2004 lq4 mid year engine head bolts.
Thread Starter
Staging Lane
Joined: Apr 2023
Posts: 57
Likes: 4
2004 lq4 mid year engine head bolts. So I'm mid engine rebuild. And I told the shop kid to throw my bolts away before looking to see if I had the same or seperate length bolts lol.
Its a mid year 2004 lq4 from an express.
I'm assuming the bolt length difference is in the block not the heads?
One bolt kit does 1 side. 1 has 2 shorter bolts and 8 long
The other has 10 long.
Which bolt holes are the short ones if it is in the block?
Its a mid year 2004 lq4 from an express.
I'm assuming the bolt length difference is in the block not the heads?
One bolt kit does 1 side. 1 has 2 shorter bolts and 8 long
The other has 10 long.
Which bolt holes are the short ones if it is in the block?
So I'm mid engine rebuild. And I told the shop kid to throw my bolts away before looking to see if I had the same or seperate length bolts lol.
Its a mid year 2004 lq4 from an express.
I'm assuming the bolt length difference is in the block not the heads?
One bolt kit does 1 side. 1 has 2 shorter bolts and 8 long
The other has 10 long.
Which bolt holes are the short ones if it is in the block?
Its a mid year 2004 lq4 from an express.
I'm assuming the bolt length difference is in the block not the heads?
One bolt kit does 1 side. 1 has 2 shorter bolts and 8 long
The other has 10 long.
Which bolt holes are the short ones if it is in the block?
Thread Starter
Staging Lane
Joined: Apr 2023
Posts: 57
Likes: 4
So the top outer are shorter. Any idea how much?
I guess it doesn't matter. Any shorter means shorter means older bolt kit.
My apologies sir…I ASSumed you had already bought the early kit. ARP’s bolt kit would be 134-3609 for the early block. Mid 2005ish GM started the changeover to the all long bolt blocks, which would be…in ARP…134-3610. Just posting part numbers for comparison.
Thread Starter
Staging Lane
Joined: Apr 2023
Posts: 57
Likes: 4
03shows the kit with 2 short 8 long.
05 shows 10 long.
04 express vans show both kits available.
Measuring the blocks bolt holes I have determined mine are all the same length. So 2nd kit.
TECH Senior Member
Joined: Jun 2016
Posts: 22,303
Likes: 3,619
From: Central Cal.
I thought the later bolts were all SHORT.
Early are (2) M11 x 2 x 100, (8) M11 x 2 x 155
Late are (10) M11 x 2 x 100
As per Summit data sheets
Early are (2) M11 x 2 x 100, (8) M11 x 2 x 155
Late are (10) M11 x 2 x 100
As per Summit data sheets
Last edited by G Atsma; Jan 11, 2024 at 02:24 PM.
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Thread Starter
Staging Lane
Joined: Apr 2023
Posts: 57
Likes: 4
I switched them.
So a question then.
Wouldn't the shorter ones work on all years? If there's no change with the head. Then it shouldn't matter?
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Verdad Gallardo TECH Senior Member
Joined: Jun 2016
Posts: 22,303
Likes: 3,619
From: Central Cal.
It’s very hit-or-miss. I’ve seen some 05’s with both lengths, both 6 liter blocks. Now ToastedPirate is saying he saw books with ‘04 model year being the changeover year. GM put the leftover unequal length block engines in whatever came down the line in several assembly plants, until they ran out. No telling what you find out there really.
Thread Starter
Staging Lane
Joined: Apr 2023
Posts: 57
Likes: 4
The bolts don't bottom out in the block even with stretch fit, so the number of threads below the bolt shouldn't matter. If it's the newer block or the older design the short bolt still threads in the same number of threads.
Regardless. Mine are all the same length so I need the 2nd design bolts.
Both bolt sets list for the 2004.
