Broken Exhaust Manifold Bolt

04HDLong · November 2, 2011

Hen avenger, what grade of stainless hardware did you use was it grade 5 or 8?

Just sold my 01 2500 which had the same problem. The 04 2500 HD I just bought has the same problem, back bolts on both sides. The passenger side was easy. The driver's side required removing all the body bolts underneath the cab and the radiator support bolts along with the driver's side inner fenderwell. Release the slip yoke for the steering column and lift the body on the driver's side as high as it will allow without breaking anything. This height is needed to get the right angle air drill with shortened drill bits to clear the firewall and get a straight shot at that bolt. If you do not have the tools or ability to tackle this on your own, $300.00 from a dealer is not bad. Took me the better part of the day to do both sides and do it right. ARP makes studs that I will be using to tackle the 04 when I can get to it. Seems as though they have a higher tensile strength, from what I've been told, and should not break the way the bolts do. Good luck with your repair.

Big Windy Ext · November 4, 2011

$300 sounds like a good price,I had an 02 3/4 ton Suburban 6.0 that had broken bolts dealer quoted $750.00 but was done for free on a customer satisfaction repair. The body of my truck was lifted off also,at the dealer for 2 days . $300 sounds like a bargain if done right.

Joe138 · December 21, 2011

I was actually able to get my dealer to cover the whole job, new manifolds and all at 0 cost to me on my '03 that was 3 years out of warranty at the time. It took some phone calls to GM but they got it done. Allegedly they installed a better bolt the second time. I've got 3 missing bolt heads again. Obama closed my dealership so I don't think I'll get so lucky the second time.

dgkarr · March 6, 2012

My 2003 Silverado pickup truck has ben found to have a common and recurrent problem. Exhaust manifold bolts break, and on the driver side rear, they can be expensive to repair. A few miniutes of web searching on this topic produced a number of results and my conclusion is the issue is common. The online complaints also indicate that the success rate for the repair is not good, with many repaired vehicles having subsequent bolt failures. My vehicle is in an authorized Chevy service garage having the bolts replaced. The original estimate was for $486, if cylinder head did not need to be removed. The service technician broke a tap off in the rear most bolt location, left. I don't know if it happened before head removal or after. It became necessary to remove the cylinder head and was requoted at $1600. The head was sent to a local engine rebuilder whom I have known for 40 years. He says the problem is common also.

A call was made to GM 3-6-12. The response was that my truck was out of warranty and therefore they could be of no assistance in the mattrer. I am certainly aware of the warranty terms. My issue is with the scale of this engineering/manufacturing defect and the cost to the owners.

Has other owners had any luck in pressuring GM for help?

Riverjet502 · March 7, 2012

Just curious as to how many miles this takes to occur? People having this problem at @ the same mileage or is it a wide variance in miles driven?

pmax · March 12, 2012

I had three broken on my '01 HD. My mechanic replaced the exhaust manifolds for $200 labor per side. I supplied the parts. Manifolds were reasonable at around $200 for the pair. My guy told me he removed the fender liners for better access.

arwriter · March 13, 2012

My 2003 Silverado pickup truck has ben found to have a common and recurrent problem. Exhaust manifold bolts break, and on the driver side rear, they can be expensive to repair. A few miniutes of web searching on this topic produced a number of results and my conclusion is the issue is common. The online complaints also indicate that the success rate for the repair is not good, with many repaired vehicles having subsequent bolt failures. My vehicle is in an authorized Chevy service garage having the bolts replaced. The original estimate was for $486, if cylinder head did not need to be removed. The service technician broke a tap off in the rear most bolt location, left. I don't know if it happened before head removal or after. It became necessary to remove the cylinder head and was requoted at $1600. The head was sent to a local engine rebuilder whom I have known for 40 years. He says the problem is common also.

A call was made to GM 3-6-12. The response was that my truck was out of warranty and therefore they could be of no assistance in the mattrer. I am certainly aware of the warranty terms. My issue is with the scale of this engineering/manufacturing defect and the cost to the owners.

Has other owners had any luck in pressuring GM for help?

My '99 2500 has just over 88,000 miles on it and it has this same issue. I have yet to ask or press the dealer about it because it only leaks on start up and goes away shortly. Power and fuel mileage have not been affected.

Riverjet502 · March 13, 2012

My 04 has 32k on the clock. Sounds like a good preventive maintance project would be to change out these manifold bolts/studs before they give me grief? Sounds like the GM replacements bolts/studs are junk too.. Anyone found a good solution through the after market vendors?

redjewel2ss · March 13, 2012

i hope this crap has been fixed on the newer models last thing people with GMT900s need is a recurring problem that could've been fixed years ago!

March 19, 2012

My 04 has 32k on the clock. Sounds like a good preventive maintance project would be to change out these manifold bolts/studs before they give me grief? Sounds like the GM replacements bolts/studs are junk too.. Anyone found a good solution through the after market vendors?

Proactive action is a good idea, if you can get them out without breaking. Of course it is just a matter of time until they break anyway. On my 2002 6.0 it was a difficult job. Four broken bolts, but I was lucky, they all broke off leaving some of the bolt sticking out so I did not have to drill. One still came out very difficult. If they break off flush, welding a nut on is worth a try before pulling the head. Unfortunately, the dip stick tube was rusted where it passes through the exhaust manifold and it broke off as soon as it was disturbed. $29 for a new tube was not so bad, but do you think the tube would come out of the block? Hours were squandered away trying to get it out. The end extends into the block. Some crud built up on the end of the tube and it wedged the tube and o-ring making it nearly impossible to get out. The EGR tube came off only after torching the bolts. The manifolds were warped and the gasket surface was deteriorated. Dorman makes nice replacements with lifetime warranty which I got for $89 apiece. GM manifolds list for $250 apiece. I used the upgraded bolts from GM. After two years the heat shields on the Dorman manifolds were a swelled up layer of rust and would crumble at the slightest touch. The casting of the manifolds looked great. So the Dorman's are great for a short term repair. I recently traded the 02 in because I was tired of seeing it transform into a rust bomb. Brake lines, frame, rocker panels, and door bottom seams were all of a sudden being overcome with rust. The 2011 has improvements, but I miss the 02.

Riverjet502 · March 26, 2012

Anyone know what size bolt these are and how long? I believe they are metric?

youcantkeepup! · March 26, 2012

i hope this crap has been fixed on the newer models last thing people with GMT900s need is a recurring problem that could've been fixed years ago!

it still happens to the 900's it happened to minee and i got both manifolds gaskets all bolts and heat shields covered under the 5yr/100mile powertrain warranty

rkr · March 28, 2012

I believe they are M8 bolts. What do you think, would normal grade 8 bolts be a good replacement?

Edit: Or would it be better to use DIN912 type hexagon socket head cap screws, they have smaller head diameter so they should fit better in there?

Riverjet502 · March 28, 2012

I think they are a M8-1.25??? Sound right? Has anyone tried a 9.8 or a 10.9? Any thoughts on this?

xor · April 7, 2012

Driver and passenger side rear bolts broke on my 2001 6.0L. Got lucky and had enough bolt exposed to painstakingly extract with vise grips. One of the new bolts kept loosening due the slightly warped manifold flexing as it heated/cooled, had to tighten it every 2-3 weeks. Solved it with Nord-Lock washers, 7 months now without a loose bolt.

Got parts from mcmaster.com.

grade 10.9 bolts part number 90854A170

Nord-Lock (wedge lock) washers part number 91812A230