My manual says to tighten them to 55 ft-lbs, then again to 55 ft-lbs, then 90 degrees more -- like the head bolts.

Does this mean I need new ones once I take them out?

I used the search, but came up empty.

Mitch...if it were me, I would invest in ARP main studs. Reduce the chances of cracking the webbing.

Mitch...if it were me, I would invest in ARP main studs. Reduce the chances of cracking the webbing.good idea

X3

But to answer your question in regards to the bolts, I was told by a GM service tech that nowhere in any of their tech manuals does it say to replace maincap bolts.

The torque spec sure does raise some questions about whether or not the bolts are being torqued up to their yield point or not.

The ARP hardware I used on mine is as follows:

Inner (long) stud ARP # AU4.600 KB
Outer (short) stud ARP # AU3.965 KB
12mm x 1.25 12pt nut(10 pack) ARP # 300-8337
12mm ID x .750" OD washer(10 pack) ARP # 200-8536

Cost was around $240-ish

I would suggest that you replace them.

From your other thread(http://www.dieselplace.com/forum/showthread.php?t=271117)
you mentioned that they were torqued a LOT tighter than the factory specs. If they were over-tightened, that might lead to your excessive wear on the main and rod bearings. Also, it may have over-stressed the bolts, which could lead to failure sometime down the road.

You're going to the trouble of rebuilding the engine. Why cut a few corners now? If you have to cut corners, do it somewhere else where its easy to upgrade later. (like the PMD, fer instance)

Cheers.

I would suggest that you replace them.

From your other thread(http://www.dieselplace.com/forum/showthread.php?t=271117)
you mentioned that they were torqued a LOT tighter than the factory specs. If they were over-tightened, that might lead to your excessive wear on the main and rod bearings. Also, it may have over-stressed the bolts, which could lead to failure sometime down the road.

You're going to the trouble of rebuilding the engine. Why cut a few corners now? If you have to cut corners, do it somewhere else where its easy to upgrade later. (like the PMD, fer instance)

Cheers.

Well said. ...Main reason I asked is because I wanted to plastigage the mains. But when I took the caps off, I could see they were hosed, so I didn't bother.

Studs it is, then! ...and the PMD is going either in the bumper snout or behind the grill. ...already have the heat sink.