Anyone changed out a leaking intake gasket in their '00-05 Monte? If so was the job difficult?

The local Chevy dealer wants almost $800 for this job. I thought if I could gain some pointers from someone who's done this job I could save myself $500?

I was planning on purchasing an aftermarket motor manual. Look through it to see if changing the intake gasket was mentioned in there?

Any help would be appreciated. Thanks.

 

Upper or Lower?

 

Both?

I have no idea? The dealer just told me the intake was starting to leak when they checked the car out last fall. And I believe the issue may be getting worse?

 

I would find out which one it is. The upper intake is a piece of cake to change out (just look at any HV3 install), the lower intake is much more time consuming.

 

The LIM isn't much more work than the UIM. Just a few extra bolts and taking off the EGR.

 

So how do you tell which gasket needs replaced?

 

You will have to look at it but personally, I would replace the lower one because it usually goes out on 3800's. I haven't heard about too many problems with the upper intake gasket's going.

It takes a little time to do but if you buy a Haynes manual or something like that you should be able to do it sense you haven't done it before. Make sure you get the aluminum gaskets for the LIM. They're really good and usually people don't have any problems with them. They look like this:



Then you will also have to buy a coolant elbow because I have never heard of anyone doing the job without breaking it, lol.

 

I would change the UIM, you never heard of them going bad?? It's pretty common AFAIK, even mine was bad but luckily when I did my HV3 I was able to change it out... my front valve cover was shot too.

If you are doing the LIM, might as well do both.

x2 on the elbows. I have an extra set in my trunk just in case because they can sometimes be hard to find (I found mine at Pep-boys in the self-help section for like $4)

 

If you replace the lower intake gaskets, get the manifold checked for straightness. I am in the process of replacing mine. It was leaking oil really bad from both ends of the intake. Once I got it apart, I noticed that some one had already replaced the gaskets. I took the manifold to the machine shop, and they found that it was warped by .005. I had to have it milled back true.

Who ever did it last time didn't use or doesn't know how to use a fricken torque wrench, since the lower bolts were only hand tight. So, I don't know if that caused the intake be get warped or what. It would suck to replace the gaskets and then have it start leaking again due to a warped intake. Also, if you haven't replaced your plugs in a while, its a good time to do it, since its easier to get to them with it tore apart.

 

This will also help you when you put it back together. The following is the tighting sequence and torque specs for the lower and upper intakes.





Install the lower intake manifold bolts (1-12). Apply thread lock compound GM P/N 12345382 or equivalent to the two hidden bolts(numbers 5 & 7) and ensure they are installed.Tighten the lower intake manifold bolts in sequence to 15 N·m (11 lb ft).

1. Carefully place the upper intake manifold onto the lower intake manifold. Ensure that the alignment pins in the upper intake manifold align with the holes in the lower intake manifold.
2. Install the upper intake manifold.
3. Apply thread lock compound GM P/N 12345382 or equivalent, to the bolt threads before assembly.

Notice

Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

1. Install the upper intake manifold bolts (1-10).TightenTighten the upper intake manifold bolts in sequence to 10 N·m (89 lb in).