to conduct heat from the engine..but the side effects are shorter engine life especially if the thermostat sticks just one time...by by engine..

since this is 2008 and most of us know that a cool engine will be a happy long lived one..

the aluminum that CAN be used from other sources , is much better than what the auto manufactures use..also gasket materials..

the tests of aluminum under high combustion temps will show that this metal is not very stong and will crack...and as a fact many have had this occur to them..with just running the vehicle slightly hot ...


on this flywheel bolt I would be very surprised to find that this spacer is required...especially from what we all know now..about this issue..

The reason aluminium heads warp when overheated is because aluminium has a lower melting point. The lower melting point brings a lower temperature where the material will creep. When an aluminium cylinder head overheats it creeps, flowing away slightly from the areas of high stress. This lessens clamping forces on the bolts and sealing faces, also means the bottom face won't be flat when it cools back down.

Many manufacturers are still battling with aluminium cylinder head designs, toyotas light diesels only sorted it out in the last 10 years.
Heads crack not because the material is brittle, but because they are subject to thermal fatigue.
Many aluminium based alloys are stronger than the most common grades of steel used.

everything you stated is absolutely correct...but the problem is quite frankly you and I will never know with all certainty what quality of the metals are used in our engines. with these auto companies going down fast they will put out the cheapest quality ...and then it's bad news for all of us...


quality is a thing of the past.. like I know in the days of quality ...overheating was a minor affair...not today...also GM and the others will never reveal the quality or spec's of the metals used....never...

everything you stated is absolutely correct...but the problem is quite frankly you and I will never know with all certainty what quality of the metals are used in our engines. with these auto companies going down fast they will put out the cheapest quality ...and then it's bad news for all of us...


quality is a thing of the past.. like I know in the days of quality ...overheating was a minor affair...not today...also GM and the others will never reveal the quality or spec's of the metals used....never...

I'm not convinced that quality is a thing of the past. 100,000 miles used to be a long life for a car, now if they don't make double that with just regular servicing then it's junk.
Companies are certainly always on the lookout to save every 10c, but they're also weary that a reputation as a dung maker will hurt them far more than an extra $1 per car.

While overheating now can spell the death of an engine, it doesn't seem to be as common as it used to be.
It all depends what business you're in as well. Mechanics don't often get sent cars in perfect running condition.:smokin:

I'm not convinced that quality is a thing of the past. 100,000 miles used to be a long life for a car, now if they don't make double that with just regular servicing then it's junk.
Companies are certainly always on the lookout to save every 10c, but they're also weary that a reputation as a dung maker will hurt them far more than an extra $1 per car.

While overheating now can spell the death of an engine, it doesn't seem to be as common as it used to be.
It all depends what business you're in as well. Mechanics don't often get sent cars in perfect running condition.:smokin:

I don't know how far back your going in time on this 100,000mi...
my first vehicle was 1967 I'm now on vehicle #4...the #3 vehicle a 1983 was a very well designed and tough ...original untouched transmission, engine , differential...cv joints ball joints ....17years 380,000mi...Only minor repairs like one starter motor one set of front rotors one tie rod one water pump...2 motor mounts ....all the other componets still worked ...fine... sold vehicle for 1700.oo...even the seats were far superior to the cheap ones I have now in my LT silverado...

most of the new vehicles use plastic and inferior fasteners ..these items can't stand up to the bad winter /roads of the rust belt regions...

after 4 years these newer vehicles are pretty beat..here..


also these brake rotors made today after 3-4years, they rot out from the inside out...rot holes in the middle of the rotor face ...this is something that has surface just over the past 5years...never seen that in the 1960-90 era..

most of the new vehicles use plastic and inferior fasteners ..these items can't stand up to the bad winter /roads of the rust belt regions...

after 4 years these newer vehicles are pretty beat..here..


also these brake rotors made today after 3-4years, they rot out from the inside out...rot holes in the middle of the rotor face ...this is something that has surface just over the past 5years...never seen that in the 1960-90 era..

The oldest vehicle I've got is 85, if you knew the english vehicles we had proir to that you'd know why.:grinyes:

Most of the vehicles here are japanese now. The japanese vehicles still have their problems and quirks, but owner denial can be very strong.

My biggest concern is propietory parts that are completely un-necessary. I've just paid Nissan $20 each for 8 flywheel bolts. They are M11 with 1mm thread pitch, the head on them is an E20 inverted torx which I had to modify a socket to fit.:crying: