3800 Series 2 upper intake questions

[GM Guy]

Hey all,

I have the dreaded #5 miss fire and coolant consumption on my Sister's 2000 Pontiac Bonneville with the 3800 Series 2 engine.

I was on Rockauto.com and was picking out parts, and was curious what was recommended fr gaskets?

The blue OE grade Delco is this number: 12573662

The black and red Delco is this number: 89017554 it also includes the TB gasket and the PCV gasket.


I will be getting the OE grade Delco upper intake.


Also, would I be fine just doing the upper intake, or would I be a fool to not do the lower one as well?

Someone said to do it right I need to do elbows and lower intake gasket, upper intake gasket, and upper intake.


Also, while this car is brought up, there is a sister machine, just one year newer (2001) with no 4th gear. How costly is that fix? Its rust and dent free for 600 bucks, that is why I ask.

Thanks!

 

[THEFERMANATOR]

Last one I did I did just the upper. I seen no reason to mess with the lower when it was only slightly distorted at the egr tube. I will also say be carefull torqing the upper intake. I tried torquing this one to spec, and it started cracking well before it got to spec. And yes, do the elbows with the metal ones. I think oem is still 0lastic, but they make cast aluminum ones in the help section at the parts store. And I have no idea on the no 4th. FWD isn't my thing.

 

[GM Guy]

So @THEFERMANATOR what would you suggest I go with on the gasket for the upper?

Thanks!

 

[THEFERMANATOR]

I used the black and red fel pro set iirc.

 

[GM Guy]

So I have never been into a 3800 series 2, and I am on the road currently so cant check, are the coolant elbows serviceable seperately then? As in the lower can stay in place?

What is the usual failure, plastic splits and pee's coolant all over?

 

[THEFERMANATOR]

Yes, they can be done seperately. GM used that infamous black plastic for the heater hose feed and return at the engine, and they fail over time.

And the more I think about it, the more I think I did the lower intake too. It's been awhile since I did one, so I just can't remember. I know I had to do the upper, the elbows, and a water pump on it, can't remember for certain if I did the lower or not.

 

[3500GMC]

The elbows are made in china, which for what they are isn't so bad.. The ones I used (help parts) had green orings that basically melted and failed within the first 4000 miles of use. Recommendation: Use regular old black rubber orings in place of the green ones.

 

[THEFERMANATOR]

The elbows are made in china, which for what they are isn't so bad.. The ones I used (help parts) had green orings that basically melted and failed within the first 4000 miles of use. Recommendation: Use regular old black rubber orings in place of the green ones.

I think I read about this and swapped them out as well. The elbows are cheap cast aluminum, but sure seemed alot better than the replacement nylon ones. I read on some of the forums that others had good luck with the help ones. I figure if you have to change them when you do your coolant, it's no big deal, but if you keep good coolant with good PH, then corrosion shouldn't be a big concern.