Manual says to replace Intake Manifold bolts. Why?

[crypkilla]

2003 Chevy Astro. 320,000 miles

I’m gonna replace the lower intake manifold gasket which means of course that I’ll be removing the lower intake manifold. The gasket set instructions say that replacement of the intake manifold bolts is recommended. It actually doesn’t say that in my AllData Reference Center manual.

Just curious why it’s recommended. Are they torque-to-yield like some head bolts? So should I drop the $18 for a set from Rock Auto instead a couple bucks at the local hardware store? Is the reason less important or something I can work around, and the aftermarket industry is just trying to sell me a new set of bolts? (Over $30 at Oreilly and Autozone).

Topic

[Stephen Bowen]

After all the nonsense I just went through with my intake manifold?

Replace the bolts. One of my bolts worked themselves loose and caused a nice leak into #4 cylinder of coolant. I wouldn’t hesitate to replace the bolts and run a tap down the block holes for the intake to clean out the threads. If that’s what the manual states and is recommended?

$14 bucks-$20 bucks can save having to do the job over again- Cheap insurance.

S-

[crypkilla]

good advice. I’ll be sure and clean the holes really well.

At 320k I won’t be taking any chances.

[Austin]

I would assume they are torque to yield. I’de follow the recommendation. If something happens, it’s a long way back in.

[EricTheCarGuy]

If they say to replace them in the service manual, I’d replace them. Somebody decided it would be a good idea and based on some of the comments it’s probably a good idea. Cheap insurance if you think about it.

[Gary]

I would just replace them. Better than the potential headache of not following the manuals recommendation.

[Author]

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