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Discussion Starter #1
So I was looking at the torque specs on this motor I'm putting back together ( stock ) and noticed for 96-97, it has specs that look an awful lot like the head bolt specs for those years. This concerns me because the head bolts were switched to TTY and are not reusable. Are the rod bolts one-time-use TTY as well?

If so, that really sucks if you want to use plasti-gauge to check bearing tolerances. Torque them down once to check, but then replace them to do the final install.

The fact I don't see them for sale on rockauto at all inclines me to believe they are reusable. That, and they look to be hard to remove from the rods. Can I reuse these? If not, how am I supposed to check bearing clearances without having to buy two sets?
 

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I consulted the 96 service manual. For connecting rod cap fitting they use a foot pound measurement followed by an additional 55 degrees. The manual makes no mention of having to replace the rod bolts.

You might want to try to find a 97 service manual to make sure GM didn't change the type of rod bolt and torque procedure. 96 manual @ following link.
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Discussion Starter #3 (Edited)
I consulted the 96 service manual. For connecting rod cap fitting they use a foot pound measurement followed by an additional 55 degrees. The manual makes no mention of having to replace the rod bolts.

You might want to try to find a 97 service manual to make sure GM didn't change the type of rod bolt and torque procedure. 96 manual @ following link.
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Don't reusable rods state to just torque to a food pound and done? Usually the lower foot pound followed by degrees indicates torque to yield.

One way to tell is to check that service manual to see if it tells you to replace the head bolts or just give the same instructions for torquing. Because we already know you have to replace those, if it doesn't say to then we'll know we can't go by the lack of instruction.
 

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Discussion Starter #4
I just checked the 96 service manual section for cylinder head replacement and it said nothing about using new bolts, but we know you're supposed to on tty head bolts. So the service manual is useless in answering my question.
 

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There are many newer cars that manufacture gives torque instructions to go to a certain inch or foot pound readings and then turn fastener additional degrees.

All bolts I've seen that are tty, the service manual tells the mechanic what they are. And the need to replace when part is taken apart. GM not saying anything about a fastener being torque to yeald, tells me fastener is of regular type.

When I was in the air force back in the 70's, it was common practice for aircraft repair manual to give a torque reading followed by additional turning of fasterner. Fasteners were not replaced unless they had a problem.
 

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Discussion Starter #6
All bolts I've seen that are tty, the service manual tells the mechanic what they are. And the need to replace when part is taken apart. GM not saying anything about a fastener being torque to yeald, tells me fastener is of regular type.
So the head bolts are reusable then also? Because I just looked that part up in the same service manual you linked to and it said nothing about using new bolts for the cylinder heads.
 

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96 service manual is just a starting place. You still need to find a 97 manual and look in it. All I can say for sure is 96 didn't use tty rod or head bolts. 97 may be a different story.
 

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96 service manual is just a starting place. You still need to find a 97 manual and look in it. All I can say for sure is 96 didn't use tty rod or head bolts. 97 may be a different story.
This is where I'm confused. You're saying 96 didn't use tty head bolts. Yet, in a different thread I asked about the specs given in the Hayne's manual and was told 1996 WAS the year they switched to TTY head bolts.

https://www.ls1lt1.com/forum/lt1-|-lt4-|-l99-engine-tech/128767-cylinder-head-bolt-torque-specs.html

The block and heads are the same, the difference in the procedure was because of the switch. Unless Shoebox was wrong?
 

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My main point in thinking that 96 used regular bolts was the fact that 96 service manual never said anything about changing the bolts when head or connecting rods were taken apart & put back together.
 
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